Spraying to battle Triple E set to begin this week

Portions of 10 counties to be sprayed
EEE, Mosquitoes
Posted at 5:47 PM, Sep 14, 2020
and last updated 2020-09-14 18:39:18-04

GRAND RAPIDS, Mich. — In 2019, Michigan had more human cases of Eastern Equine Encephalitis than the previous decade combined with ten cases and six fatalities.

To date, the state is reporting no human cases so far this year, but the dangerous infection has been found in horses in ten different Michigan counties since late July.

Dr. Joneigh Khaldoun, Michigan's Chief Deputy Director for Health and Human Services, issued a warning Monday, explaining the need for spraying to combat mosquitos.

“This year, while we’ve not identified any human cases yet, the number of animal cases to date is twice what we had last year at the same time. What we know this means is that the mosquito is active and humans are at risk of getting the disease as well,” Dr. Khaldoun explained over a conference phone call Monday.

22 cases in horses are all believed to be fatal, and include one case in Kent County, one in Barry County, two in Newaygo County and seven in Montcalm County, so the state will begin spraying approximately 290,000 acres starting Wednesday night for at-least three days, possibly up to five, depending on the weather.

Dr. Sara Lyon-Callo, a State Epidemiologist with the MDHHS explained, “Aerial treatment can quickly reduce the number of mosquitos in a large geographic area, which in turn can reduce the risk of exposure to Triple E to humans.”

Dr. Lyon-Callo explained that planes will disperse “very fine aerosolized droplets, smaller than the head of a pin. They drift through the air column to kill adult mosquitos on contact.”

The product they will be using is the same as last-year, Merus 3.0, which is partially made from chrysanthemums, according to Dr. Lyon-Callo.

But unlike last year, residents are not able to opt out of having their neighborhood sprayed. “The serious nature of Triple E and the risk to human health, the Michigan Department of Agriculture and rural development in constitution with the MDHHS found it necessary and appropriate to temporarily amend the rule on notification and participation for community pesticide applications for mosquito control," Dr. Lyon-Callo said. "Notifications and exclusion requirements are waved as the MDHHS Director has determined a waiver is necessary to protect public health.”

For more information about the spraying, or to check out the planned spray map, go to