blood-borne pathogens, tuberculosis update, and infection control timothy r. cassity, ph. d....

Blood-borne Pathogens, Blood-borne Pathogens, Tuberculosis Update,Tuberculosis Update,and Infection Controland Infection Control

Timothy R. Cassity, Ph. D.Timothy R. Cassity, Ph. D.

MicrobiologistMicrobiologist

October 9, 2007October 9, 2007

ObjectivesObjectives

Not to bore you – or send you to Not to bore you – or send you to La-La LandLa-La Land


Not to bore you – avoid La-La LandNot to bore you – avoid La-La LandFulfill OSHA requirementsFulfill OSHA requirements


Not to bore you – avoid La-La LandNot to bore you – avoid La-La LandFulfill OSHA requirementsFulfill OSHA requirementsEarn some CEUsEarn some CEUs


Not to bore you – avoid La-La LandNot to bore you – avoid La-La LandFulfill OSHA requirementsFulfill OSHA requirementsEarn some CEUsEarn some CEUsLearn – or be reminded of Learn – or be reminded of

information that is hopefully information that is hopefully usefuluseful

ReferencesReferences

Most of the information for this Most of the information for this presentation was taken from the CDC presentation was taken from the CDC website at website at http://www.cdc.gov/http://www.cdc.gov/ and and included references from included references from Morbidity Morbidity and Mortality Weeklyand Mortality Weekly report and report and Emerging Infectious DiseasesEmerging Infectious Diseases

Human Immunodeficiency Virus Human Immunodeficiency Virus (HIV)(HIV)

HIV - Description of the agentHIV - Description of the agent


This is the virus This is the virus that causes AIDSthat causes AIDS


This is the virus This is the virus that causes AIDS that causes AIDS

HIV finds and HIV finds and destroys CD4 T destroys CD4 T cells and cells and destroys the destroys the immune system.immune system.


This is the virus that This is the virus that causes AIDS causes AIDS

HIV finds and destroys HIV finds and destroys CD4 T cells and CD4 T cells and destroys the immune destroys the immune system. system.

HIV is a retrovirus.HIV is a retrovirus. These are RNA viruses, These are RNA viruses,

that in order to that in order to replicate must make a replicate must make a DNA copy of their RNA.DNA copy of their RNA.


HIV and other retroviruses, once HIV and other retroviruses, once inside a cell, use reverse inside a cell, use reverse transcriptase to convert their transcriptase to convert their RNA into DNA, which can be RNA into DNA, which can be incorporated into the host cell's incorporated into the host cell's genes.genes.

HIV History – Where did it come HIV History – Where did it come from?from?

HIV - HistoryHIV - History

Scientists Scientists identified a type identified a type of chimpanzee in of chimpanzee in West Africa as the West Africa as the source of HIV source of HIV infection in infection in humans.humans.


AIDS was first identified in the AIDS was first identified in the United States in 1981 after a United States in 1981 after a number of homosexual men were number of homosexual men were diagnosed with Kaposi’s diagnosed with Kaposi’s sarcoma.sarcoma.


Although HIV was first identified Although HIV was first identified in 1983, studies of previously in 1983, studies of previously stored blood samples indicate stored blood samples indicate that the virus entered the U.S. that the virus entered the U.S. population sometime in the late population sometime in the late 1970s1970s


During the early 1980s, as many During the early 1980s, as many as 150,000 people became as 150,000 people became infected with HIV each year.infected with HIV each year.


By the early 1990s, this rate had By the early 1990s, this rate had dropped to about 40,000 each dropped to about 40,000 each year. year.


AIDS cases began to fall AIDS cases began to fall dramatically in 1996, when new dramatically in 1996, when new drugs became available.drugs became available.


CDC estimates that about 1 CDC estimates that about 1 million people in the United million people in the United States are living with HIV or States are living with HIV or AIDSAIDS


CDC estimates that about 1 million CDC estimates that about 1 million people in the United States are living people in the United States are living with HIV or AIDSwith HIV or AIDSAbout one quarter of these people About one quarter of these people

do not know that they are infecteddo not know that they are infected

Easy questions?Easy questions?

HIV – Scope of InfectionHIV – Scope of Infection

Worldwide, an estimated 38 Worldwide, an estimated 38 million people were living with million people were living with HIV/AIDS as of December 2003.HIV/AIDS as of December 2003.


Through 2003, cumulative AIDS-Through 2003, cumulative AIDS-associated deaths worldwide associated deaths worldwide numbered more than 20 million.numbered more than 20 million.


Globally, approximately 5 million Globally, approximately 5 million new HIV infections and new HIV infections and approximately 3 million AIDS-approximately 3 million AIDS-related deaths, including an related deaths, including an estimated 490,000 children estimated 490,000 children under 15 years old, occurred in under 15 years old, occurred in the year 2003 alone.the year 2003 alone.

HIV - PathogenesisHIV - Pathogenesis

Untreated HIV disease is Untreated HIV disease is characterized by a gradual characterized by a gradual deterioration of immune deterioration of immune function.function.


Untreated HIV disease is Untreated HIV disease is characterized by a gradual characterized by a gradual deterioration of immune function. deterioration of immune function.

Most scientists think that HIV Most scientists think that HIV causes AIDS by directly inducing causes AIDS by directly inducing the death of CD4+ T cells or the death of CD4+ T cells or interfering with their normal interfering with their normal function function


Infection typically begins when Infection typically begins when an HIV particle, which contains an HIV particle, which contains two copies of the HIV RNA, two copies of the HIV RNA, encounters a CD4+ cell with encounters a CD4+ cell with appropriate receptors.appropriate receptors.


The envelope of the virus and The envelope of the virus and the cell membrane then fuse, the cell membrane then fuse, leading to entry of the virus into leading to entry of the virus into the cell. the cell.


Cell-to-cell spread of HIV also Cell-to-cell spread of HIV also can occur through the CD4-can occur through the CD4-mediated fusion of an infected mediated fusion of an infected cell with an uninfected cell.cell with an uninfected cell.


Once it enters the body, HIV Once it enters the body, HIV infects a large number of CD4+ infects a large number of CD4+ cells and replicates rapidly.cells and replicates rapidly.


Once it enters the body, HIV infects a Once it enters the body, HIV infects a large number of CD4+ cells and large number of CD4+ cells and replicates rapidly. replicates rapidly. During this acute or primary phase During this acute or primary phase

of infection, the blood contains of infection, the blood contains many viral particles that spread many viral particles that spread throughout the body, seeding throughout the body, seeding various organs, particularly the various organs, particularly the lymph system.lymph system.


Two to 4 weeks after exposure to Two to 4 weeks after exposure to the virus, up to 70 percent of the virus, up to 70 percent of HIV-infected people suffer flu-HIV-infected people suffer flu-like symptoms related to the like symptoms related to the acute infection.acute infection.


Their immune system fights back Their immune system fights back with killer T cells (CD8+ T cells) with killer T cells (CD8+ T cells) and B-cell-produced antibodies.and B-cell-produced antibodies.


Their immune system fights back Their immune system fights back with killer T cells (CD8+ T cells) and with killer T cells (CD8+ T cells) and B-cell-produced antibodies. B-cell-produced antibodies.

These dramatically reduce HIV These dramatically reduce HIV levels.levels.


Some HIV invariably escapes the Some HIV invariably escapes the CD8 cells and antibodies and CD8 cells and antibodies and persists.persists.


Some HIV invariably escapes the CD8 Some HIV invariably escapes the CD8 cells and antibodies and persists.cells and antibodies and persists.

This is due in large part to the This is due in large part to the high rate of mutations that occur high rate of mutations that occur during the process of HIV during the process of HIV replication.replication.


Some HIV invariably escapes the CD8 Some HIV invariably escapes the CD8 cells and antibodies and persists.cells and antibodies and persists.

The virus may hide within the The virus may hide within the chromosomes of an infected cell chromosomes of an infected cell and be shielded from and be shielded from surveillance by the immune surveillance by the immune system.system.


