Rare Tick-Borne Bourbon Virus Diagnosed in Long Island Man

In May 2021, after spending days landscaping around his home in Shirley, Michael Larkin noticed two ticks on his thigh. Soon after, he suffered from debilitating headaches, a rash, high fevers, and night sweats, which ultimately led to a five-day hospitalization at Stony Brook University. Fortunately, he made a full recovery.

Fast forward to this month—five years later—and Larkin, now 67, learned the reason behind his illness. Doctors at Stony Brook informed him that he was the first confirmed case of Bourbon virus in New York, a rare tick-borne illness.

“I was really taken aback when I got a call last week. I didn’t realize it was so rare,” Larkin said during an interview at the Symposium on Tick-borne Disease held at Stony Brook’s Renaissance School of Medicine.

First identified in 2014 in Bourbon County, Kansas, the Bourbon virus can cause symptoms similar to other tick-borne diseases, including high fever, body aches, and vomiting. It spreads through the bite of a lone star tick, which is quite prevalent on Long Island.

Key Findings

• Larkin was informed this month that he had New York’s first known case of the Bourbon virus.
• Though there are few documented cases, doctors believe we might only be seeing “the tip of the iceberg.”
• Testing for Bourbon virus is not commercially available and must be conducted in specialized labs; no specific treatment or vaccine exists.

Currently, there is no targeted treatment for the Bourbon virus. Medical professionals mainly treat symptoms with intravenous fluids, antibiotics, and pain management.

In 2019, the Bourbon virus was detected in a tick found on another Long Island resident, but since the individual did not follow up, researchers could not confirm if they had been infected.

Confirmed cases have been exceedingly rare, leading health agencies to state that a “limited number” have been reported in southern and midwestern regions of the U.S. As of January, there were only six reported cases, according to a case study of a man who died from the virus in Kansas.

Experts suggest that the actual number of cases could be significantly higher.

Unlike more prevalent tick-borne illnesses such as Lyme disease, which can be tested for widely, Bourbon virus testing is limited to specialized facilities like the state Health Department’s Wadsworth Center, as noted by Dr. Luis Marcos, an infectious disease expert at Stony Brook Medicine.

Dr. Marcos conducted the research that confirmed Larkin’s diagnosis. He mentioned that the virus has been found in local ticks, indicating that other people may have had it, possibly recovering from mild symptoms without realizing they were infected.

“Patients are often diagnosed only when they are severely ill,” Marcos explained. “So we may only be seeing a fraction of the cases out there.”

Jorge Benach, a retired chair of the Department of Molecular Genetics and Microbiology at Stony Brook, praised the finding as “a very good piece of sleuthing work.” He suggested that the rising population of lone star ticks on Long Island could lead to an increase in Bourbon virus cases.

“The more you search, the more you’re likely to discover,” Benach remarked.

Rising Tick Population

Like many Long Islanders, Larkin recalls when finding a dog tick in the woods was uncommon, well before Suffolk County became a known hotspot for tick-borne illnesses such as Lyme disease and Alpha-gal syndrome, an allergy to red meat triggered by a tick bite.

“I can’t say I remember encountering many ticks back then,” he reflected.

When Larkin began feeling unwell, he quickly requested a Lyme disease test and a dose of doxycycline, a common antibiotic for Lyme. After four days without improvement, he ended up in the hospital.

“I was experiencing severe headaches, a high fever, and sweats,” he recounted. Tests for more common tick-borne diseases returned negative, but his liver enzymes were elevated. While in the hospital, Larkin received medication that eventually led to his recovery.

“It’s odd they couldn’t identify it then,” he mused. “I’m just glad I managed to get through it.”

While still hospitalized, Larkin met Dr. Marcos, who was conducting a long-term study on adults diagnosed with tick-borne illnesses presenting symptoms like fever and fatigue.

Between 2019 and 2024, over 200 participants enrolled in the study, though only 107 followed up. Blood samples were sent to the state Health Department for screening of three rare tick-borne viruses: Powassan, Heartland, and Bourbon.

“We see many patients who test negative for known tick-borne diseases,” Marcos said. “Without testing, we can’t grasp the virus’s true impact.”

There was evidence of a previous Bourbon virus infection in another study participant, but researchers could not trace when or where it occurred.

Now, Larkin is vigilant about tick checks and wears clothing treated with permethrin, which repels ticks. He even recently tested its efficacy.

“It still works,” he noted, “I put a live tick on it and watched it jump off.”