West Nile virus is a virus of the family Flaviviridae that mainly affects birds, and typically found in tropical and temperate regions. However, this virus is also known to affect humans, horses, cats, dogs, skunks, squirrels, crocodiles, alligators and bats. When it affects humans it is commonly spread through the bite of an infected mosquito. West Nile virus can cause potentially serious diseases in humans even though in most of the cases people have no obvious symptoms of the infection. However, one in every 150 infected individuals will develop serious illness that may last for a couple of weeks and leave permanent neurological damage to the patient.
Symptoms of West Nile virus infection
West Nile virus infection can manifest in many different ways. In most of the cases, the infection is asymptomatic. However, some patients may have a mild febrile syndrome known as the West Nile Fever, characterized by an elevation of temperature above the normal range. In these patients, the incubation stage lasts from 2 to 8 days and when the symptoms occur, they include headache, chills, excessive sweating, weakness, swelling of the lymph nodes. It usually lasts up to 10 days.
The most severe symptoms are observed in patients with a neuroinvasive disease known as the West Nile meningitis. Symptoms include decreased levels of consciousness, deep tendon reflexes, and movement disorders. Mortality rates are somewhere around 4.5%, but only of the severe infections.
Prevention of West Nile virus
The West Nile virus affects humans through mosquito vectors. The only way to prevent and control this disease is by mosquito control and elimination of mosquito breeding sites.
People should also make sure there are no suitable breeding sites for mosquitoes in their closer environment. The best way to do so is to empty standing water from flower pots, barrels and other containers, and to change the water in pet dishes on the regular basis. Wading pools should also be kept empty whenever they are not used.
People should also be encouraged to use insect repellent whenever they are outside. The best ones contain EPA-registered active ingredient, and they should be used according to directions on the package.
Mosquitoes are very active during the night. Therefore, it is strongly advised to wear long sleeves and pants in these times or stay indoors. Therefore, it is also important to keep the mosquitoes away from the house, by sealing the windows and doors with proper screens, to ensure that mosquitoes cannot enter the house.