no relevant disclosures - johns hopkins hospital · 07/03/2014 2 objectives • discuss...

07/03/2014

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Influenza, TB, Pertussis and Other Respiratory Diseases

Ann-Christine Nyquist MD, MSPHProfessor of Pediatrics, Sections of Infectious Diseases and

EpidemiologyMedical Director, Infection Prevention and Control and

Occupational Health

18th Annual Fellow’s Course in Hospital Epidemiology and Infection Control

July 9, 2014

Disclosures

No Relevant Disclosures

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Objectives

• Discuss epidemiology, diagnosis and transmission of respiratory viruses, pertussis, and TB

• Highlight the role of respiratory viruses, pertussis, TB as causes of nosocomial infections

• Review methods to prevent healthcare-associated respiratory viral infections, pertussis, and TB

Respiratory Viruses

• Influenza

• RSV

• Human metapneumovirus

• Coronaviruses

• Rhinoviruses

• Adenoviruses

• Bocavirus

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Jul Aug Sept Oct Nov Dec Jan Feb Mar Apr May Jun

Seasonal Incidence of Common ChildhoodInfections

Diseases of Infancy and ChildhoodTextbook L. Emmett Holt 1906

Chapter XII Influenza synonym: la grippe

Influenza is an infectious, communicable disease, which is now generally admitted to be due to the bacillus described by Pfeiffer in 1892.

Treatment…..The fumigation of apartments after attacks should be regularly practiced, preferably with formalin gas; this with isolation will do much to control house epidemics…The cough which persists after influenza is best controlled by cod-liver oil and creosote, used as after acute bronchitis.

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Influenza Virus

15th Century Italians– “to influence”; illness influenced by

the stars and planets

Family Orthomyxoviridae– “myxo” mucus– enveloped, segmented, single-

stranded RNA

Influenza A first isolated 1933; Influenza B 1940

15 hemagglutinin (HA) and 9 neuraminidase (NA) subtypes– Only H1N1, H2N2, H3N2 subtypes

associated with widespread epidemics in humans

Clinically Relevant Influenza Viruses Type A Potentially severe illness

Epidemics and pandemicsRapidly changingBirds, swine, horses, seals, humans

Type B Usually less severe illnessEpidemicsMore uniformHumans

Type C Usually mild or asymptomatic illness Minimal public health impactHumans, swine

Centers for Disease Control and Prevention. Influenza Prevention and Control. Influenza. Available at: http://www.cdc.gov/ncidod/diseases/flu/fluinfo.htm.

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Influenza: A Continuously Changing Virus

Polymerase Proteins (PP)

Hemagglutinin (HA) *cell entry

Neuraminidase (NA)*cell escape

M1, M2

Nucleoprotein (NP)

Adapted from: Hayden FG et al. Clin Virol. 1997:911-942.

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RNA

Hemagglutinin

NeuraminidaseAntibodies

Sialic acid

Antigenic Drift (A & B)

Antigenic Shift (A only)

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15 countries 553 cases - 323 deaths

Update March 2013: Avian influenza A (H7N9)

Avian Influenza: Sick Chickens

Blue Comb

Swollen Wattle

Congestion and Blood Spots on

Hocksand Shanks

Vesicleson comb

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Transmission of Influenza Person to person Droplet spread-

– small particle aerosols Fomite contamination

– Steel and plastic 24-48 hrs– Cloth,paper,tissues 8-12 hrs– Hands 5 min (high viral titer)

Principal site of replication- columnar epithelium Incubation period- 18 hrs to 5 or more days (avg 2-3 days) Virus shedding 3-7 days Viral titers are generally higher in young children with shedding

lasting 10 days or longer

Children are a “Vector”

Influenza uniquely allows children to spread its virus– children less sick than adults– Higher viral titer– longer viral excretion

School-age children have the highest attack rates of influenza– disease rates peak first in children during an outbreak

Schools facilitate the infection– 1918 and 1957 first cases appeared in the spring but real

outbreaks began in fall after school began– 1968 pandemic mild- “interrupted” by school holiday break

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Influenza Symptoms by Age Group

Influenza Sign/Symptom Children Adults Elderly

Cough (nonproductive) ++ ++++ +++

Fever +++ +++ +

Myalgia + ++ +

Headache ++ ++ +

Malaise + ++ +++

Sore throat + ++ +

Rhinitis/nasal congestion ++ ++ +

Abdominal pain/diarrhea + – +

Nausea/vomiting ++ – +

++++ Most frequent sign/symptom; + Least frequent; – Infrequent

Monto AS, et al. Arch Intern Med. 2000;160:3243-3247; Cox NJ, Subbarao K. Lancet. 1999;354:1277-1282.