The median time from infection The median time from infection with HIV to the development of with HIV to the development of AIDS-related symptoms has been AIDS-related symptoms has been approximately 10 years in the approximately 10 years in the absence of antiretroviral absence of antiretroviral therapy.therapy.


Numerous studies show that Numerous studies show that people with high levels of HIV in people with high levels of HIV in their bloodstream are more their bloodstream are more likely to develop AIDS-related likely to develop AIDS-related symptoms or die than those with symptoms or die than those with lower levels of virus.lower levels of virus.

Preguntas?Preguntas?

HIV - TransmissionHIV - Transmission

HIV is a fragile virus.HIV is a fragile virus. It cannot live for very long outside the It cannot live for very long outside the

body.body.


HIV is a fragile virus.HIV is a fragile virus. Drying of HIV-infected human blood or Drying of HIV-infected human blood or

other body fluids reduces the theoretical other body fluids reduces the theoretical risk of environmental transmission to risk of environmental transmission to essentially zero. essentially zero.


You cannot get HIV by:You cannot get HIV by:Shaking handsShaking hands


You cannot get HIV by:You cannot get HIV by:Shaking handsShaking handsHuggingHugging


You cannot get HIV by:You cannot get HIV by:Shaking handsShaking handsHuggingHuggingCasual kissing (more later)Casual kissing (more later)


You cannot get HIV from:You cannot get HIV from:Toilet seats, doorknobs, or drinking Toilet seats, doorknobs, or drinking

fountainsfountains



fountainsfountainsDishes, glasses, or foodDishes, glasses, or food



fountainsfountainsDishes, glasses, or foodDishes, glasses, or foodPets or mosquitoesPets or mosquitoes


There is no known risk of HIV There is no known risk of HIV transmission to co-workers, transmission to co-workers, clients, or consumers from food-clients, or consumers from food-service establishmentsservice establishments


HIV has HIV has NOTNOT been recovered been recovered from the sweat of HIV-infected from the sweat of HIV-infected persons.persons.


HIV has HIV has NOTNOT been recovered from been recovered from the sweat of HIV-infected persons.the sweat of HIV-infected persons.

Contact with saliva, tears, or Contact with saliva, tears, or sweat has never been shown to sweat has never been shown to result in transmission of HIV.result in transmission of HIV.

HIV - TransmissionHIV - TransmissionKissingKissing

Casual contact through closed-mouth Casual contact through closed-mouth kissing is not a risk for transmission of kissing is not a risk for transmission of HIV.HIV.


Because of the potential for contact with Because of the potential for contact with blood during "French" or open-mouth blood during "French" or open-mouth kissing, CDC recommends against kissing, CDC recommends against engaging in this activity with a person engaging in this activity with a person known to be infected with HIV.known to be infected with HIV.


However, the risk of acquiring HIV However, the risk of acquiring HIV during open-mouth kissing is believed to during open-mouth kissing is believed to be very low. be very low.

HIV - TransmissionHIV - TransmissionBitingBiting

There have been other reports in the There have been other reports in the medical literature in which HIV appeared medical literature in which HIV appeared to have been transmitted by a bite.to have been transmitted by a bite.


There have been other reports in the There have been other reports in the medical literature in which HIV appeared medical literature in which HIV appeared to have been transmitted by a bite.to have been transmitted by a bite.Severe trauma with extensive tissue tearing Severe trauma with extensive tissue tearing

and damage and presence of blood were and damage and presence of blood were reported in each of these instances.reported in each of these instances.


There are numerous reports of bites that There are numerous reports of bites that did did NOTNOT result in HIV infection. result in HIV infection.


HIV is primarily found in the HIV is primarily found in the blood, semen, or vaginal fluid of blood, semen, or vaginal fluid of an infected person.an infected person.


HIV is transmitted in 3 main HIV is transmitted in 3 main ways:ways:Having sex (anal, vaginal, or oral) with Having sex (anal, vaginal, or oral) with

someone infected with HIV.someone infected with HIV.



someone infected with HIV.someone infected with HIV.Sharing needles and syringes with Sharing needles and syringes with

someone infected with HIV.someone infected with HIV.



someone infected with HIV.someone infected with HIV.Sharing needles and syringes with Sharing needles and syringes with

someone infected with HIV.someone infected with HIV.Being exposed (fetus or infant) to HIV Being exposed (fetus or infant) to HIV

before or during birth or through breast before or during birth or through breast feeding feeding

HIV – Transmission in Health HIV – Transmission in Health CareCare

Blood is the primary body fluid of Blood is the primary body fluid of concern.concern.


Cerebrospinal fluid, synovial Cerebrospinal fluid, synovial fluid, pleural fluid, peritoneal fluid, pleural fluid, peritoneal fluid, pericardial fluid, and fluid, pericardial fluid, and amniotic fluid are also amniotic fluid are also considered potentially considered potentially infectious.infectious.


Feces, nasal secretions, saliva, Feces, nasal secretions, saliva, sputum, sweat, tears, urine, and sputum, sweat, tears, urine, and vomitus are not considered vomitus are not considered potentially infectious unless they potentially infectious unless they are visibly bloodyare visibly bloody


Health-care exposures occur Health-care exposures occur through:through:NeedlesticksNeedlesticks


Health-care exposures occur Health-care exposures occur through:through:NeedlesticksNeedlesticksCuts from other sharp instruments Cuts from other sharp instruments

contaminated with an infected patient's contaminated with an infected patient's bloodblood


Health-care exposures occur Health-care exposures occur through:through:NeedlesticksNeedlesticksCuts from other sharp instruments Cuts from other sharp instruments

contaminated with an infected patient's contaminated with an infected patient's bloodblood

Contact of the eye, nose, mouth, or skin Contact of the eye, nose, mouth, or skin with a patient's blood. with a patient's blood.


Most exposures do not result in Most exposures do not result in infection.infection.


Transmission of HIV to patients Transmission of HIV to patients while in healthcare settings is while in healthcare settings is rare.rare.


The average risk for HIV The average risk for HIV transmission after a transmission after a percutaneous exposure to HIV-percutaneous exposure to HIV-infected blood has been infected blood has been estimated to be approximately estimated to be approximately 0.3%.0.3%.


The average risk for HIV transmission The average risk for HIV transmission after a percutaneous exposure to after a percutaneous exposure to HIV-infected blood has been HIV-infected blood has been estimated to be approximately 0.3%.estimated to be approximately 0.3%.

The average risk for HIV The average risk for HIV transmission after a mucous transmission after a mucous membrane exposure, membrane exposure, approximately 0.09%.approximately 0.09%.


Increased risk for HIV infection Increased risk for HIV infection was associated with exposure to was associated with exposure to a larger quantity of blood from a larger quantity of blood from the source person.the source person.


The risk also was increased for The risk also was increased for exposure to blood from source exposure to blood from source persons with terminal illness, persons with terminal illness, possibly reflecting either the possibly reflecting either the higher titer of HIV in blood late higher titer of HIV in blood late in the course of acquired in the course of acquired immunodeficiency syndrome immunodeficiency syndrome (AIDS).(AIDS).

Television Timeout?Television Timeout?

Diagnostic Testing and HIVDiagnostic Testing and HIV

HIV – Principles of DiagnosisHIV – Principles of Diagnosis

You cannot rely on symptoms You cannot rely on symptoms alone because many people who alone because many people who are infected with HIV do not are infected with HIV do not have symptoms for many years.have symptoms for many years.


The only way to know whether The only way to know whether you are infected is to be tested you are infected is to be tested for HIV.for HIV.


The only way to know whether The only way to know whether you are infected is to be tested you are infected is to be tested for HIV.for HIV.Once HIV enters the body, the body Once HIV enters the body, the body

starts to produce antibodies starts to produce antibodies

HIV – DiagnosisHIV – Diagnosis

Start with a screenStart with a screenHIV 1/2 combined assayHIV 1/2 combined assaySensitive but not very specific.Sensitive but not very specific.


