The car is packed, the condo is booked, and the Canadian winter is finally someone else's problem. If the Tampa area is on your map this year, there is one more thing to pack, which is mosquito repellent and a working knowledge of a virus most Canadians have never had to think about.
Florida is in the middle of its largest dengue outbreak in decades, with most cases in Hillsborough County, home to Tampa, the Associated Press reported in October. Nearly 500 locally acquired cases, meaning people infected in Florida rather than abroad, had been reported in the state by early November, Tampa public radio station WUSF reports. The outbreak was also linked to the death of an 80-year-old Tampa woman in September, and University of Florida insect scientist Eva Buckner told WUSF she had never seen anything like it.
Key takeaways
Florida's outbreak is centred on Hillsborough County, where officials declared local emergencies and crews sprayed day and night.
Nearly 500 people had caught the virus inside Florida by early November, according to WUSF.
The mosquitoes that spread it bite mostly during the day, so an evening bug spray routine is not enough on its own.
About 200 to 300 Canadians bring the infection home from trips each year, and none has caught it from a mosquito in Canada.
A fever during your trip or in the two weeks after you get home deserves a visit to a health care provider.
Why did a tropical virus take hold around Tampa?
Dengue is a tropical virus spread by Aedes mosquitoes, and people usually catch it while travelling in parts of South America, Asia, or Africa where it circulates all year. This year, WUSF explains, the virus was unusually active worldwide, which brought more infected travellers into Florida, where local mosquitoes picked it up and passed it on.
The weather played its part as well. Buckner told WUSF that the Aedes aegypti mosquito lays drought-resistant eggs, so a long dry spell let them pile up until the June rains hatched them all at once, just in time for a hot, humid summer. Local spread in Florida usually clusters around Miami, and Hillsborough officials told WUSF they were less prepared for a tropical disease than counties farther south.
There is some encouraging news. Weekly cases have started to slow as cooler, drier air moves in, according to WUSF, though the dengue outbreak has not ended.
What should Canadian snowbirds know before they fly?
Canadian snowbirds have little reason to recognize this illness, because it does not spread from mosquitoes at home. According to the National Collaborating Centre for Infectious Diseases, every case reported in Canada has been in a traveller returning from a place where the virus circulates, with about 200 to 300 cases a year.
It usually starts with a sudden high fever, a severe headache, and intense muscle and joint pain, which can feel like a very bad flu. Most people recover within about a week, yet a small share develop severe illness with bleeding and dangerously low blood pressure, which is why the warning signs matter. Our report on why mosquito season still had not ended in November explains the insects closer to home.
How do you avoid daytime mosquito bites?
Protection is mostly about preventing mosquito bites, and the Aedes mosquitoes behind this dengue outbreak are daytime biters that breed in small pools of standing water. The Government of Canada's travel health page recommends the same basic habits for anyone heading to an area where the virus circulates.
Use repellent during the day. Choose one with DEET or icaridin and apply it to exposed skin in the morning and afternoon as well as at dusk.
Cover up when you can. Light, loose long sleeves and long pants make it harder for mosquitoes to find skin.
Pick a place with screens or air conditioning. Intact window screens and closed, air-conditioned rooms keep mosquitoes out while you sleep.
Tip out standing water. Empty plant saucers, buckets, and pool covers at your rental, since mosquitoes breed in very small amounts of water.
Check your travel medical insurance. Confirm the policy covers your whole stay and read the pre-existing condition rules, which our report on the fine print behind a large travel medical bill walks through.
When does a fever after your trip need a doctor?
A fever after your trip, or one that starts while you are away, is worth a visit to a health care provider, and it helps to say exactly where you travelled, since this illness can look a lot like the flu. Canada's National Collaborating Centre for Infectious Diseases notes that acetaminophen is often used for the fever and pain, while aspirin and ibuprofen are not recommended because they can raise the risk of bleeding.
Go to an emergency department right away for severe stomach pain, repeated vomiting, bleeding from the gums or nose, blood in vomit or stool, or unusual drowsiness or restlessness. Our guide to the health risks Canadians face when travelling covers what else to sort out before you leave.
Frequently asked questions
Can you catch it from mosquitoes in Canada?
No local spread has ever been reported in Canada, according to the National Collaborating Centre for Infectious Diseases. Every Canadian case has been traced to a traveller who caught the virus abroad. The mosquitoes that carry it live in warmer places such as Florida, the Caribbean, and Central and South America, so the risk depends on where you travel.
How soon after a trip can symptoms start?
Symptoms usually begin within about two weeks of the bite that caused the infection, which is why a fever in the two weeks after you get home deserves attention. Tell your health care provider where you travelled, because the early illness can look like the flu and a blood test may be needed to confirm what it is.
Does travel insurance cover care for a mosquito-borne illness?
Most emergency travel medical policies cover sudden illness abroad, including infections spread by mosquitoes, as long as the policy is active and its conditions are met. Read the pre-existing condition and stability rules carefully before you leave, keep your policy number with you, and call the insurer's assistance line early if you need care.
Your next step
Heading somewhere warm this winter? A quick visit before you go can cover bite protection, travel medications, and what to watch for once you are home. The Medimap Health Hub has more on travel health, and you can find a walk-in clinic near you before the flight.
Disclaimer: This article is for general information only and is not medical advice. It does not replace a conversation with a doctor or other qualified health professional who knows your history. If you think you are having a medical emergency, call 911 or go to the nearest emergency department.
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