Michigan will spray in 14 counties to fight deadly mosquito virus

Associated Press

Lansing — Michigan and local health departments will conduct aerial spraying for the first time since 1980 to combat a rare mosquito-borne virus that has killed three people and been recorded across the southern half of the state.

The aerial spraying is set to begin Sunday and will include 14 counties, including 13 where eastern equine encephalitis has been confirmed in humans or animals. Weather might determine the actual spraying schedule.

Spraying will occur in Allegan, Barry, Berrien, Branch, Calhoun, Cass, Jackson, Kalamazoo, Kent, Lapeer, Montcalm, Newaygo, St. Joseph and Van Buren counties. 

The virus has been confirmed in nine people, with three fatalities, in six counties in southwestern Michigan. There have been 27 animal cases in 13 counties.

Other states, including Massachusetts and Rhode Island, have recently done aerial sprays.

In announcing the move Friday, Michigan officials cited the large geographic distribution and number of cases along with warm weather projections. Mosquitoes generally do not die until the first hard frost.

“We believe that this is another tool that we can use to protect health,” said Dr. Joneigh Khaldun, the state’s chief medical executive.

Officials said low-flying planes will spray an organic pesticide over 720,000 acres, at an estimated cost of between $1.5 million and $1.8 million.

The state last sprayed mosquitoes in 1980, though communities have sprayed locally to fight outbreaks of the West Nile virus and to control mosquitoes as a nuisance, said Dr. Mary Grace Stobierski, the state’s public health veterinarian.

Officials said the pesticide, Merus 3.0, will not pose a health risk to humans or animals, including bees and other pollinators such as butterflies.

Michigan is encouraging officials in affected counties to consider postponing or rescheduling evening outdoor events until there is a hard frost.

At least a dozen southwest Michigan school districts decided a week ago to reschedule high school football games to reduce exposure to mosquitos because of concerns about the outbreak of the mosquito-borne virus, MLive reported. 

The pesticide being used is Merus 3.0, an organic pesticide containing 5% pyrethrin, chemicals found naturally in some chrysanthemum flowers. They are a mixture of six chemicals that are toxic to insects and are commonly used to control mosquitoes, fleas, flies, moths, ants and many other pests. Pyrethrins have been registered for use in pesticides since the 1950s.

The number of U.S. deaths and illnesses from the virus are higher than usual this year.

U.S. Rep. Fred Upton, R-St. Joseph, sent a letter to the Center for Disease Control and Prevention requesting information about the CDC’s efforts to prevent the spread of the disease.

“Given the record numbers of EEE cases in Michigan and other at-risk states, we would appreciate the opportunity to learn more about the CDC’s efforts to prevent the spread of this vector borne illness," Upton wrote in the Friday letter. "I would also like to learn of any effort to develop treatments for those who have already contracted this disease."

The Detroit News contributed.