More Than Just an Annoyance
For most Florida residents, mosquitoes are an everyday nuisance. But these small insects carry diseases that pose real health risks, and the Tampa Bay area's warm, humid climate makes it one of the most active mosquito regions in the United States. Florida is home to over 80 species of mosquitoes, and several of them are capable of transmitting serious illnesses to humans.
The good news is that mosquito-borne illness is largely preventable. Very few bites lead to disease, and the same handful of habits — repellent, source reduction, and knowing the warning signs — dramatically lowers your risk. At Zimmer Medical Group, we want our patients to enjoy St. Pete's outdoor lifestyle year-round while understanding how to minimize their exposure to mosquito-borne disease.
Which Mosquito-Borne Diseases Show Up in Florida
Not every mosquito carries disease, and most bites result in nothing more than an itchy welt. Still, it helps to know which illnesses circulate along the Gulf Coast so you can recognize the symptoms early.
West Nile Virus
West Nile virus is the most common mosquito-borne illness in the continental United States. Most infected people (about 80 percent) show no symptoms. Roughly 20 percent develop West Nile fever with symptoms including headache, body aches, joint pain, vomiting, diarrhea, and rash. In rare cases (less than 1 percent), the virus can cause severe neurological illness including encephalitis or meningitis.
Dengue Fever
Dengue has re-emerged in Florida in recent years, with locally acquired cases reported in several counties. Symptoms include high fever, severe headache, pain behind the eyes, joint and muscle pain, and rash. Severe dengue can cause hemorrhagic fever and requires immediate medical attention.
Zika Virus
While Zika transmission has decreased significantly since the 2016 outbreak, the mosquitoes that carry it remain in Florida. Zika is particularly dangerous during pregnancy, as it can cause severe birth defects. The Centers for Disease Control and Prevention advises that people who are pregnant or trying to conceive take extra precautions to avoid mosquito bites.
Eastern Equine Encephalitis (EEE)
EEE is rare but extremely serious, with a fatality rate of approximately 30 percent in those who develop symptomatic infection. Florida typically reports the most EEE cases of any state. While human cases are uncommon, the severity of the disease makes prevention essential.
Chikungunya
Chikungunya causes fever and severe joint pain that can last for weeks or months. While most cases in Florida are travel-related, local transmission has occurred and remains possible.
Mosquitoes are not the only biting insect worth watching locally. For a closer look at how these viruses circulate in our own backyard, see our overview of mosquito-borne illness across Pinellas County, and for a different vector entirely, our guide to tick-borne illness and alpha-gal syndrome.
When Mosquitoes Are Most Active in Tampa Bay
In the Tampa Bay area, mosquito season essentially runs year-round, with peak activity from May through October. Mosquitoes are most active during dawn and dusk, though the Aedes mosquitoes that carry dengue and Zika bite aggressively during daylight hours as well — which is why "I only go out during the day" is not a reliable defense here.
Activity increases significantly after rain, as standing water provides breeding habitat. Even small amounts of water in flower pots, bird baths, gutters, and discarded containers can produce hundreds of mosquitoes. Our summer downpours and tropical systems make this worse: the days after a heavy rain or storm are often the buggiest of the year. Clearing standing water is one of the small storm-recovery tasks worth adding to your routine, right alongside the other steps in our hurricane season health preparedness guide.
Effective Prevention Strategies
Use EPA-Registered Insect Repellents
The CDC recommends EPA-registered insect repellents, which have been evaluated for both safety and effectiveness. Look for one of these active ingredients:
- DEET (20-30%): The long-standing gold standard, effective for several hours per application. Safe for adults and children over two months old when used as directed.
- Picaridin (20%): Comparable effectiveness to DEET without the greasy feel or odor. A popular choice for daily use.
- Oil of Lemon Eucalyptus (OLE/PMD): A plant-based option with good efficacy. Not recommended for children under three years old.
- IR3535: Another effective option available in various formulations.
Natural repellents such as citronella, lavender, and tea tree oil provide some protection but are significantly less effective and shorter-lasting than EPA-registered products.
How to Apply Repellent Correctly
Even the best repellent only works when it is used properly. A few CDC-backed habits make a real difference:
- Apply to exposed skin and clothing only — never underneath clothing.
- Don't spray your face directly. Spray your hands first, then pat it onto your face, avoiding the eyes and mouth.
- Put sunscreen on first, then repellent when you need both.
- Avoid broken skin, cuts, and irritated areas.
- For children, apply it to your own hands and then onto the child; do not let young children apply it themselves, and keep it off their hands, which often end up in their mouths.
- Reapply as directed on the product label, and wash it off with soap and water once you are back indoors.
