Michigan residents reminded to protect against mosquito bites

For Immediate Release: September 20, 2016

LANSING, Mich. – The Michigan Departments of Agriculture and Rural Development (MDARD) and Health and Human Services (MDHHS) are reminding residents to protect themselves from mosquito bites, even with autumn officially beginning this week.

West Nile Virus activity in Michigan has increased since late August.  Health officials have identified 22 confirmed and probable West Nile virus (WNV) human cases and five blood donors to date. Further, 17 corvids, 25 other avian species, and two deer have tested positive for WNV from 25 Michigan counties in both the Upper and Lower Peninsula. Positive mosquito pools have been detected from seven Michigan counties (Bay, Kent, Macomb, Oakland, Saginaw, Tuscola, Wayne).

MDHHS has also confirmed a human case of Eastern Equine Encephalitis (EEE) in an out of state resident who was likely exposed in southwest Michigan.  The individual was hospitalized, has since been released and is recovering. Eastern Equine Encephalitis is a serious zoonotic viral disease transmitted by mosquitoes. The virus mainly causes disease in horses but can also cause serious illness in people, poultry, and other animals such as deer and even dogs.

As of September 20, MDARD has identified two cases of EEE in horses. One was a four-month-old Standardbred filly in Clare County.  The second case was a 12-year-old Quarter horse from Menominee County. Neither horse, nor the filly’s mother, was vaccinated against EEE. Both affected horses have died.

“After a hot, dry summer, mosquitos can continue to thrive until the weather consistently drops into the lower temperatures,” said Dr. Eden Wells, chief medical executive with the MDHHS.  “Even in the early Fall, residents should use repellent according to label instructions and take extra care during peak mosquito-biting hours between dusk and dawn.”

Mosquito management is vital in the prevention of mosquito-borne illnesses that cause illness in both humans and in horses. Residents can stay healthy by using simple, effective strategies to protect themselves and their families by reading and following all repellant label directions. The following steps are recommended to avoid mosquito bites:

• Apply insect repellents that contain the active ingredient DEET, or other U.S.
• Environmental Protection Agency approved product to exposed skin or clothing, and always following the manufacturer’s directions for use.
• Wear long-sleeved shirts and long pants when outdoors.  Apply insect repellent to clothing to help prevent bites.
• Maintain window and door screening to help keep mosquitoes outside.
• Empty water from mosquito breeding sites around the home, such as buckets, unused kiddie pools, old tires or similar sites where mosquitoes lay eggs.
• Use nets and/or fans over outdoor eating areas.
• Bringing horses and pets indoors from early evening until after sunrise when mosquitoes are out in full force.

Most people who become infected with WNV will not develop any symptoms of illness. However, some become sick three to 15 days after exposure. About one-in-five infected persons will have mild illness with fever, and about one in 150 infected people will become severely ill.

Mild illness may include headache, fever, body aches, joint pain, vomiting diarrhea, or rash. Severe symptoms of WNV are associated with encephalitis or meningitis, and may include: include stiff neck, stupor, disorientation, coma, tremors, muscle weakness, convulsions and paralysis.  People 50 and older are more susceptible to severe WNV disease symptoms.

People can be infected with EEE from the bite of a mosquito carrying the virus. The disease is not spread by horse-to-horse or horse-to-human contact. In humans, signs of EEE include the sudden onset of fever, chills, body and joint aches. EEE infection can develop into severe encephalitis, resulting in headache, disorientation, tremors, seizures and paralysis. Permanent brain damage, coma and death may also occur in some cases.

Signs of EEE in horses can include stumbling and the inability to stand. Vaccines for horses to protect them from EEE and other mosquito-borne diseases are available and are effective for preventing disease. Horse owners should work with their veterinarian to make sure their animals are up-to-date on all vaccinations. It's not too late to vaccinate this year for diseases like EEE.

For more information and surveillance activity about WNV, visit www.michigan.gov/westnilevirus.

# # #