new viral encephalitis viral hemorrhagic feverkau.edu.sa/files/0004258/subjects/arboviruses.pdf ·...
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Viral Encephalitis
Viral Hemorrhagic Fever
Viral Zoonosis
Rift Valley Fever
In Saudi Arabia and Yemen –2000
غبس عجذ اللطف جوجىم. د
ملخ الطت والعلىم الطجخ
جبهعخ الولل عجذ العشش ثجذح
(م2000-10)هـ 7-1421
Yellow Fever
Dengue Fever
Ebola
Arboviruses
( Arthropod-Borne Viruses )
- Mosquitoes,
- ticks,
- sandflies
Examples of Arthropod Vectors
Aedes AegytiAssorted Ticks
Phlebotmine SandflyCulex Mosquito
Viral Encephalitis
Viral Hemorrhagic Fever
• Other viral Syndromes(Arthralgia, Rash, Pulmonary Syndromes,
etc.)
Arboviruses
• more than 400 isolated
• ~ 100 human pathogens
Arboviruses
Members of the Following Families :
• Togaviruses (genus Alphaviruses)
• Flaviviruses
• Bunyaviruses
• Reoviruses (genus Orbiviruses)
Additional Hemorrhagic Fever
Viruses :
• Arenaviruses
• Filoviruses
Zoonotic Viral Infections Not Transmitted
by Arthropods (Direct Contact with
Animals, person-to-person, nosocomial,
etc.)
Arboviruses
Members of the Following Families :
• Togaviruses (genus Alphaviruses)
• Flaviviruses
• Bunyaviruses
• Reoviruses (genus Orbiviruses)
Note :
Rubella virus belongs to the
• Togaviruses (genus Rubivirus)
but is not transmitted by insects
• What does Rubella virus cause?
• How is it transmitted?
• Rift Valley Fever
Arboviruses
• 1902 Walter Reed discovered
the cause of yellow fever, the
first human virus to be
described. He proved mosquito
transmission
Yellow fever :
• One of the great plagues of
mankind.
• Epidemics in the 17th, 18th, 19th,
and 20th century
• 1937 Theiler developed the
17D vaccine (live-attenuated)
Objectives
1. Recognize that viruses cause major outbreaks of encephalitis and hemorrhagic fevers or other dangerous syndromes
Objectives
1. (cont)
and that some of these infections (e.g. yellow fever played an important role in the history of mankind)
Objectives
3. Recognize that many viral infections have animal reservoirs (e.g. Birds, mammals, rodents, etc)
Objectives
4. List the major arboviral infections that have been reported in Saudi Arabia
Objectives
5. Recognize the possibility of nosocomial transmission or direct transmission of some dangerous viral infections
Objectives
6. Recognize situations in which vaccination against some arboviral infections is indicated
Objectives
7. Describe means of control
of some arboviral or
non-arboviral exotic
infections
Objectives
2. List the names of at least five viral illnesses transmitted by arthropods
Viral Encephalitis
Viral Encephalitis
Natural cycle Human Infection
Wild Bird Man
Mosquito Mosquito Mosquito Mosquito
Wild Bird Man SLE
Domestic Birds, man deadend
Mammals horse WEE, EEE
Viral Encephalitis
Natural cycle Human Infection
Wild Bird Man
Mosquito Mosquito Mosquito Mosquito
Wild Bird Man SLE
Domestic Birds, man deadend
Mammals horse WEE, EEE
Arboviruses
Members of the Following Families :
• Togaviruses (genus Alphaviruses)
• Flaviviruses
• Bunyaviruses
• Reoviruses (genus Orbiviruses)
Flavivruses
• Includes 69 viruses:
67 are arthropod borne (mosquitoes, ticks)
• includes pestiviruses and hepatitis C virus
• includes the most important arboviral
diseases of man : Yellow fever,
Japanese Encephalitis,
Dengue
West Nile Virus Comes to New York
Ghazi A. Jamjoom
West Nile Virus
West Nile-New York, August 99
• 60 patients sick
• 7 died
• first appearance of virus in U.S.
• Extensive spraying with insecticide
West Nile – USA 2003
• 4007 hospitalized cases (estimated 100000
cases
• 263 deaths
• 40 States
Patients
• Mostly elderly
• Disease : Encephalitis
Definitive Studies :
Virus is the West Nile Virus, for the first
time coming to North America
West Nile Virus USA:
Genomic Relationships
• Whole genome is 99% identical to a West
Nile strain isolated in Israel in 1998, and a
strain found earlier in Egypt, suggesting
origin from Middle East
West Nile Virus : Zoonotic Infection
• Natural reservoir : Birds
• Vector : Mosquitoes (e.g. Culex, Aedes,
Anopheles, etc, ticks)
• Some birds may die from infection
(e.g. crows, other birds at N.Y.zoo ,e.g. one
bald eagle)
• May cause encephalitis in horses
How did it reach New York ?
