Dengue in the Florida Exam Room: A Physician’s Guide

A 46-year-old man walks into a South Tampa urgent care in the second week of August with three days of fever, a headache that sits behind his eyes, and back pain that kept him awake. His flu and COVID tests are negative, and he has not left Hillsborough County since Christmas. In most years the visit would end with a viral syndrome and a bottle of ibuprofen. In 2026 that patient had a reasonable chance of having dengue, and the ibuprofen was the wrong drug.

Locally acquired dengue is no longer an exotic footnote in Florida. The state counted 91 local cases in 2024 and passed that number before Labor Day this year. The clinical questions do not expire when the alert lifts, because the next cluster will start the way this one did, in an exam room where nobody was thinking about it.

Why Dengue Is Now a Florida Problem

The Florida Department of Health’s arbovirus surveillance report for the week ending September 5, 2026 counted 111 locally acquired dengue cases in six counties, 95 of them in Hillsborough, with the rest in Miami-Dade, Pinellas, Pasco, Orange, and Palm Beach. The same report counted 160 travel-associated cases for the year, 123 of them in people returning from Cuba. Health News Florida reported on September 10 that the state was investigating whether an 80-year-old South Tampa woman who died the previous week had contracted dengue locally.

These numbers follow a pattern. CDC’s March 2025 health advisory recorded 91 locally acquired Florida cases in 2024 alongside 1,016 travel-associated cases and warned that transmission across the Americas remained high. Aedes aegypti breeds in the bottle caps and bromeliads of neighborhoods across peninsular Florida, and every viremic traveler who comes home is a potential index case. The public health response follows the physician’s diagnosis and cannot precede it.

Recognizing the Three Phases, and the Trap at Defervescence

CDC describes dengue as a three-phase illness. The febrile phase runs two to seven days, with high fever that can be biphasic, severe headache, retro-orbital pain, myalgia and arthralgia, and often a rash. The critical phase begins when the fever resolves and typically lasts 24 to 48 hours. Most patients improve during that window; a minority develop plasma leakage, and in that group shock can arrive suddenly in a patient who looked well an hour earlier.

The trap is the timing. The patient feels better as the fever breaks, and nobody sees her on day five unless somebody told her to come back. CDC states that warning signs of progression to severe dengue usually appear in the late febrile phase around the time of defervescence. Those warning signs are abdominal pain or tenderness, persistent vomiting, clinical fluid accumulation, mucosal bleeding, lethargy or restlessness, liver enlargement, and a rising hematocrit with a falling platelet count.

Testing by Day of Illness, Not by Reflex

The right test depends on the calendar. CDC’s guidance for the first seven days of illness is to order either a nucleic acid amplification test or an NS1 antigen test, together with an IgM antibody test. NS1 antigen can be as sensitive as molecular testing in that window, and IgM becomes useful after about day three and remains detectable for roughly three months.

A positive NAAT or NS1 result is confirmatory. IgM is presumptive, and CDC is explicit that cross-reactivity with other flaviviruses, Zika above all, limits dengue serology. The 2025 advisory adds that when the dengue tests are negative and the picture still fits an arboviral illness, the patient should be evaluated for Zika, chikungunya, and Oropouche.

Management in the Office and in the Hospital

CDC’s management guidance is short. Control fever with acetaminophen and avoid aspirin and NSAIDs, because the bleeding risk is real in a disease whose severe form is defined in part by hemorrhage. Oral hydration is usually sufficient in the outpatient. Admit patients with any warning sign, with co-existing conditions that raise the risk of severe disease, including pregnancy, who are under one year old or over 65, or who live alone or far from care. For inpatients, follow the hematocrit every four to six hours and titrate fluids to its trend rather than to a protocol.

Every outpatient with suspected dengue should leave with a written instruction to return immediately if warning signs appear, an explanation that the critical phase typically occurs three to eight days after the fever started, and a reminder to use an EPA-registered repellent for three weeks so as not to seed the next case on the block.

Reporting: Florida Wants the Call on Suspicion

This is the part of dengue care that is specific to Florida law, and the part most often missed. Section 381.0031(2), Florida Statutes, requires any licensed practitioner who diagnoses or suspects a disease of public health significance to report it immediately to the Department of Health. Rule 64D-3.029 of the Florida Administrative Code places dengue, and arboviral infections generally, in the category the rule calls “suspect immediately,” which the state’s practitioner reporting list translates as report immediately, 24 hours a day and seven days a week, by phone, upon initial suspicion or laboratory test order.

The trigger is the order, not the result. A physician who sends an NS1 and waits three days for the result before calling has missed the window the rule was written to protect, because mosquito control needs to know where a viremic patient sleeps while the patient is still viremic. Every county health department maintains an epidemiology line, and it belongs on the wall where the blood is drawn.

