West Umatilla Mosquito Control District
DISEASE SURVEILLANCE: MOSQUITO POOLS

What is a mosquito pool?

mosquito poolDuring the mosquito season we collect adult mosquito pools to test for mosquito borne diseases. A mosquito pool is a collection of mosquitoes (usually about 50) of any given species or group (i.e. Culex mosquitoes) that are likely to carry/transmit a virus. Since stagnant water Culex mosquitoes are the primary mosquitoes implicated in transmission of West Nile Virus (WNV), and Saint Louis Encephalitis (SLE) , and Western Equine Encephalitis (WEE) they are this species is targeted for testing.

What is the VecTest?

The VecTest is a WNV/SLE/WEE antigen panel assay designed by Medical Analysis Systems, Inc. Basically, it's a rapid detection dipstick test for West Nile Virus (WNV) , Saint Louis Encephalitis (SLE), and Western Equine Encephalitis (WEE). Mosquitoes are ground up in a special solution and then wicked up on to a test strip. The antigen for WNV/SLE, if present, binds to specific antibody on the test strip producing a reddish color change indicating the presence of viral antigen in the sample. The assay doesn't measure the quantity of viral antigen in a sample only the presence of it.

By keeping track of positive VecTest mosquito pools we will be able to better monitor the distribution of these viruses in the District. A positive mosquito pool means that local mosquitoes are infected with the virus and possibly capable of transmitting it to other hosts. By combining this information with bird surveillance records, horse and human viral infection data, we can better, and more quickly, adapt/enhance our control practices and further reduce the potential for people acquiring mosquito transmitted diseases.

As of today, all mosquitoes have tested NEGATIVE!


West Umatilla Mosquito Control District

Dedicated to the Protection of Public Health Through the Reduction of Public Health Vectors