If screen is positive, a If screen is positive, a confirmatory test must be confirmatory test must be performedperformedWestern blotWestern blotIndirect immunofluorescence Indirect immunofluorescence ImmunblotImmunblot


HIV nucleic acid (RNA) detectionHIV nucleic acid (RNA) detection Reverse transcriptase DNA polymerase Reverse transcriptase DNA polymerase

chain reaction [RT-PCR] chain reaction [RT-PCR] Primary use is not diagnostic, but to Primary use is not diagnostic, but to

monitor HIV load in a known positive monitor HIV load in a known positive patient.patient.

Useful for determining treatment Useful for determining treatment regimen and clinical course.regimen and clinical course.

HIV - PreventionHIV - Prevention

A=AbstinenceA=Abstinence


A=AbstinenceA=Abstinence

B=Be FaithfulB=Be Faithful


A=AbstinenceA=AbstinenceB=Be FaithfulB=Be Faithful

C=CondomsC=Condoms


Instruments that are intended to Instruments that are intended to penetrate the skin (such as penetrate the skin (such as tattooing and acupuncture tattooing and acupuncture needles, ear piercing devices) needles, ear piercing devices) should be used once and should be used once and disposed of or thoroughly disposed of or thoroughly cleaned and sterilized.cleaned and sterilized.


Instruments that are intended to Instruments that are intended to penetrate the skin (such as tattooing penetrate the skin (such as tattooing and acupuncture needles, ear piercing and acupuncture needles, ear piercing devices) should be used once and devices) should be used once and disposed of or thoroughly cleaned and disposed of or thoroughly cleaned and sterilized. sterilized. CDC knows of no instances of HIV CDC knows of no instances of HIV

transmission through tattooing or body transmission through tattooing or body piercing, although hepatitis B virus has been piercing, although hepatitis B virus has been transmitted during some of these practices.transmitted during some of these practices.


Instruments not intended to Instruments not intended to penetrate the skin but which penetrate the skin but which may become contaminated with may become contaminated with blood (for example, razors) blood (for example, razors) should be used for only one should be used for only one client and disposed of or client and disposed of or thoroughly cleaned and thoroughly cleaned and disinfected after each use.disinfected after each use.

HIV - VaccineHIV - Vaccine

Many have been devised and Many have been devised and tested.tested.


Many have been devised and tested.Many have been devised and tested.It is difficult to prepare a vaccine It is difficult to prepare a vaccine

and test it adequately on human and test it adequately on human subjects.subjects.


Many have been devised and tested.Many have been devised and tested. It is difficult to prepare a vaccine and It is difficult to prepare a vaccine and

test it adequately on human test it adequately on human subjects.subjects.

None have been effective to None have been effective to date.date.


Many have been devised and tested.Many have been devised and tested. It is difficult to prepare a vaccine and It is difficult to prepare a vaccine and

test it adequately on human test it adequately on human subjects.subjects.

None have been effective to date.None have been effective to date.There are no promising There are no promising

prospects for a vaccine on the prospects for a vaccine on the horizon.horizon.

Post-Exposure TestingPost-Exposure Testing

Test source if possibleTest source if possibleIf source is negative, PEP not a big issueIf source is negative, PEP not a big issue


HIV testing should be performed HIV testing should be performed on the employee immediately on the employee immediately after exposure.after exposure.


HIV testing should be performed HIV testing should be performed on the employee immediately on the employee immediately after exposure.after exposure.If baseline test is negative, test again at If baseline test is negative, test again at

3 months.3 months.


HIV testing should be performed on HIV testing should be performed on the employee immediately after the employee immediately after exposure.exposure.If 3 month test is negative, test again at If 3 month test is negative, test again at

6 months.6 months.


HIV testing should be performed HIV testing should be performed on the employee immediately on the employee immediately after exposure.after exposure.If 6 month test is negative, test again at If 6 month test is negative, test again at

1 year.1 year.

HIV – Post-Exposure Prophylaxis HIV – Post-Exposure Prophylaxis (PEP)(PEP)

If PEP is going to be If PEP is going to be administered, it should be administered, it should be initiated as soon as possible, initiated as soon as possible, preferably within hours of preferably within hours of exposure.exposure.


Persons receiving PEP should Persons receiving PEP should complete a full 4-week regimen.complete a full 4-week regimen.


Side effects have been reported Side effects have been reported frequently by persons taking frequently by persons taking antiretroviral agents as PEP.antiretroviral agents as PEP.


Because of the complexity of Because of the complexity of selection of HIV PEP regimens, selection of HIV PEP regimens, consultation with persons having consultation with persons having expertise in antiretroviral therapy expertise in antiretroviral therapy and HIV transmission is strongly and HIV transmission is strongly recommended.recommended.

PEPline at PEPline at http://http://www.ucsf.edu/hivcntr/Hotlines/PEPlinwww.ucsf.edu/hivcntr/Hotlines/PEPlinee; telephone 888-448-4911.; telephone 888-448-4911.


If PEP is offered and taken and If PEP is offered and taken and the source is later determined to the source is later determined to be HIV-negative, PEP should be be HIV-negative, PEP should be discontinued.discontinued.


Health care workers with Health care workers with occupational exposure to HIV occupational exposure to HIV should receive follow-up should receive follow-up counseling, post-exposure counseling, post-exposure testing, and medical evaluation testing, and medical evaluation regardless of whether they regardless of whether they receive PEP.receive PEP.


If PEP is used, the HCW should If PEP is used, the HCW should be monitored for drug toxicity by be monitored for drug toxicity by testing at baseline and again 2 testing at baseline and again 2 weeks after starting PEP.weeks after starting PEP.


If PEP is used, the HCW should If PEP is used, the HCW should be monitored for drug toxicity by be monitored for drug toxicity by testing at baseline and again 2 testing at baseline and again 2 weeks after starting PEP.weeks after starting PEP. Minimally, laboratory monitoring for Minimally, laboratory monitoring for

toxicity should include a CBC and renal toxicity should include a CBC and renal and hepatic function tests. and hepatic function tests.

HIV - TreatmentHIV - Treatment

Potent combinations of three or more Potent combinations of three or more anti-HIV drugs known as highly active anti-HIV drugs known as highly active antiretroviral therapy, or HAART, can antiretroviral therapy, or HAART, can reduce a person's viral load to very reduce a person's viral load to very low levels and in many cases delay low levels and in many cases delay the progression of HIV disease for the progression of HIV disease for prolonged periods. prolonged periods.


Before the introduction of HAART Before the introduction of HAART therapy, 85 percent of patients therapy, 85 percent of patients survived an average of 3 years survived an average of 3 years following AIDS diagnosis.following AIDS diagnosis.


Antiretroviral regimens have Antiretroviral regimens have delayed the clinical onset of delayed the clinical onset of AIDS and prolonged the lives of AIDS and prolonged the lives of individuals that have AIDS.individuals that have AIDS.


Antiretroviral regimens, Antiretroviral regimens, however, have yet to completely however, have yet to completely and permanently suppress the and permanently suppress the virus in HIV-infected people.virus in HIV-infected people.

Laws and EthicsLaws and Ethics

HIV – Legal IssuesHIV – Legal Issues

Source: Source: Adapted from the American Bar Adapted from the American Bar Association’s “Model HIV/AIDS Confidentiality Association’s “Model HIV/AIDS Confidentiality Policy.”Policy.”

Confidentiality must be strictly Confidentiality must be strictly maintained – this means maintained – this means anything that could associate a anything that could associate a person with HIV or AIDS or any person with HIV or AIDS or any other related disease must be other related disease must be kept confidential.kept confidential.



Confidentiality must be strictly maintained – this Confidentiality must be strictly maintained – this means anything that could associate a person means anything that could associate a person with HIV or AIDS or any other related disease with HIV or AIDS or any other related disease must be kept confidnetial.must be kept confidnetial.

This may require the use of This may require the use of aliases anonymous testing.aliases anonymous testing.



Confidentiality must be strictly maintained – this Confidentiality must be strictly maintained – this means anything that could associate a person means anything that could associate a person with HIV or AIDS or any other related disease with HIV or AIDS or any other related disease must be kept confidnetial.must be kept confidnetial.

