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posted on July 29, 2013 15:16

People need to take precautions with mosquitoes as evidence of increasing West Nile virus activity grows in Idaho.

Routine testing of Idaho mosquitoes verified the presence of West Nile infected mosquitoes in mid-June. On Friday, July 26th,  Idaho announced the first cases of human and equine infections in the state. A second human infection was reported the following Monday. Both of the human infections are men in their 40s from Payette County. One of the two infected people required hospitalization.

Nine other counties in southwest and southern Idaho are also reporting WNV-positive mosquitoes -- Ada, Adams, Canyon, Gem, Gooding, Owyhee, Twin Falls, Valley and Washington counties. Infections have been reported in two unvaccinated horses in Ada and Canyon counties.

West Nile virus is usually contracted from the bite of an infected mosquito; it is not spread from person-to-person through casual contact. Symptoms of infection often include fever, headache, body aches, nausea, and sometimes swollen lymph glands or a skin rash. In some cases the virus can cause severe illness, especially in people older than 50. To reduce the likelihood of infection, people are advised to avoid mosquitoes, particularly between dusk and dawn when mosquitoes are most active. In addition, you should:

  • Apply DEET or other EPA-approved insect repellent to exposed skin and clothing. Carefully follow instructions on the product label, especially for children.
  • Cover up exposed skin when outdoors.
  • Insect-proof your home by repairing or replacing screens.
  • Reduce standing water on your property. Check and drain toys, trays or pots which may hold water. Change the water in bird baths and static decorative ponds weekly as they may provide a suitable mosquito breeding habitat.

West Nile virus does not usually affect domestic animals, but it can cause severe illness in horses and certain species of birds. Although there is no vaccine available for people, there are several vaccines available for horses. People are advised to vaccinate their horses annually.

Last year, 17 people in Idaho reported West Nile virus infections, with West Nile activity reported in 11 Idaho counties. In 2006, Idaho led the nation in West Nile illnesses with almost 1,000 infections, which contributed to 23 deaths.

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