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Eastern Equine Encephalitis outbreaks in the United States

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2026-08-20 02:08 UTC → 2026-09-03 19:09 UTC · added ~~removed~~

Eastern Equine Encephalitis (EEE) activity has been reported across several U.S. states. Initially, Florida confirmed five equine cases in various counties, including Hillsborough, Jackson, Osceola, Seminole, and Volusia. While horses do not transmit the virus to humans, these cases serve as an early warning that local mosquitoes are carrying the disease. Following the reports in Florida, health officials in Massachusetts and Michigan also detected the virus. In Massachusetts, the virus was found in mosquito samples in Plymouth County, raising the risk level to moderate for several nearby communities. In Michigan, authorities confirmed the first locally acquired human case since 2021 in Roscommon County. Officials noted that the disease carries a “30% fatality rate among those who become ill.” In Florida, the number of confirmed equine cases has since risen to seven. The most recent case involved a horse in Washington County that had to be euthanized. Health officials emphasize that while horses do not develop high enough viral levels to be contagious to humans or other animals, the disease maintains a high mortality rate for both species.

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