The announced Tuesday that mosquitoes caught last week as part of the Connecticut Mosquito Management Program in Old Greenwich have tested positive for the West Nile virus.
It is the first confirmation this summer that mosquitoes in town are carrying the virus which can cause symptoms ranging from slight fever, headache, rash, swollen lymph nodes, nausea, malaise and eye pain, to the rapid onset of severe headache, high fever, stiff neck, disorientation, severe muscle weakness, gastrointestinal symptoms, coma or even death, according to health officials.
The mosquitoes trapped (Culex pipiens) are generally bird and mammal biting which breed in standing water often found in artificial containers like discarded tires, birdbaths and catch basins. There haven't been any WNV related illnesses reported by Connecticut residents, according to the statement released by Greenwich health officials. There were 9 cases of West Nile virus reported in Connecticut last year, including one in Greenwich.
The Old Greenwich batch of mosquitoes trapped July 9, has put Greenwich on the virus map along with two other Connecticut cities—Stamford and Stratford, according to the statement.
Greenwich Director of Environmental Health Services Michael Long said the mosquitoes were trapped by the state in the stream that runs along the property on Harding Road, by the Metro-North Railroad tracks. He said it was not immediately known how many mosquitoes were caught.
"We want to use this as a tool to remind residents to protect themselves, use mosquito and bug repellent according to the directions on the packaging," Long said. He also said residents should remove any standing water or containers filled with water — including gutters — which will attract mosquitoes.
According to Long, the town's larvicide contractor began applying a second round of larvicide to the more than 6,000 catch basins in town. The applications are done every four to six weeks and probably will continue through October.
Long said that heavy rainstorms such as those which passed through Greenwich Sunday evening potentially can wash away the larvicide. "If residents are applying larvicide to their properties, they should readminister it," Long said.
Here is the statement issued by the Greenwich Health Department, complete with suggestions on how to combat the breeding of mosquitoes, and symptoms of the illness:
"The virus (WNV) is spread to humans by the bite of an infected mosquito, which becomes infected when it bites a bird carrying the virus. WNV is not spread by person-to-person contact or directly from birds to people. General symptoms occur suddenly between 5 – 15 days following the bite of an infected mosquito and range from slight fever, headache, rash, swollen lymph nodes, nausea, malaise and eye pain, to the rapid onset of severe headache, high fever, stiff neck, disorientation, severe muscle weakness, gastrointestinal symptoms, coma or death.
Most people who are bitten by an infected mosquito are able to fight off infection and experience mild or no symptoms at all. Some individuals, including the elderly and persons with compromised immune systems, WNV can cause serious illness that affects the central nervous system. In a minority of infected persons, especially those over 50 years old, WNV can cause serious illness, including encephalitis and meningitis. Infection can lead to death in 3 - 15% of persons with severe forms of the illness.
“The finding of WNV positive mosquitoes in Greenwich marks the time to emphasize that personal protection measures are extremely important against biting mosquitoes during the day and at night,” says Caroline Calderone Baisley, Director of Health. The following precautions should be taken when outdoors:
- Avoid outdoor activities at dawn and dusk when mosquitoes are most active.
- Wear long sleeved shirts and long pants.
- Use mosquito repellent according to the manufacturer’s directions on the label (10% or less DEET for children and no more than 30% DEET for adults). Always wash treated skin when returning indoors.
- Avoid application of repellents with DEET on infants and small children.
- Cover arms and legs of children playing outdoors.
- Cover playpens or carriages with mosquito netting.
- Don’t camp overnight near stagnant or standing water.
Eliminate standing water by:
- Getting rid of any water holding containers (old tires, etc.).
- Rake out puddles and drain ditches, culverts, gutters, pool and boat covers.
- Cover trash containers.
- Chlorinate your backyard pool and empty wading pools when not in use.
- Change the water in birdbaths daily.
- Keep grass cut short and shrubbery well trimmed around the house so adult mosquitoes cannot hide there.
- Ponds and stagnant water bodies that do not support fish, frogs or other amphibians that eat mosquito larvae may be treated with a biological control agent such as Bacillus thuringiensis israelensis (BTI). It is suggested that the Department of Health or Conservation be contacted when treatment is considered.