Role of Children in Influenza Epidemiology

Adapted from: Elveback LR et al. Am J Epidemiol. 1976;103:152-165.

Family members &other close contacts

Other children

Day care, preschool and school-age children

Communityincluding high-risk populations

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Talbot TR ICHE 2005;26:882 Stott DJ Occ Med 2002;52:249 Foy HM Am J Epi 1987;126:506 Weingarten S AJIC 1989;17:202 Lester RT ICHE 2003;24:839

Healthcare-Associated Influenza

• Outbreaks reported in most care areas

• Influenza infection causes minimal or nosymptoms in up to 25%

• Such workers still shed (and spread) virus

• 76.6% HCP work while ill with ILI

• Worked mean 2.5 days while ill with ILI

Risk of HA-ILI in Acute Care Setting

Vanhems P et al Arch Intern Med 2011;171:151+

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Transmission of Respiratory Pathogens

• Some pathogens can be spread by various sizes of particles that travel in the air Larger droplets

• Pertussis (whooping cough)

• Influenza

Smaller aerosols• M. tuberculosis

• Direct spread via contact with the environment is also suspected

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Moghadas SM et al BMC Medicine 2009;7:73+

Influenza Shedding

How Long Are Surfaces Contaminated ?

RSV survives on environmental surfaces – 7 hours on countertops– 5 hours on gloves– 2 hours on cloth– 30 minutes on skin and paper tissue

RSV can be cultured from hands for up to 25 minutes after contact with contaminated surfaces

Cultured from stethoscopes, hospital environment

Rotavirus survives for up to 7 months on surfaces, weeks in water and for up to 4 hours on human hands

Influenza survives for up to 24-48 hrs on steel and plastic, 8-12 hrs on cloth/paper tissues and 5 minutes on hands (high viral titer)

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Prevention of Healthcare-Associated Respiratory Viral Infections

• Hand Hygiene/Respiratory Hygiene & Cough Etiquette

• Early Identification of Cases

• Patient Cohorting

• Source Control

• Isolation Precautions/PPE

• Antivirals

• Vaccination





• Source Control


• Antivirals

• Vaccination

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Respiratory Hygieneand Cough Etiquette

• Cover your mouth and nose when you cough or sneeze.

• Practice good hand hygiene at all times.

• Keep 6 feet or more between you and anyone with respiratory symptoms unless wearing appropriate protection.





• Source Control


• Antivirals

• Vaccination

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Early Identification of Cases

• Screening for symptoms at facility entry Both patients & visitors

Clinical Presentation: ILI and Laboratory-Confirmed Influenza

Babcock HM et al 2006;27:266+

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Influenza: Diagnosis• Gold standard = isolation of virus from

respiratory secretions Takes 3-5 days to isolate

• Viral antigen detection: Various assays used (IF, RIA, ELISA) Low sensitivity for nH1N1, H5N1 and in

extremes of age

• PCR• Serology: Requires paired samples, 10-14 days apart

Source Control

• Place surgical mask on patient

• Data from households and dormitories have found use of masks reduce transmission of ILI

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Prevention of Healthcare-Associated Respiratory Viral Infections• Hand Hygiene/Respiratory Hygiene & Cough

Etiquette



• Source Control


• Antivirals

• Vaccination

CDC Transmission-Based Precautions

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N-95 vs. Mask

• Keeps small droplets from going IN

• A respirator

• Filters particles 1 m with a filter efficiency of >95%

• Not effective if wet

• Fit-test annually

• Keeps large droplets from going IN

• Keeps air, secretions, YOUR viral infection from going OUT

N-95 Mask

Loeb M et al JAMA 2009;302:1865+

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PPE: Respiratory Viruses

Virus Type of Precautions

Seasonal Influenza Droplet

RSV Contact

hMPV Contact

Rhinovirus Droplet

Parainfluenza Contact

SARS-HCoV Contact, Airborne, Eye Protection

Other HCoV ??? Contact or Droplet


Etiquette



• Source Control


• Antivirals

• Vaccination

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Influenza Antivirals

Adamantanes– Amantidine & rimantidine– M2 ion channel inhibitors– Effective against type A viruses only (Rx & prophylaxis)