This may require the use of aliases anonymous This may require the use of aliases anonymous testing.testing.

Records must be stored securely – both Records must be stored securely – both paper and electronicpaper and electronic


For research – aggregate, not For research – aggregate, not individual data, must be used.individual data, must be used.


Because it can be easy to Because it can be easy to inadvertently identify people inadvertently identify people when small numbers of cases are when small numbers of cases are broken down by age, broken down by age, race/ethnicity, gender, or other race/ethnicity, gender, or other factors, most state HIV/AIDS factors, most state HIV/AIDS surveillance programs have a surveillance programs have a restriction policy on small restriction policy on small sample size.sample size.

Hepatitis B VirusHepatitis B Virus

Hepatitis B - Description of the Hepatitis B - Description of the agentagent

Hepatitis B virus Hepatitis B virus (HBV), can cause (HBV), can cause lifelong infection, lifelong infection, cirrhosis (scarring) of cirrhosis (scarring) of the liver, liver cancer, the liver, liver cancer, liver failure, and liver failure, and death. death.


Humans are the only Humans are the only known host for HBV.known host for HBV.


Virions consist of an outer lipid Virions consist of an outer lipid envelope and an icasohedral envelope and an icasohedral nucleocapsid core composed of nucleocapsid core composed of protein.protein.


The nucleocapsid encloses the viral The nucleocapsid encloses the viral DNA and a DNA polymerase that has DNA and a DNA polymerase that has reverse transcriptase activity.reverse transcriptase activity.


The outer envelope The outer envelope contains embedded contains embedded proteins which are proteins which are involved in viral involved in viral binding.binding.


HBV is relatively HBV is relatively resilient and, in some resilient and, in some instances, has been instances, has been shown to remain shown to remain infectious on infectious on environmental surfaces environmental surfaces for more than 7 days at for more than 7 days at room temperature.room temperature.

Hepatitis B - HistoryHepatitis B - History

Originally called serum hepatitis.Originally called serum hepatitis.


The first recorded cases The first recorded cases hepatitis B are thought to be hepatitis B are thought to be those that followed the those that followed the administration of smallpox administration of smallpox vaccine containing human lymph vaccine containing human lymph to shipyard workers in Germany to shipyard workers in Germany in l883.in l883.


The role of blood as a vehicle for The role of blood as a vehicle for virus transmission was further virus transmission was further emphasized in 1943.emphasized in 1943.


Australia antigen, later called Australia antigen, later called hepatitis B surface antigen hepatitis B surface antigen (HBsAg), was first described in (HBsAg), was first described in 1965, and the Dane particle 1965, and the Dane particle (complete hepatitis B virion) was (complete hepatitis B virion) was identified in 1970.identified in 1970.

Hepatitis B - PrevalenceHepatitis B - Prevalence

In 1987, the CDC estimated the In 1987, the CDC estimated the total number of HBV infections in total number of HBV infections in the United States to be 300,000 the United States to be 300,000 per year, with approximately per year, with approximately 75,000 (25%) of infected persons 75,000 (25%) of infected persons developing acute hepatitis.developing acute hepatitis.


Of these infected individuals, Of these infected individuals, 18,000-30,000 (6%-10%) will 18,000-30,000 (6%-10%) will become HBV carriers, at risk of become HBV carriers, at risk of developing chronic liver disease developing chronic liver disease (chronic active hepatitis, (chronic active hepatitis, cirrhosis, and primary liver cirrhosis, and primary liver cancer), and infectious to others.cancer), and infectious to others.


Before use of the HBV vaccine –Before use of the HBV vaccine –Approximately 12,000 health-care Approximately 12,000 health-care

workers became infected with HBV each workers became infected with HBV each year.year.


Before use of the HBV vaccine –Before use of the HBV vaccine – Approximately 12,000 health-care workers became Approximately 12,000 health-care workers became

infected with HBV each year.infected with HBV each year.

500-600 of them are hospitalized as a 500-600 of them are hospitalized as a result of HBV.result of HBV.



infected with HBV each year.infected with HBV each year. 500-600 of them are hospitalized as a result of HBV.500-600 of them are hospitalized as a result of HBV.

700-1,200 of those infected become 700-1,200 of those infected become HBV carriers.HBV carriers.



infected with HBV each year.infected with HBV each year. 500-600 of them are hospitalized as a result of HBV.500-600 of them are hospitalized as a result of HBV.

700-1,200 of those infected become HBV carriers.700-1,200 of those infected become HBV carriers. Of the infected workers, approximately Of the infected workers, approximately

250 will die (12-15 from fulminate 250 will die (12-15 from fulminate hepatitis, 170-200 from cirrhosis, and hepatitis, 170-200 from cirrhosis, and 40-50 from liver cancer).40-50 from liver cancer).


The annual number of The annual number of occupational infections has occupational infections has decreased 95% since hepatitis B decreased 95% since hepatitis B vaccine became available in vaccine became available in 1982, from >10,000 in 1983 to 1982, from >10,000 in 1983 to <400 in 2001.<400 in 2001.

Hepatitis B- TransmissionHepatitis B- Transmission

Hepatitis B is not spread Hepatitis B is not spread through:through:Food or waterFood or waterSharing eating utensilsSharing eating utensilsBreastfeedingBreastfeedingHugging or kissingHugging or kissingCoughing or sneezingCoughing or sneezingCasual contact.Casual contact.


HBV is spread throughHBV is spread through Having sex with an infected person Having sex with an infected person

without using a condom.without using a condom.


HBV is spread through:HBV is spread through: Having sex with an infected person Having sex with an infected person

without using a condom.without using a condom.The efficacy of latex condoms in preventing The efficacy of latex condoms in preventing

infection with HBV is unknown, but their infection with HBV is unknown, but their proper use should reduce transmission. proper use should reduce transmission.


HBV is spread through:HBV is spread through: Having sex with an infected person without using a Having sex with an infected person without using a

condom.condom.

Sharing drugs, needles, or drug Sharing drugs, needles, or drug paraphenalia.paraphenalia.


HBV is spread through:HBV is spread through: Having sex with an infected person without using a Having sex with an infected person without using a

condom.condom. Sharing drugs, needles, or drug paraphenalia.Sharing drugs, needles, or drug paraphenalia.

Needlesticks or sharps exposures Needlesticks or sharps exposures on the job.on the job.


HBV is spread through HBV is spread through Having sex with an infected person without using a Having sex with an infected person without using a

condom.condom. Sharing drugs, needles, or drug paraphenalia.Sharing drugs, needles, or drug paraphenalia. Needlesticks or sharps exposures on the job.Needlesticks or sharps exposures on the job.

HBV is spread from an infected HBV is spread from an infected mother to her baby during birth.mother to her baby during birth.


For a susceptible person, the For a susceptible person, the risk from a single needlestick or risk from a single needlestick or cut exposure to HBV-infected cut exposure to HBV-infected blood ranges from 6-30%.blood ranges from 6-30%.


Healthcare personnel who have Healthcare personnel who have received hepatitis B vaccine and received hepatitis B vaccine and developed immunity to the virus developed immunity to the virus are at virtually no risk for are at virtually no risk for infection. infection.


Saliva of some persons infected Saliva of some persons infected with HBV has been shown to with HBV has been shown to contain HBV-DNA at contain HBV-DNA at concentrations 1/1,000 to concentrations 1/1,000 to 1/10,000 of that found in the 1/10,000 of that found in the infected person's serum, but the infected person's serum, but the potential for salivary potential for salivary transmission of HBV is remote.transmission of HBV is remote.

Hepatitis B - DiagnosisHepatitis B - Diagnosis

Frequently a person with HBV Frequently a person with HBV infection has no symptoms at all infection has no symptoms at all or doesn’t recall anyor doesn’t recall anyOnly a blood test can tell for sure. Only a blood test can tell for sure.


HBsAg will be detected in an HBsAg will be detected in an infected person’s blood on the infected person’s blood on the average of 4 weeks (range 1-9 average of 4 weeks (range 1-9 weeks) after exposure to the weeks) after exposure to the virus.virus.