Eliminate Standing Water Around Your Home
Mosquitoes can breed in as little as a bottle cap of water. Regularly inspect your property for:
- Clogged gutters and downspouts
- Old tires, buckets, and containers that collect rainwater
- Bird baths (change water at least weekly)
- Flower pot saucers
- Pool covers that accumulate water
- Pet water bowls (refresh daily)
- Garbage cans without tight-fitting lids
Dress Defensively
When spending extended time outdoors during peak mosquito hours:
- Wear long sleeves and long pants when practical
- Choose light-colored clothing, which is less attractive to mosquitoes
- Treat clothing with permethrin, an insecticide that repels and kills mosquitoes on contact and remains effective through several washings
Protect Your Home
- Ensure all window and door screens are intact and free of holes
- Use air conditioning when possible, as mosquitoes avoid cool environments
- Consider using mosquito nets over beds if screens are not available
A Pinellas County Yard-and-Patio Checklist
Life on the peninsula comes with a few very local mosquito traps that are easy to overlook. Walking your property once a week during the rainy season — a habit sometimes called "tip and toss" — is the single most effective thing you can do to keep the population down close to home:
- Screened lanais and pool cages are wonderful until a screen tears. A single gap lets in daytime-biting Aedes, so patch holes promptly.
- Bromeliads and other tropical plantings hold water in their leaf cups, making them quiet little breeding sites. Flush them with a hose midweek.
- Boat covers, kayak wells, and dinghies collect rainwater; drain them after every storm.
- Rain barrels should be screened, and AC condensate lines, saucers under potted plants, and clogged gutters all deserve a look.
- Report persistent problems. Pinellas County residents can contact county mosquito control to report heavy mosquito activity or request assistance — a resource many locals do not realize they have.
Neighbors matter here, too: mosquitoes rarely respect property lines, so a coordinated block that tips out standing water together sees far fewer bites than any one household acting alone.
Myths vs. Facts
- Myth: Mosquitoes are drawn to people with "sweet blood." Fact: Attraction is driven mostly by the carbon dioxide you exhale, your body heat, and your natural skin chemistry — not by sugar in your blood.
- Myth: Eating garlic or taking a vitamin B1 supplement will keep mosquitoes away. Fact: There is no reliable evidence for these home remedies. EPA-registered repellents are what actually work.
- Myth: A backyard bug zapper solves the problem. Fact: Zappers mostly kill harmless, non-biting insects. Removing standing water and using repellent protect you far more.
- Myth: You only need repellent at dusk. Fact: The Aedes mosquitoes that can carry dengue and Zika bite during the day.
- Myth: If I don't feel sick after a bite, I'm in the clear. Fact: Most West Nile infections cause no symptoms at all. Stay alert for fever or other warning signs for up to two weeks after exposure.
Frequently Asked Questions
Does a higher percentage of DEET work better?
A higher concentration lasts longer between applications; it does not make the repellent "stronger." For most everyday outings, a product in the 20-30 percent range provides ample protection when reapplied as directed.
Do citronella candles and clip-on foggers really work?
They may offer modest, very localized help in still air, but a light breeze or moving around your yard quickly undercuts them. Treat these as a minor supplement, not a substitute for repellent on your skin.
Are "natural" repellents a safe alternative?
Some are genuinely effective — oil of lemon eucalyptus (OLE/PMD) is EPA-registered and works well, though it should not be used on children under three. Many other essential oils offer only brief, unreliable protection because they evaporate quickly.
Can my pets catch anything from mosquitoes?
Mosquitoes transmit heartworm to dogs and cats, which is a serious and preventable disease. Ask your veterinarian about year-round heartworm prevention, especially given our long Florida mosquito season.
When to See Your Doctor
Most mosquito bites cause only minor itching and swelling. However, seek medical attention if you develop any of the following symptoms within two weeks of mosquito exposure:
- Fever of 101 degrees Fahrenheit or higher
- Severe headache, especially with neck stiffness
- Joint or muscle pain that seems disproportionate to normal activity
- Rash
- Nausea, vomiting, or diarrhea
- Eye pain or pain behind the eyes
- Confusion or altered mental status
These symptoms may indicate a mosquito-borne infection that requires medical evaluation. Most mosquito-borne illnesses are diagnosed through blood tests and managed supportively, but early recognition is important, particularly for severe forms of the disease. If you are unsure whether a fever and body aches warrant a same-day visit, our guide to choosing between urgent care, the ER, and your primary doctor can help — and as a concierge practice, we would always rather you call and ask.
Special Considerations
Pregnant Women
Take extra precautions to avoid mosquito bites throughout pregnancy. Discuss Zika prevention with your healthcare provider, especially if traveling to areas with active transmission. EPA-registered repellents are considered safe to use during pregnancy when applied as directed.
Older Adults
Seniors are at higher risk for severe outcomes from West Nile virus and EEE. Consistent use of repellents and limiting outdoor exposure during peak mosquito hours is especially important.
Immunocompromised Individuals
Patients with weakened immune systems should be particularly vigilant about mosquito prevention and report any fever or unusual symptoms promptly.
Travelers
If you are heading to the Caribbean, Central or South America, or other regions with active dengue, Zika, or chikungunya transmission, pack repellent and plan to use it consistently. Many local cases in Florida begin as infections acquired abroad, so protecting yourself while traveling protects our community when you return.
Concerned about a possible mosquito-borne illness? Contact Zimmer Medical Group to schedule an evaluation. Early recognition and treatment lead to the best outcomes.
