Encephalitis is an inflammation of the brain. When the brain becomes inflamed-swollen and irritated-normal blood flow to the brain is altered, leading to symptoms such as confusion, fever, and severe headache. Encephalitis is rare.

If you develop signs of encephalitis, with fever, muscle weakness, and confusion, you should seek medical care immediately.

There is no specific therapy. In more severe cases, intensive supportive therapy is indicated, i.e. hospitalization, intravenous (IV) fluids and nutrition, airway management, ventilator support if needed, prevention of secondary infections (pneumonia, urinary tract, etc.), and good nursing care.

Back to TopAn Arboviral Encephalitis is an infectious disease that affects the brain. The disease is caused by a virus which attacks the brain, destroys some nerve cells and causes brain inflammation and swelling. Encephalitis arboviruses belong to several families of viruses that usually infect birds and are transmitted from bird to bird by mosquitoes. The name "ar-bo-virus" comes from the fact that they are transmitted by arthopods (insects and other "bugs").

In horses that do become clinically ill, the virus infects the central nervous systems and causes symptoms of encephalitis. Clinical signs can include: loss of appetite, depression, fever, weakness of hind limbs, paralysis of hind limbs, impaired vision, ataxia, head pressing, aimless wandering, convulsions, inability to swallow, circling, hyperexcitability or coma.

There is no specific treatment for West Nile virus other than supportive veterinary care standard for animals infected with a viral agent. Data suggest that most horses do recover from the infection.

All residents of areas where virus activity has been identified are at risk of getting West Nile encephalitis; persons older than 50 years have the highest risk of severe disease. There have been numerous cases of humans being infected with the virus. Centers for Disease Control West Nile Virus Home Page

No symptoms in most people - Approximately 80% of people who are infected with WNV will not show any symptoms at all. Mild symptoms in some people - Up to 20% of the people who become infected will display mild symptoms, including fever, headache, body ache, nausea, vomiting and sometimes swollen lymph glands or a skin rash on the chest, stomach and back. Symptoms typically last a few days. Serious symptoms in a few people - About one in 150 people infected with WNV will develop severe illness.

West Nile virus is a flavivirus commonly found in Africa, West Asia, and the Middle East. It is closely related to St. Louis encephalitis virus found in the United States. The virus can infect humans, birds, mosquitoes, horses and some other mammals. West Nile fever is a case of mild disease in people, characterized by flu like symptoms. West Nile fever typically lasts only a few days and does not appear to cause any long-term health effects.

Eastern equine encephalitis (EEE) is a member of the family Togaviridae, genus Alphavirus, and is closely related to western and Venezuelan equine encephalitis viruses. It occurs primarily in the eastern half of the US. Because of the high case fatality rate, EEE is regarded as one of the more serious mosquito-borne diseases in the United States. The primary EEE transmission cycle is between birds and mosquitoes. Several species of mosquitoes can become infected with EEE virus.

iI is a good idea to check one's body at the end of the day to make sure none have latched on. In frequent trips there, we have never encountered the ticks or heard of anyone who has contracted the disease BUT there are reported cases in the Altai. See www.mdtravelhealth.com for more info.

By the bite of a mosquito (primarily one of the Culex species) that is infected with West Nile virus. The disease is an infection of the brain that can be transmitted to humans by mosquitoes that have bitten infected birds. Most people who become infected with West Nile virus will either never get sick or develop flu-like symptoms. But the disease can be deadly for those with weakened immune systems and the elderly.

Most infections are mild and symptoms include fever, headache, and body aches, often 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.