If symptoms occur, they occur on If symptoms occur, they occur on the average of 12 weeks (range the average of 12 weeks (range 9-21 weeks) after exposure to 9-21 weeks) after exposure to hepatitis B virus.hepatitis B virus. Symptoms occur in about 70% of Symptoms occur in about 70% of

patients, even though they may be mild patients, even though they may be mild and many HBV positive patients don’t and many HBV positive patients don’t recall any. recall any.


If you have symptoms, they If you have symptoms, they might include:might include:JaundiceJaundiceFatigue Fatigue Loss of appetite Loss of appetite Nausea Nausea Abdominal discomfort Abdominal discomfort Joint pain Joint pain

Interpretation of the Hepatitis B PanelInterpretation of the Hepatitis B Panel

TestsTests ResultsResults InterpretationInterpretation

HBsAgHBsAganti-HBcanti-HBcanti-HBsanti-HBs

negativenegativenegativenegativenegativenegative

SusceptibleSusceptible


negativenegativepositivepositivepositivepositive

Immune due to natural infectionImmune due to natural infection


negativenegativenegativenegativepositivepositive

Immune due to hepatitis B vaccinationImmune due to hepatitis B vaccination

HBsAgHBsAganti-HBcanti-HBc

IgM anti-HBcIgM anti-HBcanti-HBsanti-HBs

positivepositivepositivepositivepositivepositivenegativenegative

AcutelyAcutelyinfectedinfected

HBsAgHBsAganti-HBcanti-HBc

IgM anti-HBcIgM anti-HBcanti-HBsanti-HBs

positivepositivepositivepositivenegativenegativenegativenegative

ChronicallyChronically

infectedinfected


negativenegativepositivepositivenegativenegative

Recovering from acute HBV infection?Recovering from acute HBV infection?Slightly immune - test not sensitive enough to detect anti-Slightly immune - test not sensitive enough to detect anti-

HBsHBsSusceptible with a false positive anti-HBcSusceptible with a false positive anti-HBcUndetectable level of HBsAg present and the person is Undetectable level of HBsAg present and the person is

actually chronically infectedactually chronically infected



Hepatitis B e Antigen (HBeAg):Hepatitis B e Antigen (HBeAg): A secreted product of the nucleocapsid A secreted product of the nucleocapsid

gene of HBV and is found in serum gene of HBV and is found in serum during acute and chronic hepatitis B. Its during acute and chronic hepatitis B. Its presence indicates that the virus is presence indicates that the virus is replicating and the infected individual replicating and the infected individual has high levels of HBV. has high levels of HBV.


Hepatitis B e Antibody (HBeAb or Hepatitis B e Antibody (HBeAb or anti-HBe):anti-HBe): Produced by the immune system. Produced by the immune system.

Spontaneous conversion from e antigen Spontaneous conversion from e antigen to e antibody is a predictor of long-term to e antibody is a predictor of long-term clearance of HBV in patients undergoing clearance of HBV in patients undergoing antiviral therapy and indicates lower antiviral therapy and indicates lower levels of HBV. levels of HBV.

Hepatitis B - PreventionHepatitis B - Prevention


Hands and other skin surfaces Hands and other skin surfaces should be washed immediately should be washed immediately and thoroughly if contaminated and thoroughly if contaminated with blood, other body fluids to with blood, other body fluids to which standard precautions which standard precautions apply.apply.


Hands should always be washed Hands should always be washed after gloves are removed, even if after gloves are removed, even if the gloves appear to be intact.the gloves appear to be intact.


All spills of blood and blood-All spills of blood and blood-contaminated fluids should be contaminated fluids should be promptly cleaned up using an promptly cleaned up using an EPA-approved germicide or a EPA-approved germicide or a 1:10 solution of household 1:10 solution of household bleach while wearing gloves.bleach while wearing gloves.


All workers should take All workers should take precautions to prevent injuries precautions to prevent injuries caused by needles, scalpel blades, caused by needles, scalpel blades, and other sharp instruments or and other sharp instruments or devices during procedures; when devices during procedures; when cleaning used instruments; during cleaning used instruments; during disposal of used needles; and disposal of used needles; and when handling sharp instruments when handling sharp instruments after procedures.after procedures.


Infectious waste, in general, Infectious waste, in general, should either be incinerated or should either be incinerated or should be decontaminated should be decontaminated before disposal in a sanitary before disposal in a sanitary landfill.landfill.


Sharp items should be placed in Sharp items should be placed in puncture-proof containers and puncture-proof containers and other blood-contaminated items other blood-contaminated items should be placed in leak-proof should be placed in leak-proof plastic bags for transport to an plastic bags for transport to an appropriate disposal location.appropriate disposal location.


Available vaccines stimulate Available vaccines stimulate active immunity against HBV active immunity against HBV infection and provide over 90% infection and provide over 90% protection against hepatitis B for protection against hepatitis B for 7 or more years following 7 or more years following vaccination.vaccination.


In 1987, the Department of In 1987, the Department of Health and Human Services and Health and Human Services and the Department of Labor stated the Department of Labor stated that hepatitis B vaccine should that hepatitis B vaccine should be provided to all such workers be provided to all such workers at no charge to the worker.at no charge to the worker.


Hepatitis B vaccines also are Hepatitis B vaccines also are 70%-88% effective when given 70%-88% effective when given within 1 week after HBV within 1 week after HBV exposure. exposure.


Combination treatment with Combination treatment with hepatitis B vaccine and HBIG is hepatitis B vaccine and HBIG is over 90% effective in preventing over 90% effective in preventing hepatitis B following a hepatitis B following a documented exposure.documented exposure.


Who should receive the vaccine?Who should receive the vaccine?


Who should receive the vaccine?Who should receive the vaccine?All infants, at birth All infants, at birth


Who should receive the vaccine?Who should receive the vaccine? All babies, at birthAll babies, at birth All children 0-18 years of age who have All children 0-18 years of age who have

not been vaccinated not been vaccinated


Who should receive the vaccine?Who should receive the vaccine? All babies, at birth All babies, at birth All children 0-18 years of age who have not been All children 0-18 years of age who have not been

vaccinatedvaccinated People of any age whose behavior or job People of any age whose behavior or job

puts them at high risk for HBV infection.puts them at high risk for HBV infection.


Hepatitis B vaccines have been Hepatitis B vaccines have been shown to be safe when shown to be safe when administered to both adults and administered to both adults and children.children.


Neither pregnancy nor Neither pregnancy nor breastfeeding should be breastfeeding should be considered a contraindication to considered a contraindication to vaccination of women.vaccination of women.


Persons allergic to yeast should Persons allergic to yeast should not be vaccinated with vaccines not be vaccinated with vaccines containing yeast.containing yeast.


Recent studies indicate that Recent studies indicate that immunologic memory remains immunologic memory remains intact for at least 23 years and intact for at least 23 years and confers protection against confers protection against clinical illness and chronic HBV clinical illness and chronic HBV infection.infection.


Who should get post-vaccination Who should get post-vaccination testing?testing?


Who should get post-vaccination Who should get post-vaccination testing?testing?Testing for immunity is advised only for Testing for immunity is advised only for

persons whose subsequent clinical persons whose subsequent clinical management depends on knowledge of management depends on knowledge of their immune status. their immune status.


Who should get post-vaccination Who should get post-vaccination testing?testing?When indicated, post-vaccination When indicated, post-vaccination

testing, using the anti-HBs test, should testing, using the anti-HBs test, should be performed 1 to 2 months after be performed 1 to 2 months after completion of the vaccine series. completion of the vaccine series.

Hepatitis B – Post-Exposure Hepatitis B – Post-Exposure ManagementManagement

For an exposure to a source For an exposure to a source individual found to be positive for individual found to be positive for HBsAg, the worker HBsAg, the worker who has not who has not previously been given hepatitis B previously been given hepatitis B vaccinevaccine should receive should receive The vaccine series. The vaccine series. A single dose of hepatitis B immune A single dose of hepatitis B immune

globulin (HBIG), if given within 7 days of globulin (HBIG), if given within 7 days of exposure. exposure.


