West Nile virus has its name from an East African River, or the world’s longest river that stretches through the Mediterranean. First identified in 1937 from an infected person in the West Nile District of Uganda, this virus only made its way into the United States by 1999, possibly through the Middle East. As of September 23, 2002, 1,963 laboratory-tested positive human cases have been identified in 32 states and the District of Columbia, and caused 93 deaths, as reported by the US Centers for Disease Control (CDC).

How is the West Nile Virus spread? It is spread when infected mosquitoes bite and infect birds, horses, other animals and humans. Most people who become infected with West Nile virus do not show symptoms or only show mild symptoms. On rare occasions, infection can be severe and cause death. The virus is not transmitted directly from person to person, hence a disease-carrying insect or vector must be present for human-human transmission to take place. There has not been any reported fatality of West Nile virus in the state of Oklahoma; however as of September 23, 2002, four laboratory-tested positive human positive cases have been reported in the state, according to the Oklahoma State Department of Health.
Who is at Risk for getting the west Nile Virus? Everyone who lives in an area, state or country where the virus has been identified, can get the virus. However person over 50 years of age have the higher risk, and those over 70 years of age who are hospitalized with the disease have a highest risk for fatality. Individuals with weakened immune systems are also at a higher risk of getting the virus.

What is the relationship between the West Nile Virus and birds or animals? Infected mosquitoes transmit the virus to birds and other animals by feeding on them, making them sick and causing deaths. Dead birds and other animals that are laboratory-tested positive in a community are good indicators for the presence of the virus in that community. Humans become infected when infected mosquitoes feed on humans, just as they feed on birds and animals.

What are the signs and symptoms of the disease and what is the incubation period? The incubation period is 3-14 days. The incubation period of a disease is the time that elapses from when an individual is exposed to a disease, to when signs and symptoms first appear. Signs and symptoms of West Nile virus include: sudden fever with rash, headache, muscle aches, vomiting, loss of appetite and swollen lymph nodes. The most conclusive test of the virus is the presence of positive test for the virus from a blood or spinal fluid sample. Complication from West Nile virus include: meningitis or inflammation of the meninges or covering of the brain and encephalitis or inflammation of the brain itself.

How can the West Nile Virus be prevented? There is no vaccine as yet for West Nile virus, hence prevention should involve: 1) reducing the number of vector mosquitoes through actions taken by individuals and municipal authorities, and 2) preventing vector mosquitoes from biting humans by using mosquito repellents; avoiding locations where vector mosquitoes are biting; and using barrier methods, such as window screens or long-sleeved clothing.

Is the use of mosquito repellent beneficial? Yes! Repellents should contain the active ingredient called DEET (N, N-diethyl-3-methylbenzamide) in concentration between 10-50 %. Repellents used on children should contain less than 10% of DEET. Carefully read manufacturer’s instruction before using mosquito repellents.

What are other mosquito control methods? wear long-sleeved shirts and long pants whenever outdoors; place mosquito netting over infant carriers when outdoors with infants; stay indoors at dawn, dusk, and early evening, which are peak mosquito biting times; install or repair window and door screens so mosquitoes cannot get indoors. Reduce the number of mosquitoes by doing the following: draining sources of standing water; empty water from flower pots, birdbaths, swimming pool covers, buckets, barrels, and cans; drain clogged rain gutters and clean them out.; remove discarded tires, and other items that collect water; Be sure to check for containers or trash in places that may be hard to see, such as under bushes or under your home. Environmental cleanliness and protecting your body from mosquito bites are the best protection form the West Nile Virus.