Bad weather, resident concerns hamper Michigan’s efforts to spray for EEE virus

The Coquillettidia perturbans mosquito, also known as the cattail mosquito, is known as the “bridge vector” of deadly Eastern equine encephalitis because it transfers the virus from infected animals to humans. (Shutterstock image)

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A seemingly simple move against the deadly Eastern equine encephalitis virus — a statewide, airborne spraying campaign to kill mosquitoes that can the disease — is off to a slow start.

Weather has grounded the planes from the Illinois-based mosquito control company, Clarke, that were to carry pesticides. Rain renders the spraying less effective, and low cloud cover makes it difficult for pilots wearing military-grade night vision goggles to see, said Laura McGowan, Clarke spokeswoman.

Through Thursday afternoon, the state had sprayed 186,146 acres.

Meanwhile, resident concerns about chemicals sprayed overnight from low-flying aircraft has shrunk the target area from about 720,000 acres to 500,000 acres, said Lynn Sutfin, spokeswoman for the Michigan Department of Health and Human Services.

Residents are “concerned about their health,” said Leslie Kinnee, spokeswoman for the Mid-Michigan District Health Department.

“They’re concerned about their livestock. They’re concerned about their pets. They’re concerned ‘I still have vegetables in the garden. Will this pesticide be harmful to me?’” she said.

The health department, which covers Clinton, Gratiot and Montcalm counties, issued a notice to residents that were in areas to be sprayed after staff began fielding concerns. The notice instructed residents how to opt out of the program, but it also stressed the deadly nature of the EEE virus that this week killed a fourth Michigander. The victim lived in Calhoun County, according to the Michigan Department of Health and Human Services.

“I know people are concerned, we understand that,” Kinnee said. “But when you look at the facts, it’s a pretty nasty disease.”


On Sept. 27, the state announced plans to spray 720,000 acres hardest hit by EEE, which is rare in the U.S. but deadly, killing roughly 1-in-3 people who become ill. Even those who survive may suffer severe and permanent brain damage. Adults 50 and older and children are at greatest risk.

On average, the United States reports about seven fatal and non-fatal human cases each year for the entire country. But already this year, nine cases, including four fatalities, have been reported in Michigan’s Barry, Berrien, Calhoun, Cass, Kalamazoo and Van Buren counties. 

Additionally, EEE has killed horses, white tail deer, and two wolf pups in Barry, Berrien, Calhoun, Cass, Genesee, Jackson, Kalamazoo, Kent, Lapeer, Montcalm, Newaygo, St. Joseph and Van Buren.

Those cases and a prolonged warm spell prompted the state to launch its first scale spraying program since 1980. The state posts daily updates for residents on its Area Treatment Zones map.

The pesticide, Merus 3.0, is an organic pesticide containing 5 percent pyrethrin, a chemical found naturally in some chrysanthemum flowers but that is toxic to insects. 

The product lasts only a short time in the air. It dissolves as it hits the ground, eliminating concerns for bees because they’re not active until the morning, said Clarke spokeswoman McGowan.

The droplets settle to the ground within 30 minutes of spraying” and “immediately break down,” and Clarke pilots spray only until 3:30 a.m. or so, meaning the product has disappeared by the time bees emerge in the morning, she said.

But even as the state sought to reassure residents of the safety of Merus 3.0 and reported its fourth death from EEE , residents were concerned enough about chemicals that they have opted out of the spraying program.

Kalamazoo County, considered to be a high-risk area, had so many citizens requests to opt out of the program that it has withdrawn altogether from the spraying program, reducing the areas to be sprayed throughout the state by about 210,000 acres, according to Lynn Sutfin, spokeswoman for the state health department.

Among those concerned are Michigan’s bee keepers, who worry about the pesticides harm to honeybees.

The Great Lakes Bee Supply in Kalamazoo’s Galesburg recommended on its Facebook page that beekeepers pull their honey from hives early and provide clean water, specialized for honeybees, inside the hives.

Bees play a crucial role in the food chain, said owner Bill Graham, and beekeepers are already struggling to maintain hives against a shrinking bee population.

“I’m not trying to be ruthless,” Graham said, referring to the deaths from EEE. “But bees pollinate all our food all our vegetables, all our fruit, the crops for the cattle to eat, the pigs to eat — everything. We’re doing everything we can to get pollinators to make it, then they mass spray an area and could kill everything,” he said.

He said he did not lobby against the spraying, but that he recommended bee keepers close up the hives on the nights that the state sprays and throughout the following day.

The Michigan chapter of the Sierra Club, a national environmental advocacy group, has also fielded calls.