For exposures from an HBsAg-For exposures from an HBsAg-positive source to workers positive source to workers who who have previously received have previously received vaccinevaccine::Test for antibody to hepatitis B surface Test for antibody to hepatitis B surface

antigen (anti-HBs)antigen (anti-HBs)Given one dose of vaccine and one dose Given one dose of vaccine and one dose

of HBIG if the antibody level in the of HBIG if the antibody level in the worker's blood sample is inadequate.worker's blood sample is inadequate.


If the source individual is If the source individual is negative for HBsAg and the negative for HBsAg and the worker has not been vaccinated, worker has not been vaccinated, this opportunity should be taken this opportunity should be taken to provide hepatitis B to provide hepatitis B vaccination. vaccination.

Hepatitis B - TreatmentHepatitis B - Treatment

There are no medications There are no medications available for recently acquired available for recently acquired (acute) HBV infection.(acute) HBV infection.

Hepatitis B - TreatmentHepatitis B - Treatment

There are antiviral drugs There are antiviral drugs available for the treatment of available for the treatment of chronic HBV infection.chronic HBV infection.

Hepatitis DHepatitis D

Hepatitis D virus requires Hepatitis B virus Hepatitis D virus requires Hepatitis B virus for replication.for replication.

Hepatitis D is prevented with HBV vaccineHepatitis D is prevented with HBV vaccine

Let’s take a short break!Let’s take a short break!

Hepatitis C - Description of the Hepatitis C - Description of the agentagent

The infection is often The infection is often asymptomatic, but ensuing asymptomatic, but ensuing chronic hepatitis can result later chronic hepatitis can result later in cirrhosis and liver cancer.in cirrhosis and liver cancer.


The The Hepatitis C virusHepatitis C virus (HCV) is a (HCV) is a small (50 nm in size), enveloped, small (50 nm in size), enveloped, single-stranded, positive sense single-stranded, positive sense RNA virus in the families RNA virus in the families Flaviviridae.Flaviviridae.


The The FlaviviridaeFlaviviridae are a family of are a family of viruses that are primarily spread viruses that are primarily spread through arthropod vectors.through arthropod vectors.West Nile Encephalitis virusWest Nile Encephalitis virusYellow fever virusYellow fever virusSt. Louis Encephalitis virusSt. Louis Encephalitis virus

Hepatitis C - HistoryHepatitis C - History

In the 1970’s what is now known In the 1970’s what is now known as hepatitis C was called as hepatitis C was called non-A, non-A, non-B hepatitisnon-B hepatitis (NANBH). (NANBH).


In 1987 Michael Houghton, Qui-In 1987 Michael Houghton, Qui-Lim Choo, and George Kuo at Lim Choo, and George Kuo at Chiron Corporation utilized Chiron Corporation utilized molecular methods to identify molecular methods to identify the unknown organism.the unknown organism.


In 1988, the virus was confirmed In 1988, the virus was confirmed as a cause of non-A non-B as a cause of non-A non-B hepatitis by Alter who verified hepatitis by Alter who verified its presence in a panel of NANBH its presence in a panel of NANBH specimens. specimens.


April of 1989, the discovery of April of 1989, the discovery of the virus, re-named hepatitis C the virus, re-named hepatitis C virus (HCV), was published in virus (HCV), was published in two articles in the journal two articles in the journal ScienceScience. .

Hepatitis C - PrevalenceHepatitis C - Prevalence

The incidence of hepatitis C has The incidence of hepatitis C has declined steadily since peaking declined steadily since peaking in the late 1980s. in the late 1980s.


Hepatitis C is the leading cause Hepatitis C is the leading cause of liver transplants in the United of liver transplants in the United States.States.


Hepatitis C infects an estimated Hepatitis C infects an estimated 170 million people worldwide 170 million people worldwide and 4 million in the United and 4 million in the United States.States.


There are about 35,000 to There are about 35,000 to 185,000 new cases a year in the 185,000 new cases a year in the United States.United States.


Co-infection with HIV is commonCo-infection with HIV is common. . Approximately 350,000 of patients in Approximately 350,000 of patients in

the USA infected with HIV are also the USA infected with HIV are also infected with the hepatitis C virus.infected with the hepatitis C virus.


There are numerous cases of There are numerous cases of Hepatitis C in southern Ohio – a Hepatitis C in southern Ohio – a higher rate per capita than other higher rate per capita than other areas.areas.

Hepatitis C - DiagnosisHepatitis C - Diagnosis

Acute hepatitis C refers to the Acute hepatitis C refers to the first 6 months after infection first 6 months after infection with HCV.with HCV.


Acute hepatitis C refers to the first 6 months after Acute hepatitis C refers to the first 6 months after

infection with HCV.infection with HCV. Between 60% to 70% of people Between 60% to 70% of people

infected develop no symptoms infected develop no symptoms during the acute phase.during the acute phase.


Acute hepatitis C refers to the first 6 months after Acute hepatitis C refers to the first 6 months after infection with HCV. infection with HCV.

Between 60% to 70% of people infected develop Between 60% to 70% of people infected develop

no symptoms during the acute phase.no symptoms during the acute phase. In the patients who experience In the patients who experience

acute phase symptoms, they are acute phase symptoms, they are generally mild and nonspecific, generally mild and nonspecific, and rarely lead to a specific and rarely lead to a specific diagnosis of hepatitis C.diagnosis of hepatitis C.


The hepatitis C virus is usually The hepatitis C virus is usually detectable in the blood within detectable in the blood within one to three weeks after one to three weeks after infection.infection.


Approximately 20-30% of Approximately 20-30% of persons infected with HCV clear persons infected with HCV clear the virus from their bodies the virus from their bodies during the acute phase.during the acute phase.


Many patients positive for Many patients positive for Hepatitis C virus should also be Hepatitis C virus should also be tested for HIV infection.tested for HIV infection.

Heptatits C – DiagnosisHeptatits C – Diagnosis

The detection of anti-HCV The detection of anti-HCV antibodies in plasma or serum is antibodies in plasma or serum is based on the use of enzyme based on the use of enzyme immunoassays (EIA).immunoassays (EIA).Anti-HCV antibodies always persist for Anti-HCV antibodies always persist for

life in patients who develop chronic life in patients who develop chronic infection. infection.


70-80% of patients infected with 70-80% of patients infected with HCV develop chronic hepatitis C, HCV develop chronic hepatitis C, (infection lasting more than 6 (infection lasting more than 6 months). months).


70-80% of patients infected with HCV develop 70-80% of patients infected with HCV develop chronic hepatitis C, (infection lasting more than 6 chronic hepatitis C, (infection lasting more than 6

months).months). Liver biopsy is the best test to Liver biopsy is the best test to

determine the amount of determine the amount of scarring and inflammation.scarring and inflammation.


Anti-HCV antibodies can be Anti-HCV antibodies can be detected in:detected in:80% of patients within 15 weeks after 80% of patients within 15 weeks after

exposureexposure>90% within 5 months after exposure>90% within 5 months after exposure>97% by 6 months after exposure. >97% by 6 months after exposure.


Anti-HCV antibodies indicate Anti-HCV antibodies indicate exposure to the virus, but exposure to the virus, but cannotcannot determine if ongoing infection is determine if ongoing infection is present.present.


Anti-HCV antibodies indicate exposure to Anti-HCV antibodies indicate exposure to the virus, but the virus, but cannotcannot determine if ongoing determine if ongoing infection is present.infection is present.

The presence of the virus is The presence of the virus is tested for using molecular tested for using molecular nucleic acid testing methods nucleic acid testing methods (PCR, TMA, or branched DNA (b-(PCR, TMA, or branched DNA (b-DNA))DNA))


Anti-HCV antibodies indicate exposure to the Anti-HCV antibodies indicate exposure to the virus, but virus, but cannotcannot determine if ongoing infection is determine if ongoing infection is present. present.