• Travel by infected humans
• Illegal importation of birds or other pets
• By virus-infected ticks or mosquitoes
West Nile Virus
Comes to New York
West Nile Virus : Classification
• Family : Flaviviruses
• Antigenic Complex :
Japanese Encephalitis :
JE (Japanese encephalitis)
MVE (Murray valley encephalitis (Australia)
SLE (St. Louis encephalitis)
WN (West Nile)
Kun (Kunjin (Australia)
• Distant relatives : Yellow Fever, Dengue, Tick-borne encephalitis
complex
Flavivruses : antigenic relationships
• Dengue Virus Group DEN 3
DEN 1
DEN 2
DEN 4
• Japanese Encephalitis Group
WN
KUN
MVE
JE
SLE
• Yellow FeverYF
• Tick-Borne EncephalitisPow
LGT
LI
TBE
Flavivruses : Disease Patterns
• Flaviviruses associated primarily with the encephalitis
syndrome :
St. Louis Encephalitis (SLE) Japanese Encephalitis (JE)
Murray Valley Enceph. (MV) Tick-borne Encephalitis (TBE)
• Flaviviruses associated primarily with fever, arthralgia,
and rash:
Dengue Fever, West Nile Fever, Other Viruses
• Flaviviruses associated primarily with hemorrhagic
fever:
Yellow Fever, Dengue Hemorrhagic Fever, Others
Arboviruses
Members of the Following Families :
• Togaviruses (genus Alphaviruses)
• Flaviviruses
• Bunyaviruses
• Reoviruses (genus Orbiviruses)
Bunyaviruses
California Encephalitis:
• most serious Bunyavirus disease
in USA
• Vector : Aedes
• Amplifying hosts: chipmunks,
squirrels
Viral Hemorrhagic Fever
Hepatitis Arthralgia hemorrhageYF CHIK Dengue
CCHF O’nyong YF
Dengue CCHF
RVF
Fever
Shock EncephalitisDengue EEE
YF WEE
CCHF JE
RVF SLE
Renal FailureHantaan
Arboviruses
Members of the Following Families :
• Togaviruses (genus Alphaviruses)
• Flaviviruses
• Bunyaviruses
• Reoviruses (genus Orbiviruses)
Flavivruses : antigenic relationships
• Dengue Virus Group DEN 3
DEN 1
DEN 2
DEN 4
• Japanese Encephalitis Group
WN
KUN
MVE
JE
SLE
• Yellow FeverYF
• Tick-Borne EncephalitisPow
LGT
LI
TBE
Distribution of Dengue
Arboviruses
Members of the Following Families :
• Togaviruses (genus Alphaviruses)
• Flaviviruses
• Bunyaviruses
• Reoviruses (genus Orbiviruses)
Bunyaviruses
• Crimean-Congo virus
• Rift Valley Fever virus
• Hantavirus
• Rift Valley Fever
(املتصدع)محى وادي الصدع م 2000 -العربية السعودية واليمن يف اململكة
Rift Valley Fever
In Saudi Arabia and Yemen –2000
غبس عجذ اللطف جوجىم. د
ملخ الطت والعلىم الطجخ
جبهعخ الولل عجذ العشش ثجذح
(م2000-10)هـ 7-1421
تبرخ المرض ف إفرقب
1930مب •
1950جىة افزقب •
هعظن االوثئخ ف شزق وجىة افزقب حت عبم •1977
1977الىثبء صل هصز عبم •
1987الىثبء صل السغبل وهىرتبب عبم •
1993وثبء آخز ف هصز عبم •
مب، الصىهبل ، )الىثبء تفش ف شزق افزقب•1998-3إل 1997-10تبشاب ، واثىثب هي
المرض ف إفرقب تواجدمىاطه
القربة والت كبيرة أمبكه األوبئة الاستمر فهب تىطه المرض ف إفرقب
وببء شرق افرقب 19998-1997ف
شخص ف مب ، عذح هئبد ف الصىهبل، 300وفبح •وآالف الحىابد ف الجلذي
هي FAOتحذز هظوخ األغذخ والشراعخ •
أى الىثبء قذ عجز الجحز األحوز إل الجشزح العزثخ لهذد الوبشخ والبص هبك
الوظوخ تزفع حظزهب عي دول القزى األفزق عبم •وتشاذ ( ظهىر الجفبف)لتغز األحىال الجىخ 1999
الوبعخ لذي الوبشخ
محى وادي الصدع العربية السعودية يف اململكة
م 2000 - Rift Valley Fever
In Saudi Arabia –2000
كف جبء المرض
•
•
•
مه أه جبء المرض ؟
•
RNA Sequence
لمبرا ف مىطقة جسان ؟
•
•
•
•
لمبرا أغلب الحبالت ف جسان(ثم عسر )
•
•
Theالفروش
Virus
• Family : Bunyaviruses
• Group : Phlebovirus
• Negative –stranded RNA
trisegmented genome
(3 circular segments)
Bunyaviridae(over 300 virueses)
Genera :
• Bunyavirus (Bunyamwera, Calif. Enceph, LaCross
• Hantavirus (Hantaan)
