Mosquito bites are right up there with sunburn as one of the hassles of summer.
Fortunately, most mosquito bites usually produce some itching and a red, swollen mark that is gone in a few days. But for some bite victims, especially young children, a mosquito bite can be serious.
“La Crosse encephalitis (LAC) is a mosquito-borne disease that is endemic in western North Carolina,” said Brian Byrd, Ph.D., professor of environmental health sciences at Western Carolina University. Byrd is also supervisor of the Mosquito and Vector-Borne Infectious Disease Facility in the School of Health Sciences. “And while this disease is commonly found in western North Carolina counties and can affect anyone, it predominately affects children in the western part of the state.”
North Carolina reported the second highest number of LAC cases in the United States between 2012 and 2021. In addition, the North Carolina Department of Health and Human Services reports cases of West Nile virus and eastern equine encephalitis, two other mosquito-borne viruses, are also found in the state.
According to the Centers for Disease Control and Prevention (CDC), the symptoms of La Crosse encephalitis include a fever that lasts 2–3 days, headache, nausea, vomiting, fatigue and lethargy. But when the encephalitis sets in, and the brain starts to swell, symptoms include high fever, neck stiffness, disorientation, tremors and seizures.
While most patients fully recover, children can experience long-term effects of La Crosse encephalitis, including cognitive disorders and seizures.
The CDC reports most people who become infected with West Nile virus (WNV) experience no symptoms or a mild, flu-like illness. But in some cases, WNV can produce body aches, vomiting and a rash. In extremely rare cases, WNV can cause encephalitis, meningitis and possibly death.
Certain viruses develop and multiply inside a mosquito. The infected mosquito then transmits the virus through its saliva when it bites another, uninfected host. By passing on the virus, researchers say the mosquito acts as a “vector” of the disease.
Dr. Byrd has studied mosquitoes and the diseases they carry for years. His new focus is to work with children who were hospitalized due to LAC and determine what the lingering effects of the illness are after they’ve returned home.
“We plan to go to the houses and areas where children are getting infected and work to identify and reduce environmental factors,” adds Byrd. “There have been cases where a child gets sick, then the family moves out of the house, and years later a child in the new owner’s family also gets La Crosse encephalitis. It’s rare, but it is happening, and we want to understand why and identify modifiable risk factors at the house.”
Learn more about Dr. Byrd’s mosquito research by watching this Sci NC video.
It’s not just mosquitoes that bite and transmit diseases—ticks are also a problem. And like mosquitoes, most tick-borne diseases are reported between June and September.
“Ticks and mosquitoes are everywhere in North Carolina,” said Alexis M. Barbarin, Ph.D., state public health entomologist in a news release. “We encourage all North Carolinians to explore the outdoors but do so safely and take protective measures like using DEET or other EPA-approved repellants.”
Rocky Mountain spotted fever, Lyme disease and other tickborne diseases can cause fever, headache, rashes, flu-like illness and other symptoms that can be severe. Lyme disease accounts for more than half of the tick-borne diseases reported last year.
Ticks live in wooded, grassy, and brushy areas. If you’re in those areas, there’s a good chance you’ll encounter ticks and potentially be exposed to tick-borne disease.