Chairwoman Anne Woiwode said it’s a difficult balance between those concerns and the human death toll. The chapter has advised its members to make their own decisions about spraying, sharing with them information on how to opt-out if that’s their decision.

Spraying was scheduled to continue Thursday night.

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Fri, 10/04/2019 - 11:32am

What is being sprayed equates to approximately ONE TABLESPOON of organic botanical mosquito insecticide PER ACRE. This is nowhere near enough to pose any adverse health effects to any human (or animal, aside from mosquitoes).

Also, the fatality rate for this arbovirus is about 30% in humans (90% in horses). 4 people have already died. I'll spend a few hours one night cooped up inside my home if it helps prevent more people from dying.

Linda Cook MacDonald
Fri, 10/04/2019 - 11:35am

For me, what I objected to is that the state - through local community health agencies - made the decision to spray without any pre-discussion that included the public. It is no wonder people responded the way they did. The other thing is this: "organic" in the case of Merus 3 does not mean "safe" or "not lethal". The ripple effect of the insecticide is not known - or if it is known - is not readily available to the public. Some of the warnings included this: if you have fish in a small garden pond, cover the pond. In other words - you don't want droplets going into the water as there will be an adverse effect.
When there is spraying of insecticide in the air, it is important for the public to be part of the discussion BEFORE the decision has been made. $1.8 million or thereabouts was used for this effort. How much better might it have been for a full scale public education and support campaign in the hardest hit areas and FREE topical insect repellents with excellent information on how to use the products. People are not buying what is necessary. Aerial spraying is "overkill" at the present time. People can do a lot to minimize their own risks but they need supportive programs that make self protection more widely followed.

middle of the mit
Sat, 10/05/2019 - 10:15pm

For the past couple of years I have been spraying my lots for not just mosquitoes but mostly for fleas and ticks. Bees aren't as susceptible because they don't live in the dead leaves on the ground. Mosquitoes, fleas and ticks do. Wait 'til spring. Then fluff up some of those leaves. When you see little things flying, those are baby mosquitoes.

The spraying didn't hurt me or my dog or my cat. It did cut down on population of fireflies though. That is why I gave this year a break. As far as garden ponds go? If you can cover your pond with a tarp, it is probably to protect your fish because there is not enough air to evaporate the toxin and not enough water to dilute it and your fish will die.

And for this conservative ideology of individuals protecting themselves with due diligence? Could you please let me know when that happens? They have never done it when it comes to anything. Climate, ecology, workers, economics, government.

People are NOT rational. They are individuals and conservatives have made sure of that. Therefore they only think about themselves and you CAN NOT TRUST THEM TO LOOK OUT FOR THE GREATER GOOD OF EVERYONE.

They will look out for their own economic and social gain and that is it.

Jesus used to a brownish hippy who told everyone to sell all they had, give the proceeds to the poor and follow him. Now he is a white guy with short hair and if you aren't made of money you aren't following his way.

Need I say more?

Erwin Haas
Fri, 10/04/2019 - 12:16pm

Got news for you buddy; mosquitoes have long since disappeared from W Michigan where my wife and I hike almost daily. Someone is paying the "sprayers" for "building bridges to nowhere" and this whole business should be investigated for the cash flows.

J. Katakowski
Fri, 10/04/2019 - 8:09pm

My simple comment is in regards to our bee population. I read the article and it says it is ok with the bees because they do not emerge until morning. I am not as trust worthy of government these days due to current practices. Bees need to be taken into consideration since they have lost a lot of their much needed population of late. Perhaps more information needed here.

Tim Hall
Fri, 10/04/2019 - 9:24pm

an earlier article had said that the pesticide needed to be washed off surfaces, leading me to believe that it would still be present after daylight, when the bees come out, along with other insects. now the article says the substance will "dissolve" (into what?) shortly after being sprayed in the middle of the night. what is the story here?

Debby W
Sun, 10/06/2019 - 8:36am

Bees do not go inside their hive when it is hot at night ( Monday and Tuesday when they sprayed Van Buren county) and especially now when their hives have been consolidated for winter. So no, they are not necessarily inside so the “spray doesn’t hurt them”. Also to me bees =hymenoptera, that includes bumble bees, wasps, and tiny native pollinators. I could go on but the bottom line is that this whole decision was misguided. The question to investigate is “why is EEE so Prevalent all the sudden in S W Michigan?” Mosquitos are just the carriers.

Mon, 10/07/2019 - 8:56am

We see cases of EEE in SW MI each year (in animals or humans). What is different about this year is the sheer number of cases (and deaths) we're seeing from EEE. Most likely due to high water levels and the fact that we haven't had a cold frost as of yet.