Residents should be diligent about mosquito control
The Michigan Department of Agriculture and Rural Development (MDARD) State Veterinarian Dr. James Averill confirmed West Nile Virus (WNV) in two horses last week—one in Kent County and one in Ingham County—and reminds owners to get their horses vaccinated against the disease. WNV is a mosquito-borne disease affecting both humans and animals causing influenza-like symptoms and hospitalization in infants and older people who may be weak from other illnesses.
“Horses can be sentinel animals for what is going on around us. If a horse is sick, you can be sure there is reason to be cautious,” Averill said. “Signs of WNV in horses may include stumbling, tremors, skin twitching, struggling to get up, and facial paralysis, difficulty passing urine, a high temperature, impaired vision, and seizures. This is a very serious illness, and horses may ultimately have to be euthanized.”
Since West Nile Virus is spread to horses through the bite of an infected mosquito, protection measures reducing exposure to mosquito bites should be adopted. Horse owners should follow these tips to prevent mosquito-borne illness:
1. Vaccinate. WNV vaccines are inexpensive and readily available. It is not too late.
2. Use approved insect repellants to protect horses and follow label instructions.
3. If possible, put horses in stables, stalls, or barns, preferably under fans.
4. Eliminate standing water and drain troughs, and large containers at least once a week.
As of September 9, 12 human cases of WNV had been reported in Michigan in various counties. Blood donor screening provides an important early warning of WNV activity. Most people who are infected with WNV do not develop an illness, but the virus might be temporarily present in their blood. Because people may not know they have been infected, all donated blood is screened and samples are reported as “probable” cases, pending follow-up and testing of the donors. Last year, 202 WNV human illnesses and 17 human fatalities were reported in Michigan.
In addition, birds from 46 out of Michigan’s 83 counties have been found dead and reported to have WNV. Five counties also identified WNV positive mosquito pools (Bay, Kent, Midland, Saginaw, and Tuscola) from 3,128 mosquito pools and 43,393 mosquitoes tested.
Michigan is screening for five arboviruses: West Nile Virus, St. Louis Encephalitis, Eastern Equine Encephalitis (EEE), LaCrosse Encephalitis , or Powassan. The only mosquito-borne viruses that appear to be active right now are EEE (reported in a Van Buren County horse last week) and WNV. See up to date info at www.michigan.gov/emergingdiseases.