Even as temperatures drop, risks for mosquito-borne illness remain high

 

SOUTH BEND, Ind.--- Eastern Equine Encephalitis (EEE) causes inflammation of the brain and spinal cord. This year, there have been two cases in LaGrange County, one in Kosciusko County, and one in St. Joseph County, Michigan.

The virus can only be spread through mosquito bites, which is why health officials say it is crucial to keep horses up-to-date on vaccinations. But it’s also good practice to avoid mosquitos in general, because while transmission to humans is rare, it can be very consequential.

“The mosquitos are still out, and with the infection rates being what they are, there’s not too many mosquitos out, but those that are still out are carrying diseases with more frequency,” said Brett Davis, the assistant director of environmental health for the St. Joseph County Department of Health.

The horse morbidity rate, according to the American Association of Equine Practitioners, is between 75 and 95 percent.

Luckily, though, an infected horse or human is not contagious.

The Cleveland Clinic reports that one in three humans who contract the virus die, but only five percent of those bitten by EEE-carrying mosquitos get the virus.

“It does seem to be occurring with a little more frequency than it used to,” Davis said.

Here in Michiana, a 2019 outbreak of EEE resulted in one human death in Elkhart County, according to Davis. This was followed by another outbreak in 2020.

“That really kind of reinvigorated the vector control efforts in the county,” he said.

Although temperatures are dropping, Davis said Hoosiers are not in the clear until there is a hard freeze, or a prolonged temperature of around 28 degrees.

Davis warns it’s still possible, this late in the year, to contract a mosquito-borne disease, like EEE or the West Nile virus.

“The risk for EEE is low right now, however, the risk for West Nile virus still remains high,” Davis said. “So even though EEE is not the threat it was in year’s past, people do still need to be wearing repellent and being conscious of being out in mosquito-prone areas at dusk.”

In horses, the onset of symptoms can be abrupt. These include depression, anorexia, fever, and neurological symptoms. Davis said to get a sick animal tested by a veterinarian.

In humans, while asymptomatic cases exist, Davis said it typically manifests with flu-like symptoms.

“So if you are experiencing flu-like symptoms, and it’s not improving, contact your primary care physician and get yourself checked out,” Davis said.

Luckily, Davis said out of 15,000 mosquitos tested in St. Joseph County this year, the EEE are low.

Still, continue to wear repellent with one of these CDC-approved ingredients: DEET, picaridin (known as KBR 3023 and icaridin outside the US), IR3535, oil of lemon eucalyptus (OLE), para-menthane-diol (PMD), or 2-undecanone