The presence of the virus is tested for using The presence of the virus is tested for using molecular nucleic acid testing methods (PCR, molecular nucleic acid testing methods (PCR, TMA, or branched DNA (b-DNA))TMA, or branched DNA (b-DNA))

All HCV nucleic acid molecular tests All HCV nucleic acid molecular tests have the capacity to detect not only have the capacity to detect not only whether the virus is present, but also whether the virus is present, but also to measure the amount of virus to measure the amount of virus present in the blood.present in the blood.

Hepatitis C – Chronic infectionHepatitis C – Chronic infection

Among untreated patients, Among untreated patients, roughly one-third progress to roughly one-third progress to liver cirrhosis in less than 20 liver cirrhosis in less than 20 years.years.


Among untreated patients, roughly one-third Among untreated patients, roughly one-third

progress to liver cirrhosis in less than 20 years.progress to liver cirrhosis in less than 20 years. Another third progress to Another third progress to

cirrhosis within 30 years.cirrhosis within 30 years.


Among untreated patients, roughly one-third Among untreated patients, roughly one-third progress to liver cirrhosis in less than 20 years. progress to liver cirrhosis in less than 20 years.

Another third progress to cirrhosis within 30 Another third progress to cirrhosis within 30

years.years. The remainder of patients The remainder of patients

appear to progress so slowly appear to progress so slowly that they are unlikely to develop that they are unlikely to develop cirrhosis within their lifetimes.cirrhosis within their lifetimes.

Hepatitis C - TransmissionHepatitis C - Transmission

In 2005, injection-drug use In 2005, injection-drug use continued to be the most continued to be the most commonly identified risk factor commonly identified risk factor for infection.for infection.


Studies conducted to evaluate Studies conducted to evaluate the role of sexual transmission the role of sexual transmission of HCV have indicated that the of HCV have indicated that the virus is spread inefficiently virus is spread inefficiently through this route, although it through this route, although it does occur.does occur.

Hepatitis - TransmissionHepatitis - Transmission

HCV is HCV is notnot spread through: spread through: Casual contact Casual contact Hugging or kissingHugging or kissingSharing eating or cooking utensils.Sharing eating or cooking utensils.

Hepatitis - TransmissionHepatitis - Transmission

HCV is spread by:HCV is spread by: illicit drug useillicit drug useOccupational expose to bloodOccupational expose to bloodBody piercing and tatoosBody piercing and tatoosMother-to-child transmission of hepatitis Mother-to-child transmission of hepatitis

C occurs relatively infrequently. C occurs relatively infrequently. Blood transfusions - rare today because Blood transfusions - rare today because

blood supply is tested for HCV.blood supply is tested for HCV.

Hepatitis C - PreventionHepatitis C - Prevention

There is no vaccination that There is no vaccination that protects against contracting protects against contracting Hepatitis C.Hepatitis C.

Hepatitis C - PreventionHepatitis C - Prevention

Avoid high risk activities and Avoid high risk activities and contact with blood from infected contact with blood from infected individuals.individuals.

Hepatitis C – Post-ExposureHepatitis C – Post-Exposure

Determine status of source of Determine status of source of exposure, if negative, no exposure, if negative, no additional testing necessaryadditional testing necessary


If source is positive:If source is positive:Baseline testing at time of exposureBaseline testing at time of exposure


If source is positive:If source is positive:If baseline is negative, test at 3 monthsIf baseline is negative, test at 3 months


If source is positive:If source is positive:If employee was negative at 3 months, If employee was negative at 3 months,

test again at 6 months.test again at 6 months.

Hepatitis C - TreatmentHepatitis C - Treatment

There is a very small chance of There is a very small chance of clearing the virus spontaneously clearing the virus spontaneously (0.5 to 0.74% per year).(0.5 to 0.74% per year).


Current treatment is a Current treatment is a combination of pegylated combination of pegylated interferon alpha (brand names interferon alpha (brand names Pegasys and PEG-Intron) and Pegasys and PEG-Intron) and ribaviron for a period of 24 or 48 ribaviron for a period of 24 or 48 weeks, depending on genotype.weeks, depending on genotype.


Those with low initial viral loads Those with low initial viral loads respond much better to respond much better to treatment than those with treatment than those with higher viral loads (greater than 2 higher viral loads (greater than 2 million virons/ml). million virons/ml).


The treatment may be physically The treatment may be physically demanding, particularly those demanding, particularly those with a prior history of drug or with a prior history of drug or alcohol abuse.alcohol abuse.The drop-out rate for treatment of The drop-out rate for treatment of

hepatitis C treatment is high.hepatitis C treatment is high.

Fast Break?Fast Break?

Infection ControlInfection Control

Infection Control - Standard Infection Control - Standard PrecautionsPrecautions

General infection-control General infection-control procedures are designed to procedures are designed to prevent transmission of a wide prevent transmission of a wide range of microbiological agents range of microbiological agents and to provide a wide margin of and to provide a wide margin of safety in the varied situations safety in the varied situations encountered in the health-care encountered in the health-care environment.environment.

Infection Control Policies, Infection Control Policies, Procedure and DocumentationProcedure and Documentation

Most important Aspect - Common Most important Aspect - Common SenseSense


Most important Aspect - Common SenseMost important Aspect - Common Sense

Standard precautionsStandard precautions


Most important Aspect - Common SenseMost important Aspect - Common Sense Standard precautionsStandard precautions

Specific infection control and Specific infection control and isolation requirements fro isolation requirements fro specific infectionsspecific infections

Standard PrecautionsStandard Precautions

Use the appropriate barrierUse the appropriate barrier


Use the appropriate barrierUse the appropriate barrier

Use proper hand hygieneUse proper hand hygieneAlcohol hand sanitizerAlcohol hand sanitizerSoap and waterSoap and water


Use the appropriate barrierUse the appropriate barrier Use proper hand hygieneUse proper hand hygiene

Alcohol hand sanitizerAlcohol hand sanitizer Soap and waterSoap and water

Do not eat, drink, smoke, apply Do not eat, drink, smoke, apply cosmetics, or handle contact cosmetics, or handle contact lenses in an area where there is lenses in an area where there is a possibility of exposure to an a possibility of exposure to an infectious agent.infectious agent.


Use the appropriate barrierUse the appropriate barrier Use proper hand hygieneUse proper hand hygiene

Alcohol hand sanitizerAlcohol hand sanitizer Soap and waterSoap and water

Do not eat, drink, smoke, apply cosmetics, or Do not eat, drink, smoke, apply cosmetics, or handle contact lenses in an area where there is a handle contact lenses in an area where there is a possibility of exposure to an infectious agent.possibility of exposure to an infectious agent.

Careful handling of sharp objectsCareful handling of sharp objects

DisinfectantsDisinfectants

What is the best overall What is the best overall disinfectant?disinfectant?


What is the best overall What is the best overall disinfectant?disinfectant?Sodium hypochlorite – a 1:10 dilution of Sodium hypochlorite – a 1:10 dilution of

household bleach with 5% sodium household bleach with 5% sodium hypochlorite.hypochlorite.

Must be made fresh dailyMust be made fresh dailyDispatch – stabilized Na hypochloriteDispatch – stabilized Na hypochlorite


What about Sanicloths?What about Sanicloths?Good for electrical equipment and things Good for electrical equipment and things

that bleach would deteriorate.that bleach would deteriorate.Not as good of a disinfectant as bleach.Not as good of a disinfectant as bleach.

GlovesGloves

Not a replacement for Not a replacement for handwashinghandwashing

GlovesGloves

Not a replacement for handwashingNot a replacement for handwashing

Use when exposure to blood or a Use when exposure to blood or a body fluid is anticipated.body fluid is anticipated.

GlovesGloves

Not a replacement for handwashingNot a replacement for handwashing Use when exposure to blood or a body fluid is Use when exposure to blood or a body fluid is

anticipated.anticipated.

Only single-use gloves should be Only single-use gloves should be used in patient care.used in patient care.

GlovesGloves

Not a replacement for handwashingNot a replacement for handwashing Use when exposure to blood or a body fluid is Use when exposure to blood or a body fluid is

anticipated.anticipated. Only single-use gloves should be used in patient Only single-use gloves should be used in patient

care.care.