Neuraminidase inhibitors– Oseltamivir (Tamiflu) & zanamivir (Relenza)– Effective against type A & B viruses (Rx & prophylaxis)

Issues– Resistance among seasonal influenza viruses– Resistance among some H5N1 viruses– None approved for Rx or prophylaxis for children < 1yr– Unproven effectiveness for Rx of H5N1 infection


Etiquette



• Source Control


• Antivirals

• Vaccination

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Comparing IIV and LAIV

Administration Intramuscular Intranasal

Immune response Serum antibodies Serum antibodies, Mucosal immunity, ? Cellular immunity

Efficacy childrenEfficacy adults <65 y

~30-70%70-90%

70-90%70-90%

Virus Split-virus or subunit inactivated virus

Cold-adapted, temperature-sensitive, live attenuated virus

Growth medium Chick embryos Chick embryos

Indication Any person 6 mo Healthy persons 5-49 yrs

Category IIV LAIV

Talbot TR et al ICHE 2005;26:882+

• Frequent contact with high-risk patients

• Serve as a vehicle for spread of flu

• HCP absenteeism can stress health system

• Influenza vaccination of HCP may reduce patient mortality

• Model for patients

Why is Healthcare Personnel Influenza Vaccination Important?

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Why Physicians Work When Sick?

Published Online: June 18, 2012. doi:10.1001/archinternmed.2012.1998

Pertussis

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Pertussis (Whooping Cough)• Bordetella pertussis – gm-neg

pleomorphic bacillus• Humans only known host• Transmission via contact with

respiratory secretions (droplet precautions)

• Incubation period 6-20 days (usually 7-10 days) Catarrhal stage (mild URI

sx- most contagious) Paroxysmal stage (severe cough, whoop) Convalescent stage

• Duration 6-10 weeks

When Is Pertussis Communicable?

• Persons with pertussis become highly infectious during the catarrhal stage.

• Some individuals, especially infants, may be infectious for a longer period than shown above.

Reference:1. CDC. The Pink Book. 10th ed. 2007:81-100. Available at: http://www.cdc.gov/vaccines/pubs/pinkbook/downloads/pert.pdf. Accessed September 17, 2007.

-2 -1 0 1 2 3 4 5 6 7 8 9 10 11 12

Weeks of cough

Catarrhal stage

Paroxysmal stage

Convalescent stage

Paroxysmal cough onset

Typical period of communicability

Exposure

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Dramatic Growth inReports of Adult and Adolescent Pertussis

References:1. Güriş D, et al. Clin Infect Dis. 1999;28:1230-1237. 2. CDC. MMWR. 2002;51(4):73-76. 3. CDC. MMWR. 2003;50(53):9.4. CDC. MMWR. 2004;51(53):23. 5. CDC. MMWR. 2005;54(31):777. 6. National Center for Immunization and Respiratory Diseases, CDC. Pertussis Surveillance Reports for 2004 & 2005.

1990-19931 1994-19961 1997-20002 2001-20033-5 2004-20056

8000

9000

0

4000

1000

5000

2000

6000

3000

7000

<1 yr 1-4 yrs 5-9 yrs 10-19 yrs 20+ yrs

Ave

rag

e N

um

ber

of

Cas

es /

Yea

r

Age Group

15.6fold

16.7 fold

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Transmission of Pertussis

Adults

Adolescents

ChildrenInfants

• Pertussis is transmitted to and from all age groups.

• Highly contagious,with 80% secondary attack rate among susceptible household contacts.

• Transmission of pertussis to household members has been documented.

• Young infants get pertussis primarily from family members, and are at high risk of morbidity and mortality.

• Adolescents get pertussis from household contacts and schoolmates.

• Adults get pertussis from work andhousehold contacts; parents (adult and adolescent) give pertussis to their infants.

