We're unable to sign you in at this time. Please try again in a few minutes.
We were able to sign you in, but your subscription(s) could not be found. Please try again in a few minutes.
There may be a problem with your account. Please contact the AMA Service Center to resolve this issue.
Contact the AMA Service Center:
Telephone: 1 (800) 262-2350 or 1 (312) 670-7827  *   Email: subscriptions@jamanetwork.com
Error Message ......
JAMA Patient Page |

West Nile Virus FREE

Denise M. Goodman, MD, MS; Edward H. Livingston, MD
JAMA. 2012;308(10):1052. doi:10.1001/2012.jama.11678.
Text Size: A A A
Published online

West Nile virus is widely distributed throughout the world and first appeared in the United States in 1999. The virus is typically carried from infected birds (the host animal) to humans and other mammals through mosquito bites.


About 80% of people infected with the virus have no symptoms. Those who do usually start to feel sick 3 to 14 days after being bitten by an infected mosquito. Most people who get sick develop West Nile fever. Symptoms include fever, headache, fatigue, body aches, muscle pain, joint pain, and chills. More than half of sick people report a rash. Symptoms usually last for 3 to 6 days but some people have been sick for weeks. A few people (approximately 1 in 150 infected persons) develop severe disease with serious symptoms. The virus invades the nervous system, causing encephalitis (inflammation of the brain) or meningitis (inflammation of the tissues surrounding the brain and spinal cord). Symptoms of severe disease include headache, fever, stiff neck, disorientation, coma, tremors, convulsions, muscle weakness, and paralysis. Severe disease may last for weeks and cause permanent injury or, in some cases, death.


Tests for West Nile virus may include blood work, computed tomography (CT) or magnetic resonance imaging (MRI) scans of the head, and lumbar puncture (spinal tap) for cerebrospinal fluid (the natural fluid that bathes the brain and spinal cord).


Spread of the disease is effectively managed by mosquito control. Very small amounts of pesticides are applied via ground and aerial spraying. These applications have been shown to result in negligible pesticide exposure and no adverse health effects to the public.


  • Use insect repellent.

  • Many mosquitoes are active between dusk and dawn. Use insect repellent and wear long sleeves and pants at these times or consider staying indoors during these hours.

  • Eliminate mosquito breeding areas—anywhere with standing water, such as flowerpots or buckets.

  • Make sure your windows have screens that are in good condition.

  • You cannot get West Nile virus by casual contact such as touching an infected person.


There is currently no specific treatment for West Nile virus infection. Since it is caused by a virus, not bacterium, antibiotics do not help. Most treatment is aimed at supporting the body's functions until the infection is cleared. You should see your doctor if you have symptoms. If your symptoms are severe, seek care in an emergency department.



To find this and previous JAMA Patient Pages, go to the Patient Page link on JAMA 's website at www.jama.com. Many are available in English and Spanish.

Sources: National Institutes of Health, Centers for Disease Control and Prevention, Cornell University Department of Entomology

The JAMA Patient Page is a public service of JAMA. The information and recommendations appearing on this page are appropriate in most instances, but they are not a substitute for medical diagnosis. For specific information concerning your personal medical condition, JAMA suggests that you consult your physician. This page may be photocopied noncommercially by physicians and other health care professionals to share with patients. To purchase bulk reprints, call 312/464-0776.





Also Meets CME requirements for:
Browse CME for all U.S. States
Accreditation Information
The American Medical Association is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The AMA designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 CreditTM per course. Physicians should claim only the credit commensurate with the extent of their participation in the activity. Physicians who complete the CME course and score at least 80% correct on the quiz are eligible for AMA PRA Category 1 CreditTM.
Note: You must get at least of the answers correct to pass this quiz.
Please click the checkbox indicating that you have read the full article in order to submit your answers.
Your answers have been saved for later.
You have not filled in all the answers to complete this quiz
The following questions were not answered:
Sorry, you have unsuccessfully completed this CME quiz with a score of
The following questions were not answered correctly:
Commitment to Change (optional):
Indicate what change(s) you will implement in your practice, if any, based on this CME course.
Your quiz results:
The filled radio buttons indicate your responses. The preferred responses are highlighted
For CME Course: A Proposed Model for Initial Assessment and Management of Acute Heart Failure Syndromes
Indicate what changes(s) you will implement in your practice, if any, based on this CME course.


Spanish Patient Page: Virus del Nilo Occidental

Supplemental Content

Some tools below are only available to our subscribers or users with an online account.

0 Citations

Related Content

Customize your page view by dragging & repositioning the boxes below.

Articles Related By Topic
Related Collections
PubMed Articles