The state’s first confirmed case of eastern equine encephalitis has been found in Barron County, according to an Aug. 2 press release from the Wisconsin Department of Agriculture, Trade & Consumer Protection.

The announcement was relayed by Laura Sauve, public health program manager and heath officer for the Barron County Department of Health & Human Services.

The 22-year-old quarter horse mare had not been vaccinated against EEE, and was euthanized after showing neurological signs and becoming unable to rise, according to Leeann Duwe, public information officer for the state agency.

EEE and West Nile virus (WNV) are transmitted by mosquitoes. They carry viruses which can affect the nervous system and may be fatal.

The Department of Agriculture, Trade & Consumer Protection encourages horse owners to vaccinate their horses against these viruses to prevent the disease symptoms and high levels of fatality associated with them. EEE is fatal in more than 90 percent of clinical cases in horses while WNV is fatal in 30 to 40 percent of the cases.

“Vaccinating horses against EEE and WNV is necessary to prevent the suffering that occurs once the horse contracts the virus,” Dr. Julie McGwin, DATCP equine program veterinarian, said.

“While the number of cases of EEE and WNV were down last year compared to the previous year, it is heartbreaking for all involved to see any animal suffer through deteriorating health conditions caused by these viruses.”

In 2018, Wisconsin had a total of two cases of EEE and three cases of WNV reported. In comparison, Wisconsin had a record 24 confirmed cases reported of each virus in 2017. There are currently no reports of WNV cases this year.

According to the Department of Agriculture, Trade & Consumer Protection, the virus is not contagious between horses. Humans may also be infected by WNV and EEE, but the viruses do not pass directly between people and horses. Mosquitoes carry the viruses from infected birds and the only route of transmission is from a mosquito bite.

Because the viruses follow mosquito populations, the threat varies depending on the weather but normally starts in mid- to late summer and remains until the first killing frost.

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