Florida sees first locally transmitted dengue case; what you need to know

As if COVID, monkeypox and tripledigit heat indices aren’t enough to make you consider sealing yourself inside an air-conditioned hazmat suit, the announcement by Florida’s health department that confirmed the first locally transmitted case of dengue in MiamiDade County might be enough to get you asking about measurements for such a suit.

You almost certainly have questions about mosquitoes and dengue fever and we have some answers.

The Miami Herald spoke with Dr. Mary Jo Trepka, professor and chair of the Department of Epidemiology at Florida International University’s Robert Stempel College of Public Health & Social Work, as well as representatives from the Florida Department of Health in Miami-Dade and the Miami-Dade Mosquito Control Division.

Here’s some of what you need to know:

What is dengue?

Dengue is a virus transmitted by the bite of infected female mosquitoes in the Aedes aegypti and Aedes albopictus species, according to the Centers for Disease Control and Prevention and World Health Organization. These mosquitoes can also carry the chikungunya, yellow fever and Zika viruses.

While these invasive mosquitoes have been discovered in California, including in San Joaquin County, no locally tested mosquitoes have been found to be infected with any of those diseases.

What are the symptoms?

The most common symptom of dengue is fever but people can also feel nauseous, vomit, develop a rash, have muscle, joint and bone aches and unusual bleeding and bruising. Typically, people recover after a week.

Other symptoms include headache, pain typically behind the eyes, muscle, joint, or bone pain, according to Florida’s health department.

Severe dengue can occur resulting in shock, internal bleeding and death. Most cases of severe dengue have occurred in Asian and Latin American countries, resulting in a leading cause of hospitalization and death among children and adults in these regions, according to the World Health Organization.

“If you or a family member develop the mentioned symptoms, visit your health care provider or local clinic,” the health department urges.

Most people infected with dengue have mild or no symptoms. Those that do develop symptoms typically recover after about one week, said the Florida Department of Health in Miami-Dade.

About 1 out of 20 people who initially get sick with dengue will develop severe dengue, Trepka said.

“People at risk of severe dengue include infants, pregnant women, people with chronic conditions such as diabetes, obesity and asthma and, very importantly, people who have had a previous dengue infection — that would be more likely in people who have lived in or traveled frequently to countries that are endemic for dengue including many Caribbean and Latin American countries,” she said.

Is dengue transmitted person to person, like COVID?

Dengue is not transmitted person to person the way COVID-19 or monkeypox gets passed.

“Rather, dengue is transmitted from person to mosquito to person to mosquito to person. Therefore, anyone who was traveling and got infected while traveling can return back to Florida infectious. This happens not only with dengue but also malaria. Then if Florida mosquitoes bite that returning, infectious traveler, they become infective. They then can bite other people, thereby spreading the virus,” Trepka said.

Have there been other outbreaks?

“This is the time of year when we see more mosquito-borne illnesses; in fact, we typically see more cases beginning in June and all the way up to December — think hurricane season!” Trepka said. “We typically also see West Nile virus cases this time of year. This is when we have had locally acquired dengue fever cases, and this is also the time of year when we had our Zika outbreak in Miami-Dade” (in 2016). There also was a dengue outbreak in Miami-Dade in 2019, and in Key Largo in 2020.

How to protect yourself

“All of these diseases can be prevented by good mosquito control. That includes not just the county Mosquito Control Department doing its work, but also people individually getting rid of standing water around their homes to collectively reduce the risk of mosquitoborne disease in the community,” Trepka said.

While no mosquitoes carrying dengue or yellow fever have been found locally, mosquitoes carrying West Nile virus are commonly found in San Joaquin County. Tips for local residents:

• Eliminate all sources of standing water on your property.

• According to label instructions, when outdoors, apply insect repellent containing EPA-registered active ingredients, including DEET, Picaridin, oil of lemon eucalyptus, or IR3535. Repellents keep mosquitoes from biting people.

• Avoid spending time outside when mosquitoes are most active, at dawn and dusk, and especially for the first two hours after sunset.

• When outdoors in cooler weather, wear long pants, loose-fitting longsleeved shirts, and other protective clothing.

• Exclude mosquitoes from your home with tight-fitting screens on doors and windows.

• Report daytime biting mosquitoes or significant mosquito infestations to San Joaquin County Mosquito & Vector Control District at www.sjmosquito.org, 209-982-4675 or 800-300-4675.