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Reasons for Increased Pertussis Incidence• Increased reporting Improved recognition of cases in adults and

adolescents Reporting criteria changed in 1995

• Confirmation through PCR• Epidemiologic links

Serology

• Increasing incidence Waning protection from childhood vaccination

or prior infection Delay or refusal of vaccines

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Parental Refusal of Pertussis Vaccination is Associated With an Increased Risk of Pertussis Infection in ChildrenCase‐control study of Kaiser Permanente Colorado Health Plan 1996‐2007; each pertussis case matched to 4 randomly selected controlsFindings

• 156 lab confirmed pertussis cases; 595 matched controls• 18 (12%) pertussis vaccine refusers among cases; 3 (0.5%) among controls • Vaccine refusers had a 23‐fold increased risk for pertussis when compared with vaccine acceptors; 11% of all pertussis cases were attributed to parental vaccine refusal

Glanz JM et al. Pediatrics 2009;123:1446‐1451

Clinical Pearls regarding Pertussis Clinical Presentation and Lab Diagnostics (1)

• Afebrile with increasing cough duration and severity

• Coryza is associated with illness onset; does not become purulent as with most viral respiratory infections

• Paroxysmal cough‐ patient does not inhale until he has run out of breath ( possibly resulting in inspiratory “whoop”)

• Most infants will have close exposure to adolescent or adult with prolonged afebrile cough illness

• Cough in pertussis is not truly productive

• Sweating periods occur in adolescents and adults in between coughing episodes

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Clinical Pearls regarding Pertussis Clinical Presentation and Lab Diagnostics (2)

• PCR and culture are most useful in the first 3 weeks after illness onset

• Serology should not be used to diagnose pertussis in patients < 1 year after inoculation with acellular or whole‐cell vaccine formulation

• IgG anti‐PT ELISA is preferred to IgA anti‐PT testing ( IgA response following infection less common therefore potential for false negative result)

• Discourage use of DFA; discourage use of ELISA that uses whole B. pertussis as antigen

Diagnosis of Pertussis

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Diagnosis of Pertussis• Culture = “Gold standard"

3 – 7 days to complete Low sensitivity Lower positivity rates w/ prior immunization, increasing age, prior

antibiotics, improper collection of specimens

• PCR: 1 – 2 days to complete Remains positive longer More sensitive than culture Not standardized Pseudo-outbreaks due to single target PCR

• Serology Different tests used to measure serum antibodies Diagnosis depends on definition used Not standardized

AAP 2012 Red Book

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59

Antimicrobial Treatment and Prophylaxis for Adults

Primary agents Alternative agent

Azithromycin Erythromycin Clarithromycin TMP-SMX

500mg in a single dose on

day 1 then 250mg per day

on days 2-5

2g/d in 4 divided doses for 14 days

1g/d in 2 divided doses

for 7 days

TMP 320mg/d, SMX 1600mg/d in 2 divided doses

for 14 days

Pertussis Infection Control:Droplet Precautions

• Requires close contact (3ft)• Mask: worn in room• Gloves: If handle secretions• Do not need negative

pressure room

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Pertussis Vaccines

• Whole-cell DTP (1948): Suspension of Bp inactivated by heat & formaldehyde

Efficacy ~80%

Local and systemic adverse events (encephalopathy)

• Acellular vaccine (1996): Antigens extracted from B. pertussis organisms by

purification methods

Efficacy 63 – 89%; Tdap = 92%

Local and systemic side effects less common

Vaccine Alphabet Soup

• DTaP

• Tdap

• Td

Infant and children

Adolescents & adults

Adult booster (former?)

Tetanus component

Diphtheria component

Pertussis component

Size of letter denotes size of dose

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Vaccine Indications

• DTaP: All children at 2, 4, & 6 months Booster at 15-18 months & age 4-6 years

• Tdap: Adolescents aged 11-18 yrs (11-12yrs preferred) All adults age 19-64 yrs if last Td ≥ 10 yrs ago Pregnant women in each pregnancy (27- 36 wks) Adults 65+ if infant contact Give <10 yrs since Td: if risk for pertussis

exposure, close contacts of infants Includes wound management

Hospital-based Outbreaks of Pertussis• Texas, 2004 (MMWR 2008;57:600)

11 newborns at a hospital develop pertussis after exposure to a nurse with the disease

• Washington, 2004 (ICHE 2007;28:537) 10 cases of pertussis among hospital staff, community

contacts; index cases were ED MD and RT• Kentucky, 2003 (ICHE 2006; 27:541) Pertussis in a 2 mth old preemie traced to a nurse in

intermediate care nursery 72 infant patients and 72 HCWs given prophylaxis

• Pennsylvania, 2003 (CID 2006;42:981) 17 symptomatic cases of pertussis among HCPs after 1

day exposure to infant with pertussis

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ACIP Recommendations for Use of Tdap in Health-care Personnel (HCP)

