Arbovirus Flashcards
Arbovirus includes
Arthropod borne viruses
Bunyavirus
Togavirus
Flavivirus
Reoviridae
Rhabdoviridae
Togavirus is known to cause
TONGA CAR
Rubella virus
Chikungunya virus
Eastern equine encephalitis
Western equine encephalitis
Flavivirus is known to cause
Japanese encephalitis
Yellow fever
Zika
Dengue
West Nile fever
Reoviridae is known to cause
Colarado tick fever
Rhabdoviridae known to cause which disease (Arbovirus)
Vesicular stomatitis vurus (Sandfly)
Bunyaviridiae family is segmented or non segmented
Segmented - 3 segments
Bunyaviridiae family includes
Bunyavirus
Phlebovirus
Nairovirus
Hantavirus
Bunyavirus is known to cause and vector
California encephalitis - encephalitis
Aedes
ABCDE
Phlebovirus is known to cause and vectors
Sandfly fever - Sandfly
Rift valley fever - Aedes
Fever, Rhinitis, encephalitis
Nairovirus is known to cause and vector
Crimian congo hemorrhagic fever
Hard tick
Animal to human or human to human
Hantavirus is known to cause and associated with
Hantan Renal syndrome - Interstitial Nephritis
Hanta pulmonary syndrome - Interestital pneumonia
Associated with Hemorrhages and rodents
Vector of Eastern equine encephalitis
Aedes - 50 to 70% mortality
Vector of Western equine encephalitis
Culex
Incubation period of Dengue and Chikungunya
5-6 days
Incubation period or Japanese encephalitis and Yellow fever
JE - 5 to 15 days
Yellow fever - 3 to 6 days
Incubation period of Kyasanur forest disease
4-8 days
Vector of Chikungunya virus
Aedes
Clinical features seen in Chikungunya
Fever - Saddleback fever (Biphasic)
Migratory arthritis
+ Arthralgia (small joints)
Lymphadenopathy
Which sign is seen in Chikungunya virus
Chick sign - Post chikungunya Hyperpigmentation
Diagnosis of Chikungunya virus
Antibody - IgM in 4 days, upto 2 months (MAC-ELISA)
IgG in 2 weeks to years
RT PCR
Rubella virus is now part of which family
Matonaviridae
Rubella virus AKA
German measles or three day measles
Mode of transmission of Rubella virus
Respiratory droplets
Transplacental
Incubation period for Rubella infection
14 days
Clinical features of Rubella infection
URTI
Post auricular Lymphadenopathy
Rash - last for 3 days, very similar ro Measles
Spots in Rubella infection
Forscheimers spots - seen on palate
Non specific for Rubella
Clinical features of Congenital Rubella syndrome
Most dangerous trimester - 1st
Baby excrete rubella virus in urine, saliva
PYAR MEIN ANDHA BEHRA
Patent ductus arteriosus
SNHL
Cataract
Blueberry muffin baby
Diagnosis of Rubella virus
Cell lines
No Cytopathic effect
Antigen
Antibody
RT PCR
Diagnosis of Rubella in Pregnant lady
IgM indicates Acute/current infection
IgG > 1:8 - past infection
Rubella vaccine, Strain and it’s Contraindications
Live attenuated vaccine - C/I in Immunocompromised individual
Strain - RAV27/3
Vector and their species for Japanese encephalitis virus
Culex - C. Tritaeniorhyncus - M/C in world
C. Vishnui - M/C in India
Reservoir, amplifier and dead end hosts in case of Japanese encephalitis
Reservoir - ardied birds (Crane)
Amplifier - Pigs
Dead end hosts - Humans and animals
Clinical features of Japanese encephalitis virus
Prodromal symptoms (mild)
Acute encephalitis
Long term neurological deficit
Lab diagnosis and sample for Diagnosis of Japanese encephalitis virus
RT PCR (CSF)
Vaccine Prophylaxis in case of Japanese encephalitis virus
Live attenuated
Inactivated vaccine
Live attenuated vaccine for Japanese encephalitis virus
SA 14-14-2 vaccine (M/c used in India)
Strains of Inactivated vaccine for Japanese encephalitis virus
Nakayama and Beijing P1 strain (mouse Brain derived and formalin inactivated)
Beijing P3 strain (cell line derived)
Yellow fever genotypes, serotypes and endemic in
Genotypes 7
Serotype 1
Endemic in west africa and south America
Vector of yellow fever
Aedes Aegypti
Cycles of Yellow fever
Jungle cycle - Monkeys and forest mosquitos
Urban cycle - Humans and urban mosquito
Mild and severe clinical features of Yellow fever
