Rare tick-borne illness making headway in Virginia

CHESTERFIELD COUNTY, Va. (WRIC) -- As summer calls us outdoors, a crucial health warning emerges from medical experts. While Lyme disease often grabs headlines, a lesser-known but increasingly concerning tick-borne illness, babesiosis, is making its presence felt in Virginia.

Babesiosis is caused by a tiny parasite carried by the blacklegged tick or "deer tick" — the same ticks notorious for transmitting Lyme disease.

"It is certainly becoming a significant problem here in Virginia," said Dr. Marconi, a professor in the Department of Microbiology and Immunology in the VCU School of Medicine.

The Virginia Department of Health reports only 17 confirmed cases of babesiosis originating in Virginia since 2016, with most found on the Eastern Shore or in Southwest Virginia.

VDH said it's interesting to note a shift in babesiosis cases, both acquired within and outside of Virginia, starting in 2021. That year, out of 11 cases, the majority (10) were from Virginia residents who had acquired the disease while traveling outside the state.

While 2022 still saw a significant number of cases, the trend began to shift towards more locally-acquired infections, with 4 local cases compared to 7 travel-associated ones.

However, 2023 truly caught VDH's attention. In that year, the majority of cases reported were locally-acquired, totaling 7 cases. This three-year period clearly shows a change in where Virginia residents are contracting babesiosis, indicating that Babesia microti -- the agent transmitted by the blacklegged tick -- is making headway in Virginia.

One of the challenges with babesiosis is that many cases go undiagnosed.

"The majority of cases will be asymptomatic," Dr. Marconi explained. "So an individual may not even know that they have the infection." This makes pinpointing actual case numbers difficult.

However, for those who do experience symptoms, they can range from mild, including fever, chills, muscle aches (myalgia), fatigue, and anemia. But in others, the disease can progress to a very serious, even fatal, condition.

Dr. Marconi warned, "The fatality rate can be as high as 5% in healthy individuals, whereas in individuals that are immunocompromised, that can be as high as 21%.

Nationwide, babesiosis cases have been steadily climbing, with a 9% increase each year from 2015 to 2022. Dr. Marconi emphasized that while we see babesiosis in a wide range of the population, tick exposure — often linked to outdoor activities like gardening, hiking, and landscaping — is the primary method of transmission.

The majority of babesiosis infections are spread by nymphal or adult-stage ticks.

"Larvae, when they emerge from the egg, are not infected. The only way they can become infected is by feeding on an infected animal, which is typically wildlife," Dr. Marconi said.

A significant concern, Dr. Marconi added, is that four out of ten people who contract babesiosis will likely also be infected with Lyme disease. This co-infection of multiple pathogens simultaneously makes diagnosis significantly more difficult.

With roughly 20,000 babesiosis cases reported nationwide between 2018 and 2022, and numbers continuing to increase, vigilance is paramount.

Here's how to protect yourself and your loved ones:

• Wear long sleeves and pants when outdoors, especially in wooded or grassy areas.
• Use EPA-approved tick repellents as directed.
• Perform thorough tick checks on yourself, your children, and your pets after spending time outdoors.

While there are about 100 different species of Babesia, only a few are of importance to human infections. Dr. Marconi is actively working on new, rapid screening tests for babesiosis, which could allow for earlier detection and better outcomes.