Seven-minute listen
Highlights
- In Florida, the tick species that spread the most diseases are the black-legged tick and the Lone Star tick.
- The most common tick-borne diseases in Florida are bacterial, with Lyme disease having the most cases.
- Alpha-gal syndrome is a growing concern. Caused by a Lone Star tick bite, it can trigger an allergy to red meat.
- Ticks are active year-round in Florida, especially north of Interstate 4. Different species peak in different seasons.
- Ticks are found in forests, parks and even urban green spaces.
- Using repellents, wearing protective clothing and performing thorough tick checks are essential to preventing bites and disease.
Imagine you’re taking a stroll through a wooded park after the rain has let up. It’s the first sunny day in a week of gloom and drizzle. You brush through some tall grass, unsuspecting of a tiny hitchhiker who just got a free meal. With a painless bite, a tick has latched on — and with it, the potential for hidden infectious diseases.
University of Florida Emerging Pathogens Institute member Greg Glass, Ph.D., broke down which ticks are most common in Florida, the diseases they can spread and how residents and visitors alike can stay safe.
Ticks of concern: More than just a nuisance
In Florida, two species of ticks stand out above the rest: The black-legged tick, also called the deer tick, and the Lone Star tick. These aggressive feeders target a variety of hosts. Less common ticks in Florida include the Gulf Coast tick, American dog tick, soft ticks and brown dog tick. The latter, as Glass points out, is particularly problematic.
“The (brown dog) ticks might prefer the dog (as a host), but they will feed on you,” Glass said. “So, if they happen to be carrying something like Rickettsia, they can transmit it to you. They crawl into crevices in the house and are really hard to find, and they’re really hard to get rid of once you get an infestation.”
Rickettsia is a genus of bacteria that causes diseases in humans, plants and animals. Notably, pathogenic Rickettsia species are responsible for serious illnesses in the typhus and spotted fever groups, with Rickettsia rickettsii being the cause of a dangerous disease, Rocky Mountain spotted fever.
Rocky Mountain spotted fever and two other diseases caused by Rickettsia species are three of the fifteen known diseases transmitted by ticks in the United States. Luckily, only a handful have been documented in Florida. While approximately 25 to 30 tick species are in the state, few pose significant health risks to humans.
According to the Florida Department of Health, the most common diseases from ticks in Florida are ehrlichiosis, Lyme disease, Rocky Mountain spotted fever and other spotted fever illnesses. These health threats fall into three broad categories: Viral, bacterial and immunological.
What to look out for in Florida
Ticks are effective carriers of arboviruses, but fewer than 10% of tick species are recognized as vectors of viruses, the first category of health threats. Fortunately, viruses account for a small portion of tick pathogenic spread, and there haven’t been any records of them documented in Florida.
“These are things like Powassan virus, Bourbon virus, which is one of my favorite ones, and Heartland virus,” said Glass, a UF professor emeritus of medical geography and vector-borne diseases.
Powassan virus is rare, with cases reported in the northeast and Great Lakes regions from late spring to mid-fall. Heartland virus and Bourbon virus present similar symptoms of fever, fatigue, rash, headache, body aches, nausea and gastrointestinal issues. There are currently no vaccines to treat tick-borne viral infections.
The second category of tick-borne health threats includes tick-borne bacterial and parasitic infections. These pathogens are more common here in the Sunshine State, with Lyme disease at the forefront.
“Lyme disease is the big one,” Glass said. “That has the most number of cases.”
Ehrlichiosis ranks second in the state and is the general term for bacterial infections caused by Ehrlichia chaffeensis, E. ewingii and E. muris eauclairensis. Following closely behind are spotted fever group Rickettsia, with Rocky Mountain spotted fever being the earliest identified. Other tick-borne bacterial diseases in Florida come from bacterial groups such as Anaplasma and Babesia. Southern tick-associated rash illness, or STARI, and tularemia share the spotlight with these bacterial groups.
The third category of tick-borne disease threats is from a lesser-understood immunological response known as Alpha-gal syndrome. This allergic reaction has achieved notoriety because of its unusual symptom. A bite from the Lone Star tick can trigger physical symptoms after eating red meat. Symptoms can emerge weeks or months after a bite, with some people’s bodies going into shock after eating red meat, while others notice little to no reaction.
“People don’t have Alpha-gal naturally, so that’s why you can develop an allergy to it, kind of like a bee sting,” Glass said. “In the tick bite, they actually inject Alpha-gal into you, and your immune system reacts to it.”
Factors like blood type and genetic makeup may play a role in susceptibility and severity of the reaction, but there are still more questions about Alpha-gal than answers.
Florida’s ever-changing tick landscape
Land use changes, such as the decline in cattle ranching and the resurgence of wildlife, are likely having a greater impact on tick populations than climate change. As Florida’s population expands and explores more wild spaces, ticks linger in tall grass and underbrush for unlucky visitors passing by. Forest edges, overgrown fields and even urban parks can harbor ticks.
Despite these risks, Florida does not face the same scale of tick-borne disease outbreaks as states in the northeast or upper Midwest. Confirmed Lyme disease cases remain concentrated in northern Florida. The cases remain relatively rare because its vector, black-legged ticks, prefers the northern part of the state.
Florida’s mild, moist climate keeps ticks active year-round, with different species peaking at different times. Lone Star and American dog ticks are more common in the spring and summer, while black-legged ticks tend to emerge in the cooler months.
“(Interstate 4) makes a pretty good demarcation,” Glass said. “North of I-4, not so good in terms of if you’re trying to get away from ticks. In the central part and south, ticks are less common. It’s harder to find them. They exist, but they’re not especially abundant.”
Ticks prefer damp, cool areas. The salt from beaches can dry them out, while the southern parts of the state are too hot. Beach towns usually lack many ticks because of the salty, dry air, but the tall grass on sand dunes is an exception.
“This is my conservation message — stay off the dunes,” Glass said.
Protecting yourself from tick bites
Tick-borne diseases can spread all over the world. Using a layered approach can significantly reduce your chances of tick encounters and keep you safer outdoors.
“The best way people can protect themselves is what we call a Swiss cheese defense,” Glass said. “The idea is that a block of Swiss cheese has holes in it, but the holes never go all the way through.”
These layers of defense include being aware of ticks in your area, using EPA-approved repellents, layering your clothing, and checking yourself and loved ones after outdoor adventures. After being outside, inspect the tops of your boots, waistband, crotch area, armpits and hairline. Take a shower, and do not wear the same clothes again until they are cleaned.
If you do find a tick, take a pair of tweezers, grip the tick where the mouth pierces the skin, and gently pull straight back. Glass notes that scotch tape and tweezers are your best friends.
“My favorite way of doing it is I use tweezers and scotch tape,” Glass said, “And what I do is I put the tick on the scotch tape, fold it over so it’s sandwiched in between. It’s stuck. It stays there and if I think I got sick from it, I have it to identify what the pathogen might be.”
Ultimately, Glass’s message is one of informed vigilance, not panic.
“I tend to tell folks to think about it kind of like defensive driving,” he said. “Doesn’t mean you anticipate you’re going to get an accident.”
For Floridians, ticks are a common part of the landscape, often found in the leaves we step on. Visiting a park should not be a cause for concern; a tiny bite can remain a minor problem as long as you’re vigilant.
Written by: Sydney Burge