GRAND RAPIDS, Mich. - Mosquito surveillance conducted by the Kent County Health Department (KCHD) revealed an unusually high number of mosquitoes with West Nile virus.

Officials say no human cases have been reported, but test results led health experts to believe a rise in human cases is possible this year.

"Ive been working with West Nile virus here in west Michigan for over fifteen years,"said Adam London, Administrative Health Officer at KCHD. "In that time, ever since its arrived, we were especially vulnerable back when it first arrive because everyone was susceptible to it. Since that time, I don't recall a year where we had surveillance data that was more concerning than what we have right now."

Since late May, the health department tested more than 16,000 Culex mosquitoes, which typically carry the virus, from 10 different traps. That's about four times higher than the average number of mosquitoes collected in past years by this time. Of the latest sample, officials estimate 26 percent tested positive for West Nile virus.

“Given the test results we are seeing, it may be more important now than ever to take steps to protect yourself and those who count on you from being bit,” London said. "Get out there and enjoy the outdoors and enjoy our Michigan summer. However, there are things that you can do that can significantly reduce your odds of getting bit by this mosquito."

There is no vaccine or cure for West Nile. The best treatment is prevention, and KCDH recommends the following:

  • Apply insect repellant that contains the active ingredient DEET and always follow the manufacturer’s directions for use
  • Drain standing water, empty water form flower pots, pet bowls, clogged rain gutters, buckets, barrels, and cans
  • Avoid being outside at dusk and dawn
  • Wear light colored long- sleeved shirts and long pants

Only 20 percent of people infected with West Nile virus exhibit symptoms, according to the CDC. One in 150 people develop severe illness that may damage the central nervous system.

"Everyone is vulnerable to West Nile virus, especially people over the age of 60," London said. "I'm very concerned that people will get hurt this year if they don't follow the precautionary measures we recommned."

For more information about West Nile virus and prevention, click here.

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