RNA virus
Virus family associated with St Louise encephalitis, Japanese encephalitis, Murray Vallen enceph, and Kunjin enceph
2 lineage of<unk> V - only lineage 1 associated with human disease originating in Middle East/Israel
Bird- mosquito- bird cycle
Passerine birds are amplification host
Starts in spring, ends in fall when mosquitos dormant
Culex mosquitos
Unclear if human infection from culex bite or other bridge vector mosquito species
House sparrows have high level of viremia and are amplifiers
Humans and horses also but viremia is low so are not important amplifiers<unk> V in birds feces and oral secretions
Bird to bird transmission possible in lab
Birds can be infected by eating infected mosquitoes, birds or odents but importance of oral spread in nature unclear
Found in Africa, Middle East, Russia, Australia
First appeared in eastern US in 1999 but now found nationwide
Most human infections occur in August and Sept but can happen from May to Dec
Human Transmission
Most from mosquito bites
Maternal fetal
Breast milk
Blood transfusion
Percutaneous lab infection
Most from mosquito bites
Maternal fetal
Breast milk
Blood transfusion
Percutaneous lab infection
West Nile virus
Meningitis
Zika virus
SAH
Heartland virus
Lyme disease
Hantavirus
Brain abscess