State Reports First Mosquitoes Positive for West Nile Virus in
Stonington

Hartford – The State Mosquito Management Program today announced that mosquitoes trapped in
Stonington on June 11, 2008 have tested positive for West Nile virus (WNV). These are the first
WNV-positive mosquitoes identified by the Connecticut Agricultural Experiment Station (CAES)
this year.
“The isolation of WNV this early in the season from Culex salinarius warrants continued
monitoring,” said Theodore G. Andreadis, Ph.D., Chief Medical Entomologist, CAES. “Based on
past experience, WNV activity in mosquitoes will continue to increase through the summer and
early fall. Fortunately, Connecticut has an extensive statewide mosquito monitoring program.”
Culex salinarius is a mosquito species abundant in coastal salt marshes that will feed on people
and is one of the species that has been identified with WNV in Connecticut in prior years. In 2007,
Culex pipiens mosquitoes trapped in Manchester on June 27 were the first in Connecticut to test
positive for WNV. Overall, WNV in mosquitoes was identified in 18 towns.
As of June 9, 2008, human cases were reported in five states this season: Arizona, Mississippi
Oklahoma, Tennessee, and Texas. In addition, WNV activity in birds, animals or mosquitoes was
identified in the following states: Alabama, California, Florida, Illinois, Indiana, Louisiana, South
Carolina, Texas, and Utah. The WNV-positive mosquitoes collected in Stonington, Connecticut are
the first findings in the northeastern United States this season.
“This is the tenth year that West Nile virus has been found in Connecticut. The recent
announcement of WNV-positive mosquitoes in Stonington should be taken seriously,” said J.
Robert Galvin, M.D., M.P.H., M.B.A., Department of Public Health (DPH) Commissioner.
“Residents, particularly the elderly, should take precautions to avoid mosquito bites during the
mosquito season, especially in areas where WNV is identified.”
In 2007, four people were confirmed with WNV infection in Connecticut and included residents of
Darien, Hartford, New Haven and Woodbridge. There were no fatalities. No human cases of
eastern equine encephalitis (EEE) were identified.

The CAES maintains a network of 91 mosquito-trapping stations in 72 municipalities throughout
the state. Mosquito traps are set Monday – Thursday nights with trapping conducted at each site
every ten days on a rotating basis. Mosquitoes are grouped (pooled) for testing according to
species, collection site, and date. Each pool is tested for the presence of viruses of public health
importance. Positive findings are reported to local health departments, in press releases and on the
CAES web site.
Since 2000 there have been significant decreases in the numbers of dead bird sightings reported and
those testing positive for WNV infection. Starting in 2006 and continuing during 2008, deaths of
wild birds are not used to evaluate the risk of WNV. Monitoring and risk assessment for WNV
emphasizes mosquito trapping and testing results. In addition, the DPH Laboratory provides testing
for hospitalized patients with suspected WNV related illnesses.
Precautions to avoid mosquito bites include:
• Minimize time outdoors at dusk and dawn
• Be sure door and window screens are tight fitting and in good repair
• Wear shoes, socks, long pants, and long-sleeved shirts. Clothing material should be tightly
woven
• Use mosquito netting when sleeping outdoors
• Consider using mosquito repellent when it is necessary to be outdoors and always use them
according to label instructions
• The most effective repellents contain DEET or Picaridin
• When using DEET use the lowest concentration effective for the time spent outdoors (for
example, 6% lasts approximately 2 hours and 20% for 4 hours) and wash treated skin when
returning indoors. Do not apply under clothing, to wounds or irritated skin, the hands of
children, or to infants less than 2 months.
Measures to reduce mosquitoes around the home include:
• Dispose of water-holding containers, such as ceramic pots, used tires, tire swings
• Drill holes in the bottom of containers such as those used for recycling
• Clean clogged roof gutters
• Turn over objects that may trap water when not in use such as wading pools and
wheelbarrows
• Change water in bird baths on a weekly basis
• Clean and chlorinate swimming pools, and when not in use, pool covers
• Use landscaping techniques to eliminate areas where water can collect on your property

Additional resources for information include:
• The Connecticut Mosquito Management Program Web site at www.ct.gov/mosquito
• The Centers for Disease Control and Prevention Web site at www.cdc.gov

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