Dengue in Puerto Rico: symptoms, testing and warning signs

Dengue is a viral infection spread by the Aedes aegypti mosquito. There are four dengue viruses, so you can get it more than once. The same mosquito spreads chikungunya and Zika in Puerto Rico, and the symptoms overlap; only a lab test tells them apart. Zika is a particular concern in pregnancy.

Most people feel better in about a week, but about 1 in 20 people who get sick develop severe dengue, which is a medical emergency.

If you have a fever and no warning signs, you see Dr. Diana Nieves Castro by video. She is a general practice physician licensed in Puerto Rico with several years of emergency-department experience, so she knows what can be managed at home and when you need to be seen in person. We evaluate, diagnose and treat; if needed, we give you a lab order for a lab near you.

The doctor goes over how many days you have had a fever, how well you are keeping fluids down and what to watch for. If appropriate, the doctor prescribes and we send your prescription to your pharmacy. This is virtual urgent care for problems that are not emergencies, in English or Spanish.

We see adults and children of all ages. For patients under 21, a parent or legal guardian stays on camera for the whole visit and shows photo ID. You need to be physically in Puerto Rico during the visit, and visitors are welcome. If you are here on vacation, see also sick on vacation in Puerto Rico.

Video doctor visits 24/7 — book online and choose your time right away.

A doctor visit has the same price for every age, with no membership. Your card is charged when you request the visit, and you get a full refund if the clinic can’t see you. A doctor's note after your visit is included at no extra charge. The service is run by The Health Initiative, a nonprofit. See pricing or book your visit.

According to the CDC, dengue shows up as [fever](route:symptom-fever) plus one or more of:

Don't take aspirin or ibuprofen. For fever and pain, the CDC recommends acetaminophen. Rest as much as you can and drink plenty of fluids, water or drinks with added electrolytes, to avoid dehydration.

During the first week the virus is in your blood, so prevent mosquito bites to avoid spreading it to the people you live with.

If the doctor thinks a test will help, she gives you a lab order for a lab near you. The CDC recommends a molecular test (such as RT-PCR) or an NS1 antigen test in the first 7 days of symptoms, and IgM antibody testing from day 3. Commercial labs offer dengue testing, and the doctor goes over the result with you.

Warning signs usually begin 24 to 48 hours after the fever has gone away, just when many people think they are recovering. If you have or recently had dengue and notice any of these, go to an emergency room or call 911:

• Belly pain or tenderness
• Vomiting at least 3 times in 24 hours
• Bleeding from the nose or gums
• Vomiting blood, or blood in the stool
• Feeling extremely tired, restless or irritable

The CDC warns that dengue can become severe within a few hours. Don't wait to see if it passes, and don't book a video visit for these signs: go straight to the emergency room.

The Pan American Health Organization (PAHO) sorts dengue into three groups: dengue without warning signs (fever with general symptoms; if that is you, the doctor can see you by video), dengue with warning signs (for example, intense, continuous belly pain or persistent vomiting) and severe dengue (shock, severe bleeding or severe organ damage). Dengue with warning signs and severe dengue are treated in the emergency room.

Children can get severe dengue too, and the same signs apply. If your child is very drowsy or hard to wake, call 911. See also fever in children.

Oropouche is another fever-causing virus that can be mistaken for dengue and chikungunya. According to the CDC, Oropouche virus spreads to people mainly through the bite of infected biting midges, tiny flies; some mosquitoes can also spread it. Symptoms start suddenly: fever, severe headache, chills, muscle aches and joint pain. They usually last 2 to 7 days and can come back days or weeks later.

Pregnancy needs extra care. Brazil has reported cases, still under investigation, in which the virus passed from a pregnant woman to her fetus, with fetal death or birth defects such as microcephaly. If you are pregnant and have a fever, tell the doctor about any midge or mosquito bites or recent travel.

No medicine treats Oropouche. The CDC recommends rest, fluids and acetaminophen for fever and pain, and avoiding aspirin and other anti-inflammatory medicines such as ibuprofen, just as with dengue. Because the symptoms overlap, only a test tells them apart: if the doctor thinks you need one, she gives you an online lab order. To prevent it, use insect repellent and avoid midge and mosquito bites.

Puerto Rico's Department of Health declared a dengue public health emergency in March 2024. According to the CDC, 6,291 cases were reported in 2024: 52.3% of patients were hospitalized, 264 had severe dengue and 11 died. As of March 7, 2025, 936 cases had been reported, a 113% increase over the same period in 2024.

The CDC lists dengue as a risk for travelers to Puerto Rico. Use an EPA-registered repellent (for Puerto Rico the CDC recommends products with at least 20% DEET), wear long sleeves and pants, and sleep in rooms with window screens or air conditioning. After a hurricane, the CDC repeats this advice: see health after a hurricane. If you get a fever after your trip, tell your doctor you were in Puerto Rico. Not sure whether you need the ER, urgent care or a video visit? Read ER vs urgent care in San Juan.