• HCP with direct patient contact in hospitals or ambulatory care settings should receive a single dose of Tdap as soon as feasible Priority for HCP with direct contact with infants Interval as short as 2 years since last Td is

recommended

• Other HCP should receive Tdap according to routine recommendations; interval as short as 2 years since last Td is encouraged

• Hospitals and ambulatory care facilities should provide Tdap for HCP and use approaches that maximize vaccination rates; education, convenience, no charge

Reference:1. CDC. MMWR. 2006;55(RR-17):1-44.

Outbreaks in Healthcare FacilitiesSetting Index Case Staff

CasesPatient Cases

Diagnostic Method Reference

Acute care hospital Infant, HCW 5 2 Culture, serology Kurt 1972

Pediatric hospital Infant, HCW 13 17 Culture Linnemann 1975

Acute care hospital Visitor (Mother) 5 2 Symptoms, serology, DFA Valenti 1980

Residential facility - - - Serology, culture Fisher 1989

Residential facility HCW 42 107 ELISA, DFA, culture Steketee 1988

Extended care Patient 8 38 ELISA Addis 1991

Residential facility HCW 6 41 Serology, culture Tanaka 1991

Acute care hospital Infant 5 10 - Shefer 1995

Pediatric hospital HCW 87 1 DFA, culture Christie 1995

Pediatric hospital Infant 1 3 Culture Nouvellon 1999

Pediatric ED HCW 10 - Serology, culture, link Gehanno 1999

Acute care hospital Infant, HCW ? - DFA, serology Martinez 2001

Hospital Nursery Visitor (Mother) 1 3 ELISA, culture, PCR Spearing 2002

Acute care hospital HCW 15 2 ELISA, PCR Bassinet 2004

Nursery, NICU HCW 4 1 PCR, Serology, Culture MMWR 2005

Pediatric unit Infant 17 2 Culture, PCR, link MMWR 2005

Pediatric unit HCW 4 2 Culture, PCR, Serology MMWR 2005

Heme-Onc unit HCW 10 0 PCR Boulay 2006

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Outbreaks in Healthcare FacilitiesSetting Index Case Staff

CasesPatient Cases

Diagnostic Method Reference

Acute care hospital Infant, HCW 5 2 Culture, serology Kurt 1972

Pediatric hospital Infant, HCW 13 17 Culture Linnemann 1975

Acute care hospital Visitor (Mother) 5 2 Symptoms, serology, DFA Valenti 1980

Residential facility - - - Serology, culture Fisher 1989

Residential facility HCW 42 107 ELISA, DFA, culture Steketee 1988

Extended care Patient 8 38 ELISA Addis 1991

Residential facility HCW 6 41 Serology, culture Tanaka 1991

Acute care hospital Infant 5 10 - Shefer 1995

Pediatric hospital HCW 87 1 DFA, culture Christie 1995

Pediatric hospital Infant 1 3 Culture Nouvellon 1999

Pediatric ED HCW 10 - Serology, culture, link Gehanno 1999

Acute care hospital Infant, HCW ? - DFA, serology Martinez 2001

Hospital Nursery Visitor (Mother) 1 3 ELISA, culture, PCR Spearing 2002

Acute care hospital HCW 15 2 ELISA, PCR Bassinet 2004

Nursery, NICU HCW 4 1 PCR, Serology, Culture MMWR 2005

Pediatric unit Infant 17 2 Culture, PCR, link MMWR 2005

Pediatric unit HCW 4 2 Culture, PCR, Serology MMWR 2005

Heme-Onc unit HCW 10 0 PCR Boulay 2006

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Pertussis in Healthcare Workers• Waning immunity

• Regular contact with infected patients Risk of infection 1.7- fold greater than general pop.

• Annual incidence of infection 2 – 8%

• Cost of outbreaks reported as $44–75K

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HCW Exposures to Pertussis

• Large quaternary pediatric care network

• Jan 1, 2002‐July 18, 2011

• 1193 confirmed HCW pertussis exposures

• 219 index cases

• 38.8% infants < 6 months of age

• 7 were HCWs ( 3.2%)

• 77.5% occurred in ED or ambulatory care site

Kuncio DE et al. Pediatrics 2014;133:15‐21.

