The Maryland Department of Agriculture (MDA) announces the first state detection of a West Nile virus (WNV) mosquito pool in Maryland in 2009. State Department of Health and Mental Hygiene (DHMH) laboratory results confirmed the presence of WNV in mosquitoes (Culex pipiens) collected on July 21 in the Pocomoke City, Worcester County. MDA mosquito control personnel are continuiong to work aggressively to reduce mosquito populations across the state, including aerial spray operations on the Eastern Shore.

"Because of spring rains in much of the state, mosquito populations are high and we know that West Nile virus may be present throughout Maryland. It typically appears at this time in the summer, so we are not surprised with this positive finding," says Secretary of Agriculture Buddy Hance. "The confirmation of virus-positive mosquitoes serves as a reminder to all residents to continue protecting themselves against mosquito bites and to conduct backyard mosquito control activities in addition to MDA's routine surveillance and spray activities."

The MDA mosquito control office, in cooperation with DHMH, is conducting state-wide surveillance activities to monitor mosquito populations and detect mosquito-borne viruses of public health concern. Surveillance activities for adult mosquitoes use traps and landing rate counts. Mosquito control activities conducted by MDA include larviciding and spray programs for adult mosquitoes in communities that voluntarily participate in the agency's program. Additional mosquito-borne disease surveillance is conducted by the U.S. Department of Defense on military installations in Maryland.

"Mosquito control remains especially important to decreasing the risk of infection with all mosquito borne diseases," said Michael Cantwell, MDA chief of mosquito control. "MDA is taking appropriate steps for mosquito surveillance and mosquito control activities in participating Maryland jurisdictions through the end of September