West Nile Virus
Timeline 1937 First Case reported 1950 Virus studied in Egypt 1957 Outbreak in Israel 1960 Equine cases 1999 Appeared in US
World Wide Africa West Asia Eastern Europe Middle East United States
New York 1999 62 Human cases 7 deaths 2000 21 Human cases 2 deaths Numerous bird (crow) causes
Positive States Connecticut Indiana Ohio Maryland Pennsylvania Florida Virginia Massachusetts New Hampshire New Jersey New York Rhode Island Georgia
Transmission of WNV Birds are reservoirs Mosquitoes are Vectors Humans and horses are incidental hosts No horizontal spread of WNV from humans to horses
Bird Mosquito Horses Humans
Mild Infection Symptoms Symptoms occur abut 5-15 days after mosquito bites Mild fever Headache Body aches Rash Swollen lymph nodes
Serious Infection Symptoms Seen mostly in elderly Less than 1% of infected develop into severe illness Causes encephalitis (inflammation of the brain) Rapid onset of severe headache High fever Stiff neck Confusion Coma Muscle weakness
Diagnosis Testing Done if person develops symptoms Medical history first assessed People who live in or have traveled to areas where WNV has been identified are at high risk People over 50 are at high risk
Diagnosis Blood Sample Drawn and taken to commercial or public health laboratory for conformation IgM antibodies tested in serum or cerebral spinal fluid ELISA test Used to incubate goat IgM and human serum and test it with WNV antigen from vero cells infected from gulls mice and goats
Treatment No treatment Can treat secondary symptoms with fluids Need to seek medical attention immediately Doctor Veterinarian
Prevention Eliminate outdoor activities between dusk and dawn Wear protective clothing Use mosquito repellant Keep pools treated Empty and clean birdbaths, plant trays once a week
Prevention Replace outdoor lights with yellow lights Report dead birds to proper authority Vaccinate horses against WNV Make sure screens are bug tight