West Nile Virus

Basic Facts
  • Most people who are bitten by mosquitoes are not bitten by an infected mosquito
  • Most people who are bitten by an infected mosquito do not get sick
  • West Nile is a virus that mainly infects birds
    • Mosquitoes that feed on infected birds take in the virus
    • They can transmit it to other animals and humans they bite later
    • The virus is not passed on person to person
  • Most people who do get sick get a mild disease
  • A very few people can develop severe disease
Virus Spread
As of August 2012, West Nile Virus has not been identified in humans in Santa Cruz County. West Nile is again expected to spread to Arizona sometime in the next few months, or next year. It is spread over large distances via migratory birds.
Logo for the Fight the Bite campaign.
The virus can be transmitted to a person only by a mosquito that was previously infected by an infected bird. The risk of individuals becoming infected is very low, and can be further reduced by following the guidelines below.

Infection Reduction Guidelines
Breeding Sites
Help reduce the number of mosquitoes by taking these simple steps to eliminate breeding sites for mosquitoes:
  • Change water in flower vases, planters, and animal water bowls 2 or 3 times week.
  • Get rid of all standing water in your yard. Check your yard 2 or 3 times per week, especially after rains, and remove water from cans, bottles, buckets, old tires, or anything that will hold water. Even ¼ inch of water on top of a can lid can allow mosquitoes to breed.
  • Keep grass and weeds cut short.
  • Repair leaky faucets that can cause puddles, and make sure rain gutters are not clogged.
Bite Precautions
Avoid being bitten by mosquitoes by taking these precautions:
  • Avoid being outdoors in the late afternoon and evening hours when mosquitoes are most active.
  • Use insect repellants. Repellants containing D.E.E.T. are considered most effective. Always follow label instructions, especially when treating children.
  • Wear lightweight clothing that covers arms and legs (long-sleeves and long pants).
Fight the Bite campaign poster featuring a crossed out mosquito.