Local dengue cases are being raising questions about how the virus reached Tampa Bay and how it is spreading.
Three USF Health experts discuss what residents should know about , including its symptoms, how to protect against mosquitoes, what research is underway in Florida and what lessons can be learned from outbreaks in Latin America and the Caribbean.
, a researcher at the USF College of Public Health’s Center for Global Health and Infectious Disease Research, studies mosquito-borne diseases in Florida.
, dean of the USF Health College of Public Health and chief medical officer of the , whose international headquarters are based at USF, is an infectious disease epidemiologist.
, professor of Global, Environmental and Genomic Health Sciences, studies tropical and vector-borne diseases in Florida and Latin America.
What is dengue, and how do people get it?
Miley: Dengue is a viral illness that spreads through the bite of infected Aedes Aegypti or Aedes Albopictus mosquitoes. Both are already established here in Florida.
Local transmission occurs when someone gets dengue while traveling, then returns to Florida, and is bitten by a mosquito here that picks up the virus and later passes it on to another person.
Why are we seeing dengue in Tampa?
Miley: The mosquitoes that can spread dengue are already here. 911 are seeing warmer temperatures and lots of rain. This gives these mosquitoes plenty of places to breed. They don't need a puddle or a pond. All they need is water sitting in a flowerpot, bucket, tire, or other small container to breed.
Aedes mosquitoes also live very close to people in and around homes.
A C02 baited trap, used to attract mosquitoes bu mimicking human respiration (photos courtesy of Kristi Miley)
Dengue vector Aedes Aegypti, one of two species of mosquitoes carrying the disease
Mosquito caught in C02 baited trap near the bay area as part of Miley's research
What are the symptoms of dengue?
Vermund: Some people with dengue never feel sick but can still pass the virus to mosquitoes. But many people have a fever and headache. Pain behind the eyes is common, along with muscle and joint aches. Some people have nausea or develop a rash. While most people recover without serious problems, it can be life-threatening in a small number of people.
People should seek medical attention if they are experiencing . If dengue is circulating locally, your healthcare provider can send special blood tests for diagnosis.
Also watch the timing. Sometimes your fever goes away in a few days, but that's when a small proportion of people start to get much sicker. If other symptoms worsen as the fever comes down, seek medical care.
What should I do if I think I have dengue?
Vermund: Call your healthcare provider and make sure you're staying hydrated. Don't take aspirin or drugs like ibuprofen if you suspect dengue, as they can raise the risk of bleeding. Acetaminophen is recommended for fever and pain. Stay in touch with your provider, especially if you start feeling worse.
There's no antiviral treatment for dengue. While you're sick, try to avoid mosquito bites, too. People with dengue can pass the virus to mosquitoes during roughly the first week of illness. A mosquito can then pass the virus to a neighbor, co-worker or family member.
How can I prevent dengue around my home?
Miley: Emptying standing water around your home is extremely effective. Check places like flowerpots, children’s toys, buckets, gutters, and old tires. Mosquitoes don't need much water to lay their eggs.
If you find standing water, dump it. Don't think of mosquito protection as something you only need in the evening. Aedes aegypti also bites during the day, so when you're outside during daylight hours too. I also suggest checking the screens on your windows and doors for holes that could let mosquitoes inside.
What has your research found about dengue in Florida?
Miley: Once you've had one dengue serotype, you generally have long-lasting immunity to that particular one. There are four dengue serotypes, and we've seen evidence of all four in Florida. A second infection with a different serotype can sometimes lead to more severe disease, which is why we pay attention to which serotypes are circulating in Florida.
911've been looking back at what was happening when these cases showed up and asking questions like: Was it especially hot? How much rain had we had? What were mosquito numbers like? 911're trying to see whether those pieces tell us anything about when we're most likely to see dengue cases increase.
What lessons about combating dengue can we learn from the experiences of Latin America and the Caribbean?
鲹í-ҴDzԳá: The tropical regions of countries in Latin America and the Caribbean face dengue year after year, giving their scientists and public health teams extensive experience responding to it.
911 can learn from how other countries track cases, control mosquitoes, diagnose infections and respond when cases rise. Florida is closely connected to the region through travel, so sharing what we're seeing and learning from colleagues who've dealt with dengue for years benefits everyone.
Where does international collaboration fit in?
Miley: Last year, I presented our Florida dengue research at a for the Caribbean and Latin America in Jamaica. Dengue and other mosquito-borne diseases were a big part of the discussion.
During that meeting, I spoke directly with researchers who see much more dengue in their countries than we typically see in Florida. These relationships and connections help us reach out and exchange information quickly when cases rise.
鲹í-ҴDzԳá: Looking at what's happening across the region can also give us an idea of what we might see in Florida. Which serotypes are circulating? Are outbreaks changing? What are scientists seeing in mosquito populations? When we compare that with our own data, we can start to spot changes that might otherwise be missed.
What can Tampa Bay residents do right now?
Miley: Start with your own yard. After it rains, look for anything holding water and dump it. Clear gutters where standing water might harbor mosquito larvae. For containers too large to dump, “Mosquito Dunks” can kill mosquito larvae without harming animals or humans.
Use mosquito repellent during the day and evening. Remember that the mosquitoes that spread dengue bite during the day, too.