West Nile Virus Infections Virus Vector Epidemiology Clinical Diagnosis Treatment Tenth National Conference on West Nile Virus in the United States http://www.cdc.gov/ncidod/dvbid/westnile/conf/February_2009.htm

West Nile Virus Infections Virus Flavivirus – flavi = yellow (latin) yellow fever Family = Flaviviridae – single-stranded RNA viruses Arbovirus – arthropod-borne Flavivirus

Hepacivirus Pestivirus

Yellow Fever, West Nile, Dengue, Tick-borne Encephalitis Virus, Japanese B Encephalitis Virus, St. Louis Encephalitis Virus, etc. Hepatitis C Classical Swine Fever Virus, etc

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West Nile Virus Infections Vector - mosquito Culex

http://kaweahoaks.com/html/mosquito.html

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http://www.cdc.gov/NCIDOD/DVBID/WESTNILE/conf/pdf/p1-reiter.pdf

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http://www.vetmed.ucdavis.edu/ucmrp/images/breedingsites.jpg

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http://www.fairfaxcounty.gov/hd/westnile/images/wheelbarrow.jpg

http://images.jiunlimited.com/thw/thw13/PH/px5323_20030818_46/px5323_20030818_46_01/28502937.thj.jpg?5323_030818_78960

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West Nile Virus Infections Epidemiology Incubation Period 2-14d Vector - mosquito Transplanted - 4 in 2002 Blood - few Breastmilk - 1 probable Transplacental (mother to child) Occupational – 2 (2002)

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Sentinel Chickens Cats & Dogs ~30% mortality

WEST NILE VIRUS: Epidemiology Report, LA County Cumulative Totals — December 4, 2008

http://lapublichealth.org/acd/docs/West%20Nile/wnv%20epi%20totals%202008%2012.4.08.pdf

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West Nile Virus Infections Clinical Febrile Illness 1/5 CNS (Severe) 1/150 Meningitis About 25% to 35% of people with neuroinvasive WNV infection reportedly have meningitis without evidence of encephalitis.

Encephalitis About 60% to 75% of people with neuroinvasive WNV infection reportedly have encephalitis or meningoencephalitis, which is characterized by altered mental status of focal neurologic findings. (http://www.cdc.gov/ncidod/dvbid/westnile/clinicians/clindesc.htm#severedisease)

WNV Human Infection “Iceberg”