Michigan officials reported eight new cases of Eastern equine encephalomyelitis across six counties this week, bringing the total number of cases to 29 in the state.
All eight horses confirmed positive had to be euthanized and were unvaccinated or undervaccinated.
Officials in Michigan and Indiana are concerned as a small outbreak of EEE hit the two states last year. They combined for 64 cases in horses and 11 in humans and with 36 cases in horses across the two states in 2020, some experts say the problem is here to stay.
“Historically high water tables caused by excessive rainfall and warmer than normal temperatures are creating conditions for mosquitoes to thrive,” Ned Walker, a mosquito expert at Michigan State University, told the South Bend Tribune. “Climate change is a factor as well as the maturation of suitable natural habitats.”
Additionally, 38 humans were infected with EEE in 2019, about the same number as the previous six years combined. Humans have about a 33 percent survival rate of EEE, unlike horses, which rarely survive the mosquito-borne illness.
The states have begun aerial spraying more than 800,000 acres in an effort to control mosquitoes that may be carrying the deadly virus.
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