Encephalitis
Encephalitis is an inflammation (swelling) of the brain. Encephalitis is usually caused by a virus, but other things, including bacteria, may cause it as well. Although encephalitis sounds scary, it's rarely serious.
The illness occurs in two forms — a primary form and a secondary form. The primary form of the disease is more serious, while the secondary form is more common. But because of the milder nature of secondary encephalitis, doctors actually see more cases of primary encephalitis. Seeing your doctor and receiving timely treatment is important because the course of the disease is unpredictable.
Causes
Encephalitis (pronounced: in-seh-fuh-lye-tus) is typically caused by three different groups of viruses. The herpes viruses fall into one group. They include chickenpox, EBV (Epstein-Barr virus - the virus that causes mono), and herpes simplex (the virus that causes cold sores). The second group is viruses that are transmitted by insects. Viruses like West Nile virus, which is transmitted through a mosquito bite, and Lyme disease and Rocky Mountain spotted fever, which are transmitted thorough tick bites, can also cause encephalitis. The third group of viruses is made up of common childhood viral infections. These include measles, mumps, and German measles. Because lots of countries immunize against these diseases, it's rarer today that a person will develop encephalitis as a result of an illness like measles or mumps.
Some cases of encephalitis are mild and symptoms only last for a short time. However, it is possible to develop a severe case of encephalitis that can be serious and possibly even life threatening. When a person has encephalitis, his or her brain becomes inflamed - inflammation means swelling and redness.
Signs and Symptoms
Encephalitis may cause fever, headache, poor appetite, loss of energy, or just a general sick feeling. In more severe cases, other symptoms may occur, including:
- high fever
- severe headache
- sensitivity to light (called photophobia, which means light hurts your eyes)
- nausea and vomiting
- stiff neck
- confusion
- sleepiness, difficulty waking, or unconsciousness
- convulsions (seizures).
Treatment
Treatment for encephalitis depends on the virus that caused it. People with mild cases of encephalitis can recover at home as long as they're watched carefully by a parent or other adult in the household. Most cases of encephalitis just run their course and the person gets better on his or her own.
Some viruses that cause encephalitis can be treated with medication. For example, acyclovir, an antiviral drug, can help treat encephalitis caused by the herpes simplex virus. In addition, steroid medications may be used to reduce swelling in the brain (these aren't the same as the dangerous performance-enhancing steroids that some athletes use). Because antibiotics are not effective against viruses, they're not used to treat viral encephalitis.
Severe cases of encephalitis require a hospital stay so the patient can be carefully monitored and medical treatment is close at hand if it's needed. For people who have had severe encephalitis that has affected some of the brain's functions, doctors may recommend physical therapy or speech therapy to help with recovery.
Prevention
The best way to prevent encephalitis is to avoid getting the viruses that can cause it. Regular hand washing will help limit the spread of some of these germs. Staying as healthy as possible by eating a balanced diet and getting plenty of rest can help keep your immune system in shape. Immunizations are also an important way to protect people from diseases like chickenpox and measles.
In areas where viruses are transmitted by insect bites, protect yourself by wearing long sleeves and pants and applying an insect repellent. Also, try to avoid unnecessary outdoor activities at dawn and dusk when mosquitoes are most likely to bite.
To protect yourself and your family against mosquito-borne encephalitis during an outbreak of the disease:
- Dress to protect yourself. Wear long-sleeved shirts and long pants if you're outside between dusk and dawn.
- Apply mosquito repellent. Use repellent with a 10 percent to 30 percent concentration of DEET to your skin and clothing. Choose the concentration based on the hours of protection you need — a 10 percent concentration is effective for about two hours, while higher concentrations last longer. Don't use DEET on the hands of young children or on infants under 2 months of age. Instead, cover your infant's stroller or playpen with mosquito netting when outside.
- Avoid mosquitoes. Refrain from unnecessary activity in places where mosquitoes are most prevalent.
- Keep mosquitoes out of your home. Repair holes in screens on doors and windows.
- Get rid of water sources outside your home. Eliminate standing water in your yard, where mosquitoes can lay their eggs. Empty birdbaths, drains, wheelbarrows and flowerpots, and remove old tires and unused containers that might hold water. Drain puddles when possible. Clean your gutters and drain flat roofs regularly.
- Take advantage of nature's mosquito-controlling creatures. Fill ornamental pools with mosquito-eating fish. Consider placing houses for other mosquito eaters, such as purple martins and bats, in your yard.
- Look for outdoor signs of viral disease. Keep an eye out for sick or dying birds and report them to your local health department.
Informations obtained from National Institute of Health.