• Nairovirus (Crimean Congo)
• Phlebovirus (Sandfly fever Naples, Toscana, Rift
Valley, Sandfly fever Sicilian)
• Tospovirus (Tomato Spotted Wilt (Plants)
Mosquitos
• Culex tritaeniorrhynchus
• Aedes caspius
Mosquitos
• Culex tritaeniorrhynchus : vector
• Aedes caspius : vector
reservoir
(between epidemics)
Sheep and Goats
• More than 90% had antibody to RVF
( Al – Ardah district )
Control Measures -1
• Intensive mosquito-control program;
• Restriction of movement of domestic animals;
• Comprehensive educational campaign to eliminate contact with sick animals and mosquitoes (including provision of free permethrin-impregnated bednets);
Insecticide-Impregnated Bednets
for Protection fromMosquitoes
طرق اوتقبل العذوي
•
•
•
•
Aerosol Trasmission
البعىض الىبقل للعذوي
•
Aedes, Culex, Anopheles
•Aedes
Transovarial Transmission
•
•Ticks
Mosquitoes control
• Bed nets:
Animal control
Control of animal movement.
Vaccination.
Live attenuated.
Killed vaccine.
Elimination.
Vaccinesاللقبح
• Formalin-Inactivated vaccines
- Animals
- Veterenarians, Lab Workers
• Live-Attenuated Vaccine (MP-12)
( experimental)
Human Infection Control
• Treatment
Ribavirin – under evaluation
• Vaccination (for veterinarians, lab workers,
other exposed people)
• Protection ( Window screens, bednets,
repellants )
هل تىتقل العذوي مه شخص خر ؟
•
Hospital Cross Infection
•
إل مت ستمر وجىد المرض ؟
•
•
•
Human Infection
• Asymptomatic
• Self-limited febrile illness
• Complications :
Retinitis 15%
Hemorrhagic fever 1%
Encephalitis 1%
التشخص المخبر
Laboratory Diagnosis
• Detection of viral antigen (ELISA)
• Detection of patient Ab (ELISA –IgM)
• Detection of viral RNA with PCR
• Virus Isolation in cell culture (e.g
vero) and confirmation by IF stain
• Immunoperoxidase staining of viral antigens in sections of the liver
العالج
•
Ribavirin
احتبطبت السالمة الالزمة للتعبمل مع العىبت المصببة
وعسل الفروش
•
•( Biosafety level 3 Laboratory )
Hantaviruses
• Forms a separate genus in the
Bunyavirus family.
• Unlike under bunyaviridae, its
transmission does not involve an
arthropod vector.
• Enveloped ssRNA virus.
• Virions 98nm in diameter with a
characteristic square grid-like
structure.
• Genome consists of three RNA
segments: L, M, and S.
Rodent Carriers of Hantaviruses
Stripped field mouse (Apodemus agrarius)
Bank vole (Clethrionomys glareolus)
Deer Mouse (Peromyscus maniculatus) Rat (Rattus)
Hantavirus Pulmonary Syndrome (HPS)
• More than 250 cases of HPS have been reported throughout North
and South America with a mortality rate of 50%
• In common with classical HVD, HPS has a similar febrile phase.
• However, the damage to the capillaries occur predominantly in the
lungs rather than the kidney.
• Shock and cardiac complications may lead to death.
• The majority of HPS cases are caused by the Sin Nombre virus.
The other cases are associated with a variety of other hantaviruses
e.g. New York and Black Creek Canal viruses.
Additional Hemorrhagic Fever
Viruses :
• Arenaviruses
• Filoviruses
Zoonotic Viral Infections Not Transmitted
by Arthropods (Direct Contact with
Animals, person-to-person, nosocomial,
etc.)
Lassa Fever
Found predominantly in West Africa, in
particular Nigeria, Sierra Leone and
Liberia.
The natural reservoir is multimammate rat
(Mastomys)
Man may get infected through contact with
infected urine and faeces.
Man to man transmission can occur
through infected bodily fluids and Lassa
fever had caused well-documented
nosocomial outbreaks.
Mastomys