In an effort to prevent spread of Eastern Equine Encephalitis (EEE), the Michigan Department of Health and Human Services (MDHHS) has announced plans to conduct aerial mosquito control treatment in certain high-risk areas of Michigan.
Impacted counties include Barry, Clare, Ionia, Isabella, Jackson, Kent, Mecosta, Montcalm, Newaygo and Oakland. Additional areas may be selected for treatment if new human or animal cases occur outside of the currently identified zones.
Treatment is scheduled to occur starting the evening of Wednesday, Sept. 16. However, treatment can only take place under certain weather conditions, so the schedule may need to change.
As of Sept. 13, EEE has been confirmed in 22 horses in 10 counties in Michigan. Additional animal cases are under investigation. This is twice as many animal cases as the same time last year.
To date, no human cases have been identified. There is an EEE vaccine available for horses, but not for people.
In order to prevent the loss of life and protect public health, MDHHS has determined a targeted aerial treatment plan is necessary. When there are high rates of animal infections, humans are just as at risk.
EEE is one of the most dangerous mosquito-borne diseases in the United States, with a 33-percent fatality rate in people who become ill. People can be infected with EEE from one bite of a mosquito carrying the virus. Persons younger than age 15 and over age 50 are at greatest risk of severe disease following infection. More than 25 percent of the nation’s EEE cases last year were diagnosed in Michigan.
“We are taking this step in an effort to protect the health and safety of Michiganders in areas of the state where we know mosquitoes are carrying this potentially deadly disease,” said Dr. Joneigh Khaldun, MDHHS chief medical executive and chief deputy for health. “As people are spending more time outdoors because of COVID-19, they also need to be protecting themselves from mosquito bites.”
Signs of EEE infection include the sudden onset of fever, chills, body and joint aches which can progress to a severe encephalitis, resulting in headache, disorientation, tremors, seizures and paralysis. Anyone who thinks they may be experiencing these symptoms should contact a medical provider. Permanent brain damage, coma and death may also occur in some cases.
The Michigan Department of Agricultural and Rural Development (MDARD) has issued an emergency rule temporarily amending the rule on notification and participation for community pesticide applications for aerial spraying treatment across affected counties. This means mosquito control treatment will be required for those areas that are identified by the aerial treatment plan with exception of federal properties and tribal lands.
Treatment will be conducted using Merus 3.0, the same product used in 2019. Merus 3.0 is registered with the U.S. Environmental Protection Agency and MDARD, and is labeled for public health use over residential areas. It contains 5 percent pyrethrins, a botanical insecticide extracted from chrysanthemum flowers. Pyrethrins are commonly used to control mosquitoes, fleas, flies, moths, ants and many other pests, and are approved for use in organic agriculture as well.
In general, health risks are not expected during or after spraying. No special precautions are recommended; however, residents and individuals who have known sensitivities to pyrethrins can reduce potential for exposure by staying indoors during treatment. Aerial treatment is not expected to have any impacts on surface water or drinking water.
To reduce the potential for people to be bitten by mosquitoes, MDHHS is continuing to encourage local officials in the affected counties to consider postponing, rescheduling or canceling outdoor activities occurring at or after dusk, particularly activities involving children until the first hard frost of the year.
How to protect yourself from mosquito bites:
• Avoid being outdoors from dusk to dawn when mosquitoes carrying the EEE virus are most active.
• Apply insect repellents containing the active ingredient DEET, or other EPA-approved product to exposed skin or clothing.
• 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.
• Use nets and/or fans over outdoor eating areas.
MDHHS hotline for general questions about both COVID-19 and EEE is 1-888-535-6136. The hotline is open from 8 a.m. to 5 p.m., Monday through Friday.