|
|
|
|---|---|
|
|
|
|
The Horse |
Health Features - West Nile Virus |
            
|
What is West Nile Virus? |
|
It is a form of encephalitis causing inflammation of the central nervous system (the brain and spinal cord). The virus was identified around 1935 and was known to be distributed in Africa, the Middle East and Southwest Asia. Occasional and sporadic outbreaks have been known to occur in some southern European countries. It was not known in the Americas prior to the outbreaks in 1999 that caused the deaths of humans and horses in New York state and the cancellation of the World Singles Driving Championships.The disease affects some species of birds, horses, cats, bats, humans and a number of other animals. Most horses (and humans) that contract the disease will have few if any symptoms , however in a small percentage of cases there will be a variety of symptoms which indicate that the central nervous system has been overwhelmed by the disease and in a few cases it will result in the deaths of the victim.These may include fever, headache (humans), and body aches, occasionally with skin rash and swollen lymph glands. More severe infection may be marked by headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, paralysis, and, rarely, death.
|
|
TransmissionWest Nile virus is spread by mosquitos, usually
Culex pipiens to be precise, and while the disease does not currently exist in the country, the influx of new mosquito and other foreign insects in the last few years should not make us feel secure against the possibility of future outbreaks of this disease. It should also be remembered that the source of the disease is usually infected birds so any species of mosquito would be capable of transmitting the virus.
Transmission directly from horse, human or bird to another of its species or any other species does not appear to be possible without the mosquito's bite providing blood to blood transmission. The likely suspect for the US outbreak is thought to be illiegally smuggled birds.
|
|
TreatmentThere is no specific treatment for this virus, but animals which show symptoms may be treated for the generic symptoms of encephalitis and provided with medications aimed at lessenning the severity of signs of central nervous system disturbance.
There is no reason to destroy a horse just because it has been infected with West Nile virus. Data suggest that most horses recover from the infection. There is no evidence that West Nile virus is transmitted between horses, furthermore the virus is detectable in the blood for only a few days. At this time there are not any vaccines available for the virus, but a measure of prevention for animals in infected areas, may be gained by taking precautions against mosquito bites through the use of insect repellants, rugs and mosquito eradication programmes on the farm.
|
|
Centre for Disease Control and Prevention(US) - West Nile Q & A
|
|
|
|
|
|
|
|