What Florida Physicians Should Do Now

1. Add dengue to the fever template. Any febrile patient seen during mosquito season gets a travel history, a mosquito exposure question, and a day-of-illness note. The 14-day exposure window in the CDC advisory applies to a trip to Havana and to a backyard in Seminole Heights alike.
2. Order the paired test and label the day. NS1 or RT-PCR plus IgM in the first week, with the day of illness on the requisition. Confirm before the season which dengue assays your reference laboratory runs and how fast.
3. Write acetaminophen and say the word NSAID out loud. Patients reach for ibuprofen on their own, so the instruction to avoid it belongs in the after-visit summary.
4. Schedule the defervescence check. A call or visit on the day the fever is expected to break, with explicit return precautions, is the single intervention most likely to catch severe dengue before it becomes shock.
5. Call the county health department when you order the test. Not when the result returns. None of this constitutes legal advice, so a practice that wants to know how the reporting rule and its penalties apply to its own workflow should ask a Florida health law attorney. Then take the question to the county medical society, because a shared reporting protocol across a county’s urgent cares could shorten the next outbreak.

The Bigger Picture

Dengue has been a disease of other places for most of our careers, and the habits that follow from that assumption are the reason local outbreaks grow before anyone notices them. The physician who sees the first febrile patient without a travel history is the surveillance system, whether or not the state has issued an alert that week, and treating that responsibility as ordinary clinical care rather than as an outbreak measure is what it means for Florida physicians to lead on this.

Frequently Asked Questions

Is dengue a reportable disease in Florida, and when must a physician report it?

Yes. Rule 64D-3.029, Florida Administrative Code, lists dengue as a condition to be reported on suspicion, and the Department of Health’s practitioner list marks it for immediate reporting by phone, 24/7, upon initial suspicion or laboratory test order. Reports go to the county health department where the patient was seen.

What is the best test for dengue in the first week of symptoms?

CDC recommends a nucleic acid amplification test or an NS1 antigen test, paired with an IgM antibody test, during the first seven days of illness. A positive NAAT or NS1 result confirms the diagnosis, while a positive IgM alone is presumptive because of cross-reactivity with other flaviviruses such as Zika.

Can a Florida patient get dengue without traveling?

Yes. The Florida Department of Health counted 111 locally acquired cases in six counties by early September 2026, most of them in Hillsborough, and 91 locally acquired cases statewide in 2024. Aedes aegypti, the mosquito that transmits dengue, is established across most of peninsular Florida.

Why should NSAIDs be avoided in a patient with suspected dengue?

CDC’s management guidance is to control fever with acetaminophen and avoid aspirin and NSAIDs such as ibuprofen because of the bleeding risk in a disease that can cause thrombocytopenia and hemorrhage. The instruction applies from the moment dengue enters the differential, before test results return.

When is a dengue patient most at risk of severe disease?

The critical phase begins when the fever resolves, typically three to eight days after onset, and lasts 24 to 48 hours. Warning signs such as abdominal pain, persistent vomiting, mucosal bleeding, lethargy, or a rising hematocrit with falling platelets during that window call for admission and close monitoring.

This article is general information for physicians and is not legal or clinical advice for any individual patient. Consult current CDC and Florida Department of Health guidance and your county health department.

This article was drafted with the assistance of AI writing tools, then reviewed, edited, and approved by Dr. Sean C. Orr, M.D., who holds full editorial responsibility for its content. The header illustration was created with AI image tools.

References

1. Florida Department of Health, “Florida Arbovirus Surveillance, Week 35: August 30 to September 5, 2026.” floridahealth.gov
2. Florida Department of Health, “Reportable Diseases/Conditions in Florida: Practitioner List.” floridahealth.gov
3. Florida Administrative Code, Rule 64D-3.029, “Diseases or Conditions to be Reported.” law.cornell.edu
4. Centers for Disease Control and Prevention, “Clinical Features of Dengue.” cdc.gov
5. Centers for Disease Control and Prevention, “Clinical Testing Guidance for Dengue.” cdc.gov
6. Centers for Disease Control and Prevention, “Clinical Care of Dengue.” cdc.gov
7. Centers for Disease Control and Prevention, Health Alert Network CDCHAN-00523, “Ongoing Risk of Dengue Virus Infections and Updated Testing Recommendations in the United States” (March 18, 2025). stacks.cdc.gov
8. Health News Florida / WUSF, Rick Mayer and Kerry Sheridan, “Florida investigates possible Hillsborough death related to dengue as cases hit 95” (September 10, 2026). wusf.org