West Nile Virus
To report a dead crow, hawk or falcon, call the Camden County West Nile Virus Hotline: 1-800-99-9045 Monday-Friday (8:30 a.m. to 4:30 p.m.) (856) 783-1333 after hours and on weekends.
WHAT IS WEST NILE VIRUS?
West Nile virus (WNV) is a mosquito-borne virus and is closely related to St. Louis encephalitis (SLE) virus. SLE has occurred in humans in Camden County but not recently. SLE virus is most prevalent in the southeastern and mid-western United States. However, WNV is typically found in Africa, Europe, and West Asia (primarily in countries bordering the Mediterranean Basin). It is not known how the WNV got to the United States. Scientists believe the virus was probably in the Eastern U.S. for several months before the outbreak in humans.
VECTORS OF WNV
WNV is transmitted through the bite of an infected mosquito. It has been isolated from at least 43 species of mosquitoes throughout the world. In most countries, mosquitoes belonging to the genus Culex are the primary vectors. In the United States, the common house mosquito (Culex pipiens) is considered to be the principal vector species. Culex pipiens is the principal mosquito species found in urban and suburban environments. The larvae are commonly found in polluted water collecting in roadside ditches, catch basins, artificial containers such as old tires, and in swimming pools that are not in use. Although Culex pipiens prefer avian hosts for its blood meal, some of these mosquitoes will readily bite humans and other mammals.
WNV TRANSMISSION CYCLE
WNV infections are characterized by a bird-mosquito cycle. The European transmission cycle is similar to that of St. Louis encephalitis virus in the United States. Therefore, WNV in the United States is thought to have a similar mode of transmission.
ANSWERS TO COMMON QUESTIONS
Q. How do people get the West Nile virus?
A. After being bitten by a mosquito that is infected with West Nile virus.
Q. Can you get the West Nile virus from a person?
A. No. West Nile virus can only be contracted through the bite of an infected mosquito.
Q. Can you get the West Nile virus from birds?
A. There is no evidence that a person can get the virus from handling live or dead infected birds. West Nile virus can only be contracted through the bite of an infected mosquito.
Q. What happens if you're infected with the West Nile virus?
A. Most infected people show no symptoms of disease. Mild symptoms include fever, headache, and body aches, often with skin rash and swollen lymph glands. More severe cases can be marked by headache, high fever, stiff neck, disorientation, coma, tremors, paralysis and rarely, death.
Q. How fatal is this disease?
A. Approximately 3% - 15% of the symptomatic cases result in death. Fatalities are more likely in people over the age of 50.
Q. What is the treatment?
A. Treatment is supportive only as there is no known cure for West Nile fever.
Q. How common is West Nile virus in the U.S.?
A. In 1999, there were 63 confirmed Cases of West Nile fever in the US (all in the New York City area), representing the first recorded cases of this infection in North America. It is not known how common West Nile virus is or will become in the U.S., however, in Europe West Nile Virus has caused sporadic human cases or outbreaks, occurring at irregular intervals.
To reduce the annoyance of mosquito bites and prevent transmission of mosquito-borne infections, a few common sense measures should be followed. These include:
ò Avoid very shaded areas where mosquitoes may be resting during daylight.
ò Limit outdoor activity in the evening when mosquitoes are most active.
ò Wear clothing that protects your skin such as long-sleeved shirts and pants.
ò Use insect repellents. Repellents that contain 20-30% DEET can be very effective in preventing insect bites: Use repellents only as directed; using more DEET than necessary will not improve protection. Do not apply repellent to children's hands or let them apply it themselves to avoid getting repellent in their eyes. Do not use repellents on infants. As with all products, the user should follow the manufacturer's usage recommendations.
Finally mosquito populations can be reduced on your property and in your neighborhood by eliminating standing water that collects in unused birdbaths, boats, buckets, tires, unused pools, leaf filled roof gutters, plates under flowerpots and many other containers.
For additional information regarding the health aspects of WNV, please contact your personal physician or county health department.
For more information regarding mosquitoes, their biology or their control contact:
Camden County Mosquito Commission
DePalma Complex, Egg Harbor Road
Lindenwold, NJ 08021
Wild birds are the principal hosts of WNV. WNV has been isolated from a variety of avian species, including crows, ducks and pigeons. Birds are able to maintain a long-term infection. Consequently, migratory birds are considered to be instrumental in transporting the virus to new areas. Mammals are much less important in maintaining WNV infections, however, WNV has been isolated from several mammalian species as well as frogs. Therefore, the bird is the most common carrier of the virus and the mosquito is the vector that transmits the virus.
WNV IN HUMANS
When people become infected with WNV an influenza-like illness often follows. In humans, the virus has an incubation period of 3 to 10 days. Therefore, symptoms may appear suddenly and are often characterized by high fever, headache, backache, fatigue, and nausea. There is no specific treatment for persons infected with WNV nor is there a vaccine. Most people recover from infection completely within two weeks. However, 3% - 15% of cases result in fatalities. Most fatal cases occur in people greater than 50 years of age. Infected humans are not able to pass the infection to new mosquitoes or directly to other humans.
WNV IN BIRDS
Most birds do not normally show any symptoms of WNV infection. Rather they serve as natural reservoirs of the virus and are able to pass the virus to feeding mosquitoes. However, some avian species appear to be susceptible to the virus, displaying varying degrees of illness. Crows, chickens, ducks, gulls, and pigeons have been reported to show signs of illness ranging from encephalitis (inflammation of the brain), erratic walk and death.
WNV IN HORSES
Horses infected with WNV have been reported as having encephalitis with a moderate to high fatality rate in Europe and North Africa and in New York. Symptoms may include fever, staggering gait, weakness and paralysis.
Since many species of mosquito are common in New Jersey they and the problems they cause have been kept under control by governmental agencies for many years. Mosquitoes and birds have been monitored every year and this will continue.