Anyone can develop encephalitis. Factors that may increase the risk of the condition include:
May 15, 2014
- Age. Some types of encephalitis are more prevalent or more severe in certain age groups. In general, young children and older adults are at greater risk of most types of viral encephalitis. Encephalitis from the herpes simplex virus tends to be more common in people 20 to 40 years of age.
- Weakened immune system. People who have HIV/AIDS, take immune-suppressing drugs, or have another condition causing a compromised or weakened immune system are at increased risk of encephalitis.
- Geographic regions. Mosquito-borne or tick-borne viruses are common in particular geographic regions.
- Season of the year. Mosquito- and tick-borne diseases tend to be more prevalent in spring, summer and early fall in many areas of the United States. In warmer areas of the U.S., however, mosquitoes and ticks may be present year-round.
- Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed Feb. 15, 2014.
- Encephalitis and meningitis fact sheet. National Institute of Neurological Disorders and Stroke. http://www.ninds.nih.gov/disorders/encephalitis_meningitis/detail_encephalitis_meningitis.htm. Accessed Feb. 17, 2014.
- Encephalitis. The Merck Manuals: The Merck Manual for Health Care Professionals. http://www.merckmanuals.com/professional/neurologic_disorders/brain_infections/encephalitis.html. Accessed Feb. 17, 2014.
- Hardarson HS. Acute viral encephalitis in children and adolescents: Clinical manifestations and diagnosis. http://www.uptodate.com/home. Accessed Feb. 15. 2014.
- Johnson RP, et al. Viral encephalitis in adults. http://www.uptodate.com/home. Accessed Feb. 15, 2014.
- Hardarson HS. Acute viral encephalitis in children and adolescents: Pathogenesis and etiology. http://www.uptodate.com/home. Accessed Feb. 15, 2014.
- Hardarson HS. Acute viral encephalitis in children and adolescents: Treatment and prevention. http://www.uptodate.com/home. Accessed Feb. 15, 2014.
- FAQ: Insect repellant use and safety. Centers for Disease Control and Prevention. http://www.cdc.gov/westnile/faq/repellent.html. Accessed Feb. 17, 2014.
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