No, mosquitoes are generally considered a nuisance pest, but they occasionally can transmit disease. Sixty-four different species of mosquitoes are known to occur in Ohio. While most cannot transmit West Nile virus, several mosquito species common to Ohio are known to be carriers of West Nile virus. Only female mosquitoes bite. They do this to get a blood meal for developing their eggs.
Many mosquitoes are most active two to three hours before and after dusk and again at dawn when the air is calm. This is the time when the females are most likely to bite. However, some species will feed at any time of the day.
Most people have become infected in summer or early fall when mosquitoes are most numerous.
Yes. During the winter months of 2000, health workers in New York City found over-wintering mosquitoes that contained evidence of West Nile virus.
No. During the last 3 years, the states reporting West Nile virus activity found many different bird species infected with West Nile virus. However crows and blue jays appear to be the most susceptible. This observation is not completely understood.
Yes. Other animals have also been found to be infected and have died from West Nile virus. During the year 2000, reports from the Eastern states found West Nile virus infecting 58 horses, two bats, a domestic rabbit, a cat, gray squirrel, and a chipmunk.
No. The virus is not spread by person to person contact, and there is no evidence that people can get the disease by handling infected animals.
Most people who are bitten by an infected mosquito will demonstrate no signs or symptoms. However, some will experience a mild infection with a slight fever, headache, body aches, and sometimes a skin rash or swollen lymph glands. Symptoms generally occur five to 15 days after being bitten by an infected mosquito. A very small number of people will suffer from a severe infection that is marked by a rapid onset of a high fever, a severe headache, neck stiffness, nausea or vomiting, confusion, muscle weakness or paralysis, seizures, coma, and rarely, death.
While everyone exposed to a mosquito that carries the West Nile virus is susceptible, people at greatest risk are those older than 50. Those who are immuno-compromised may also be at greater risk. During the outbreak in New York City in 1999, everyone who died from West Nile virus infection was 75 years of age or older. However, in 2001, 2 people in their 40s died from West Nile virus infection.
Check out the symptoms page. To diagnose a West Nile virus infection, a doctor will need to test either blood or cerebrospinal fluid from a spinal tap for antibodies to the virus. A second blood test is required two to three weeks later to confirm the diagnosis.
Check out the treatment page. No, there is no specific treatment for West Nile virus infection. While many people will not know that they have been exposed, nearly all of those with symptoms will fully recover. However, in some severe cases, hospitalization may be needed. There is no vaccine for West Nile virus. There are no antibiotics or antiviral medications that can be used in the treatment of West Nile virus. All care is supportive.
Yes. There are several other viruses circulating among mosquitoes in Ohio that can cause encephalitis. Although each of these viruses is somewhat different, prevention is basically the same--reduce the mosquito population and protect yourself from mosquito bites, especially during the summer and early fall.
Check out the prevention page. You can reduce the number of mosquitoes around your home and neighborhood by eliminating places where they lay their eggs. Young mosquitoes are aquatic, and they must have standing water to develop from egg to adult.
Check out the prevention page. The best way is to avoid being bitten by mosquitoes. Use personal protection while outdoors when mosquitoes are present.
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