The Washtenaw County Health Department has encouraged residents to take extra caution in preventing mosquito bites in September since testing has revealed an increased presence of the West Nile Virus in several mosquitoes and birds around Ypsilanti.
Susan Ringler-Cerniglia, communications and community health promotion advisor for the Washtenaw County Health Department, said residents particularly need to take precautions during late August and early September.
“When we see human cases, it's almost always [in] the weeks right before and right after Labor Day. So just because of the way the virus cycle works in the animals, it's when we tend to see infections, so we like to make sure people know at this time of year,” Ringler-Cerniglia said.
West Nile Virus is a mosquito-borne illness that can cause flu-like symptoms. The most common symptoms are fever (dubbed the West Nile Fever), body aches and swollen lymph nodes.
In severe cases, illnesses such as meningitis and encephalitis can occur, though those are extremely rare, she said.
Specimen collection by the Washtenaw County Health Department and analysis by the Michigan Department of Health and Human Services has detected West Nile in six mosquito pools in Washtenaw County. Three of those pools were specifically found in Ypsilanti around the southwestern part of the county. Additionally, testing has identified three deceased bird specimens as holding the virus.
Those numbers are increases from three mosquito pools and zero bird cases in 2023.
While a definitive reason for the increase remains unknown, Ringler-Cerniglia said it could be due to the hot weather temperatures present in the county this summer.
“A lot of it has to do with the weather and the type of mosquitoes that like that,” Ringler-Cerniglia said. “They typically like hot, dry weather, and of course, it hasn't been especially dry, but it has been hot."
While increased activity might be a cause for concern, Ringler-Cerniglia said serious illness is rare. According to the U.S. Centers for Disease Control and Prevention, 80% of those infected with West Nile never experience symptoms. Moreover, Washtenaw County has not had a human case of West Nile since 2018.
“It's not something that we're looking to really have people feel anxious about or to avoid the outdoors or anything like that,” Ringler-Cerniglia said. “But it is a bit more positive activity than we’ve seen in birds and mosquitoes in several years.”
Regarding non-human cases, Ringler-Cerniglia said West Nile is not a known threat to pets. Though it has been found in birds, the only recorded Washtenaw County cases are in crows, bluejays and ravens. Typically, domestic pets, such as birds, dogs and cats, have a very low chance of contracting the virus, and those that do fully recover.
To prevent mosquito bites, Ringler-Cerniglia and the Washtenaw County Health Department encourage those participating in outdoor activities to apply bug spray, wear light-colored and long-sleeve clothing, and close any open windows.
“Nobody likes to get bit by mosquitoes anyhow. So, you know, this is the time of year, that late summer, when there's potential for more infection. So, take a few extra precautions to avoid mosquito bites, and it is not likely you have to worry about it,” Ringler-Cerniglia said.
The health department also recommends that residents dump out any standing water they have on their property on a weekly basis. Things like kiddie pools, outdoor water bowls for pets, and bird fountains may make the perfect breeding ground for mosquito eggs. Removing standing water will not only prevent the birth of new mosquitos, but will also keep pets safe from heightened exposure when venturing outside.
While the increased West Nile activity in the county is something to be conscious of, the Washtenaw County Health Department said it should not change on any late summer or early fall outdoor plans.