Mild - Fever with Bradycardia (Fagets sign), Myalgia
Severe - Hemorrhagic manifestations (platelet dysfunction)
Hepatitis - Midzonal necrosis
Unvaccinated traveler from yellow fever endemic zone to india need to
Quarantine for 6 days
Aedes aegypti index should be maintained around airports, seaports
Less than 1
Serology findings of Yellow fever
Serology - IgM (3 days of onset), Ig
Cytopathic effects seen in Yellow fever
Liver - Midzonal necrosis
Body - Torres body
Vaccine used for Yellow fever, Route and it’s Efficacy
Yellow fever 17D vaccine - live attenuated
Prepared from allantoic cavity
Route - s/c, single dose
Efficacy -;7 days to 35 years
Contraindications of Yellow fever 17D vaccine
Less than 9 months
Pregnancy
HIV/Immunodeficiency
Egg allergy
Cholera and yellow fever vaccine can interacts together - there should be gap of 3 weeks
Vector, host of Monkey fever/Kyasanur forest disease
Hard tick
Host - Monkey (Amplifier host)
Clinical features of Monkey fever/Kyasanur forest disease
Fever, Myalgia
Mucosal and cutaneous hemorrhages
Season of Monkey fever
January - June
Vector of Zika flavivirus
Aedes
Transmission of Zika virus
Vector borne
Transplacental
Blood transfusion
Sexual transmission
In case of mother to child transmission Zika virus deposits into
Hoffbeaur cells of placenta (Macrophages)
Clinical features of Congenital Zika virus infection
Eyes - Optic neuropathy, Congenital glaucoma
Brain - Microcephaly, Ventriculomegaly
Clinical features seen in adults in case of Zika virus infection
Myalgia, Arthralgia, Rash
CVS involvement
CNS - Gullian barre Syndrome
Diagnosis of Zika virus
RT PCR (Blood, urine)
IgM - Plaque reduction neutralisation test for confirmation of antibody
Most common mosquito borne infection and most rapidly spreading infection
Dengue
Most common Arbovirus found in India
Dengue virus
Serotypes of Dengue virus and which one is most dangerous
DEN 1 - DEN 4
Most dangerous - DEN 2
Recently new serotype of Dengue is found in
DEN - 5 in Bangkok
Antibodies dependent enhancement (ADE) means
Primary Dengue infection - secondary dengue infection (more severe) - because Antibody produced against 1st serotype will combine and protect 2nd serotype from immune system)
Clinical forms of Dengue
Dengue fever
Dengue hemorrhagic fever
Dengue shock syndrome
Dengue fever clinical features
High fever (breakbone/saddleback fever)
Maculopapular rash - chest then upper limbs
Frontal headache
Muscle and joint pains
Dengue hemorrhagic fever Clinical features
Dengue fever +
Platelet count <1 lac
Platelet functional qualitative defects
Positive torniquet test (>20 spots/inch)
HCT rises by 20% (Hemoconcentration evidence)
Dengue shock Syndrome
Endothelial damage
Dengue Hemorrhagic fever +
Shock
WHO Grading Dengue fever
Fever with 2 or more following features - Headache, Retroorbital pain, Myalgia, Arthralgia
Leukopenia, Thrombocytopenia (<1 lac), No evidence of plasma loss
WHO Grade 1 Dengue
Dengue Hemorrhagic fever
Dengue fever + Torniquet sign +ve
Thrombocytopenia, HCT Rises (>20%)
WHO grade 2 of Dengue
Grade 1 features + spontaneous bleeding
WHO Grade 3 of Dengue
Grade 2 + Circulatory failure (weak pulse , hypotension, Restlessness)
WHO grade 4 of Dengue
Dengue Shock Syndrome
Profound shock with undetectable BP and pulse
Lab diagnosis methods of Dengue
PCR - Day 1 to 7
NS1 Antigen - +ve upto day 7
IgM -MAC ELISA - from day 7
Treatment of Dengue
Supportive treatment
Platelets transfusion (single donor apheresis platelets)
Fluids
Vaccine for Dengue
Dengraxia - gives protection against all 4 serotypes (D1 to D4)
Aedes mosquito features
Aedes aegypti, Aedes albopictus
Tiger mosquito
Day time biters
Peak - Dawn and dusk
Cigar shaped eggs
Transovarial transmission in mosquito
Diseases transmitted by Aedes as a vector
AEDEEZ CCRYD
EE - Eastern equine encephalitis
Z - Zika virus
C - California encephalitis
C - Chikungunya
R - Rift valley fever
Y - Yellow fever
D - Dengue fever