HA Pertussis Outbreak- Arizona, 2011

• Index case: 4 week old female, 28 wk gestation• Admitted for apnea felt to be secondary to GE reflux

• Cough lasted 26 days, no isolation; sick sibling visited

• Pertussis identified upon transfer to another hospital; initial hospital had 10 HCPs who worked during cough illness

• 15 pertussis cases among 5 infants and 10 HCP in NICU

• Cost to hospital $97,745

Yasmin S et al. JPIDS 2014;3:81‐4.

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Pertussis Post-Exposure Prophylaxis

• Give antibiotics to close contacts and to persons at high risk for having severe pertussis

• Close contact of a symptomatic patient with pertussis Face-to-face exposure within 3 feet Direct contact with respiratory, oral, or nasal secretions Share a confined space in close proximity for ≥ 1 hour

• Persons at high risk for having severe disease Infants < 1 year of age Immunocompromised persons Persons with underlying medical conditions (e.g., chronic

lung disease, CF)

PEP for Vaccinated HCWs

NEW (2011):

April 2012:Vaccinated HCP still need PEP CID 2012;54(7):938–45Conclusions. Using the predefined definition of pertussis infection, noninferiority for preventing pertussis following exposure was not demonstrated for daily symptom monitoring of Tdap-vaccinated HCP without PEP when compared with antibiotic PEP. However, the small number of exposed HCP warrants further study of this approach.

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Tuberculosis

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Why Worry About TB?• Prevalence: 13.7 million people• Annual Incidence: 9.2 million• ~ 1.3 million deaths per year

TB: Clinical Syndromes

• Latent: Infected but progression halted

• Disease: Primary: Initial infection

progresses

Reactivation:• Pulmonary

• Extrapulmonary

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Latent TB Infection (LTBI) Pulmonary TB Disease

Inactive, contained tubercle bacilli in the body

Active, multiplying tubercle bacilli in the body

TST or blood test results usually positive

TST or blood test results usually positive

Chest x-ray usually normal Chest x-ray usually abnormal

Sputum smears and cultures negative

Sputum smears and cultures may be positive

No symptoms Symptoms such as cough, fever,

weight loss

Not infectious Often infectious before treatment

Primary Tuberculosis

Gohn Complex~ 90% do not disseminate

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Primary:• Traditionally

disease of childhood

• Now increasingly in adults

• Progressive 5%– Children

(meningitis, GI, bone)

– Adults (pulmonary)

Reactivation:•Long delay

•Change in T-cell immunity

•Cavitary - high inoculum

~ 5% of Primary Cases in Children Disseminate w/i 5 yrs.

Meningitis

GI

Bone & Joint

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Cavitary TB (Progressive Primary, Reactivation)

http://www.drgreene.com/imagepage/1607.asp

~ 5% of Primary Cases Reactivate many years later

http://medstat.med.utah.edu/WebPath/INFLHTML/INFL053.html

Confluent granulomas in a case of pulmonary tuberculosis leading to

cavitation.

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TB in Children usually acquired from an Adult

• Jacob Age 2 ½

• One year of progressive deformity and reluctance to walk. No fevers.

• Physical findings marked kyphosis, weakness of left leg

• Mother"asymptomatic”– equivocal CXR– smear +

• MRI

Diagnosis

• Culture

• PCR

• Tissue biopsy

• Empiric

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Pulmonary* TB: Infection Control

• Early suspicion

• Airborne precautions N95 respirator/PAPR

• Negative pressure rooms

*Also laryngeal TB

AIR

FL

OW

AIRFLOW

Screening of HCWs

• Tuberculin skin testing: Positive based on comorbidities

Most HCWs: 10mm +

2-step test upon hire

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Screening of HCWs

• INF- assays Measure WBC release of INF- when mixed

with M. tuberculosis antigens

No booster phenomenon

Not affected by BCG vaccination

Does not require second visit

Challenges with indeterminate results

Exposures

• Concentric ring approach Those at highest

risk/longest contact tested first

• Think adult contact for pediatric TB case

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Take Home Messages• Respiratory viruses, pertussis, TB = cause of

healthcare-associated infections• Prevention methods involves source

identification and control, use of isolation and PPE, and pharmacologic strategies

• Get your influenza vaccination every year

no relevant disclosures - johns hopkins hospital · 07/03/2014 2 objectives • discuss...

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