Gloves used in patient care (ie. Gloves used in patient care (ie. single use) should not be washed single use) should not be washed or disinfected and re-used.or disinfected and re-used.

Disposal of SharpsDisposal of Sharps

Most sharps injuries are Most sharps injuries are avoidable!avoidable!


Most sharps injuries are avoidable!Most sharps injuries are avoidable!

Most people who are injured Most people who are injured with sharps were not the with sharps were not the persons using the sharp!persons using the sharp!


Place sharps immediately into an Place sharps immediately into an impervious sharps container.impervious sharps container.Do not leave needles lying on beds or in Do not leave needles lying on beds or in

linens or put into regular trashlinens or put into regular trashDo not recap needles (except for some Do not recap needles (except for some

special use needles, then there should special use needles, then there should not be picked up to recap).not be picked up to recap).


Place sharp object in sharp Place sharp object in sharp container with needle facing container with needle facing down.down.


Place sharp object in sharp container with needle Place sharp object in sharp container with needle facing down.facing down.

Do not overfill a sharps Do not overfill a sharps container.container.


Place sharp object in sharp container with needle Place sharp object in sharp container with needle facing down.facing down.

Do not overfill a sharps container.Do not overfill a sharps container.

When possible, sharps When possible, sharps containers should no be containers should no be accessible to patientsaccessible to patients

Infection Control – OSHA Infection Control – OSHA RequirementsRequirements

Employers should make Employers should make protective equipment available protective equipment available to all workers when they are to all workers when they are engaged in Category I or II engaged in Category I or II activities.activities.


Employers should ensure that Employers should ensure that the appropriate protective the appropriate protective equipment is used by workers equipment is used by workers when they perform Category I when they perform Category I activities.activities.


Employers should establish a Employers should establish a detailed work practices program detailed work practices program that includes standard operating that includes standard operating procedures (SOPs) for all procedures (SOPs) for all activities having the potential activities having the potential for exposure.for exposure.


Employers should monitor the Employers should monitor the workplace to ensure that workplace to ensure that required work practices are required work practices are observed and that protective observed and that protective clothing and equipment are clothing and equipment are provided and properly used.provided and properly used.


In addition, training records, In addition, training records, indicating the dates of training indicating the dates of training sessions, the content of those sessions, the content of those training sessions along with the training sessions along with the names of all persons conducting names of all persons conducting the training, and the names of the training, and the names of all those receiving training all those receiving training should also be maintained. should also be maintained.


All workers whose jobs involve All workers whose jobs involve participation in tasks or participation in tasks or activities with exposure to blood activities with exposure to blood or other body fluids to which or other body fluids to which universal precautions apply universal precautions apply should be vaccinated with should be vaccinated with hepatitis B vaccine.hepatitis B vaccine.

TuberculosisTuberculosis

Tuberculosis - HistoryTuberculosis - History

In 1900 TB was the leading cause In 1900 TB was the leading cause of death in the U.S. of death in the U.S.


Nationwide, from the late 40’s Nationwide, from the late 40’s the incidence decreased until the incidence decreased until 1984.1984. Cases decreased such that it was Cases decreased such that it was

thought that TB would be a historic thought that TB would be a historic disease by 2005.disease by 2005.


Cases began to increase in 1985, Cases began to increase in 1985, mainly due to HIV and MDR mainly due to HIV and MDR strains.strains.

Tuberculosis - PrevalenceTuberculosis - Prevalence

An estimated 10-15 million An estimated 10-15 million Americans are infected with Americans are infected with Mycobacterium tuberculosisMycobacterium tuberculosis


About 10 percent of these About 10 percent of these infected individuals (that do not infected individuals (that do not receive prophylaxis) will develop receive prophylaxis) will develop TB at some point in their lives.TB at some point in their lives.


Locally, we have a low rate of Locally, we have a low rate of tuberculosis – 1-3 new cases per tuberculosis – 1-3 new cases per year. year.

Tuberculosis – Latent vs. Tuberculosis – Latent vs. ActiveActive

Two forms of the Two forms of the diseasedisease Latent tuberculosis - Latent tuberculosis -

positive PPD only, no positive PPD only, no symptoms, cannot spread symptoms, cannot spread to others to others

Tuberculosis – Latent vs. Tuberculosis – Latent vs. ActiveActive

Two forms of the Two forms of the diseasedisease Active tuberculosis – Active tuberculosis –

symptoms are present – symptoms are present – can spread to others if can spread to others if pulmonary infection.pulmonary infection.

Infection via inhalation of droplets containing M. tuberculosis

Bacteria are engulfed by macrophages, but not killed

Initial symptoms – 1-2 weeks following infection

Dissemination to other organs via lymphatics

Pneumonic symptoms resolve

Cellular immunity develops - PPD turns positive

Dissemination ceases

Immunocompetent host

Most bacteria are killed by macrophages

Latent disease – bacteria may remain viable for years

Immunosuppressed host

ACTIVE

TUBERCULOSIS

Immunosuppression


Can be (and usually is) carried Can be (and usually is) carried for a long time before onset of for a long time before onset of active disease.active disease.


Transmitted by inhaling infected Transmitted by inhaling infected droplets from a person with droplets from a person with active pulmonary tuberculosis.active pulmonary tuberculosis.


With active TB, respiratory With active TB, respiratory isolation and standard isolation and standard precautions are used to prevent precautions are used to prevent spread of infection. spread of infection.

Tuberculosis - TypesTuberculosis - Types

Causes a wide variety of Causes a wide variety of infections, such as pulmonary infections, such as pulmonary infections, skin and sinus tract infections, skin and sinus tract infections, renal infections, infections, renal infections, osteomyelitis, non-specific osteomyelitis, non-specific lymphatic disease.lymphatic disease.

Tuberculosis – Relationship to Tuberculosis – Relationship to HIVHIV

Because HIV infection weakens Because HIV infection weakens the immune system, people the immune system, people infected with HIV and TB have a infected with HIV and TB have a 100 times greater risk of 100 times greater risk of developing active TB disease developing active TB disease compared to people not infected compared to people not infected with HIV.with HIV.


TB is the cause of death for one TB is the cause of death for one out of every three people with out of every three people with AIDS worldwide.AIDS worldwide.


The spread of the HIV epidemic The spread of the HIV epidemic has significantly impacted the TB has significantly impacted the TB epidemic. epidemic.


Individuals that are HIV positive Individuals that are HIV positive may not test correctly with PPD.may not test correctly with PPD.


Individuals that have HIV and Individuals that have HIV and active TB have more organisms active TB have more organisms and are a greater threat to and are a greater threat to spread the disease.spread the disease.


All people infected with HIV All people infected with HIV should be tested for TB, and, if should be tested for TB, and, if infected, complete preventive infected, complete preventive therapy as soon as possible to therapy as soon as possible to prevent TB disease.prevent TB disease.

Tuberculosis - MDRTuberculosis - MDR

For active TB, treatment usually For active TB, treatment usually with 3-4 medications to prevent with 3-4 medications to prevent selection of resistant TB strains. selection of resistant TB strains.

For latent TB, treatment for 6 For latent TB, treatment for 6 months with INH alone, if months with INH alone, if tolerated.tolerated.

Questions or Comment?Questions or Comment?

ReferencesReferences

Most of the information for this Most of the information for this presentation was taken from the CDC presentation was taken from the CDC website at website at http://www.cdc.gov/http://www.cdc.gov/ and and included references from included references from Morbidity Morbidity and Mortality Weeklyand Mortality Weekly report and report and Emerging Infectious DiseasesEmerging Infectious Diseases

Thanks to our sponsor!Thanks to our sponsor!Scioto County Medical SocietyScioto County Medical Society

Thank you for your time and Thank you for your time and attention!attention!

It has been a pleasure to be It has been a pleasure to be with you this evening!with you this evening!

blood-borne pathogens, tuberculosis update, and infection control timothy r. cassity, ph. d....

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