2017-08-30 / Front Page

West Nile virus found during area mosquito sampling

by Kate Evans

The Berkeley County Health Department issued a public health alert last Thursday, August 24 that West Nile virus was detected by the West Virginia Office of Laboratory Services in a mosquito sampling collected in Berkeley County. West Nile virus is a mosquitoborne illness that affects the nervous system.

Area residents are reminded to protect themselves from mosquito bites to avoid contracting the virus. Health officials urge residents to wear longsleeves and long pants and use DEET-containing or other EPA-recommended insect repellents when outdoors.

West Nile virus (WNV) is an arbovirus (arthropodborne virus) transmitted by mosquitoes and was first identified in the 1930s in Uganda. West Nile virus infections were first observed in humans and birds in New York City in 1999. Since then, the virus has spread to all states in the continental United States.

Mosquito populations can be reduced by removing standing water and trash on properties to eliminate potential breeding sites, say health officials.

Standing water can collect in flowerpots, bird baths, buckets, swimming pool covers, tarps, clogged rain gutters and tires.

Mosquito surveillance is conducted annually through a grant from the West Virginia Bureau of Public Health Division of Infectious Disease Epidemiology to monitor mosquito activity and diseases spread through mosquito bites and determine if disease-carrying adult mosquitoes are present. Maryland and Pennsylvania also monitor and test for the disease.

Other arboviruses that can be carried by infected mosquitoes include La Crosse encephalitis virus, St. Louis encephalitis virus and Eastern equine encephalitis. Travel-related mosquitoborne illnesses include dengue fever, chikungunya, malaria and Zika virus.

Local, regional cases

Berkeley County had one suspected case of West Nile virus last year. West Virginia had nine confirmed or probable cases of West Nile virus in 2012, one of which was in Morgan County.

As of August 22, 2017, a total of 45 states and the District of Columbia have reported West Nile virus infections in people, birds, or mosquitoes this year. There have been no human cases of the disease reported in West Virginia or Maryland this year.

Human West Nile virus infections have been reported in Pennsylvania and Virginia. Both states have reported West Nile virus infections in mosquitoes, birds, sentinel animals or veterinary animals to the CDC.


Milder symptoms of the disease include fever, headache, body aches, nausea, vomiting, swollen lymph glands or a skin rash on the chest, stomach or back. These symptoms occur in 20% of those who become infected with the virus and may last several days to several weeks.

Symptoms generally develop three to 14 days after being bitten by the infected mosquito. About 80% of those infected with West Nile virus will have no symptoms at all. Most people with this type of West Nile virus disease recover completely, but fatigue and weakness can last for weeks or months.

Less than one percent of people who are infected with West Nile virus will develop a serious neurologic illness such as encephalitis or meningitis (inflammation of the brain or surrounding tissues).

The symptoms of neurologic illness can include headache, high fever, neck stiffness, disorientation, coma, tremors, vision loss, numbness, convulsions, muscle weakness and paralysis. People may need to be hospitalized in severe cases of West Nile virus, which can sometimes be fatal.

People over age 50 and those with compromised immune systems or that have conditions like cancer, diabetes, hypertension or kidney disease or who have had organ transplants are at higher risk of getting very ill from the disease if they get infected through a bite.

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