Should You Avoid Travel to Places With Dengue Outbreaks?

Luke Whelan Fact Checked
Woman and dog in bed with a mosquito net
© Holly Wilmeth / Getty Images

If you have a trip planned to a tropical country this summer, recent headlines might be giving you some anxiety.  

Dengue, a potentially fatal mosquito-borne viral infection, is exploding in the Caribbean and Central and South America. According to the Pan-American Health Organization, over 5 million cases of the disease have been reported in the region so far this year.  

Last year, climate change and an El Niño weather pattern combined to create the warmest year on record. One result was higher-than-normal numbers of dengue-carrying mosquitoes surviving the winter and spreading to new latitudes and higher elevations. This has caused unprecedented spikes in cases, especially in places not used to having such high levels of the virus. States of emergency have been declared in Puerto Rico, Peru and parts of Brazil.  

“The incidence of dengue is quite high right now, and a lot of that is because it’s going into new populations where people didn’t have any previous immunity,” says Dr. Indi Trehan, an associate professor in emergency medicine and infectious diseases at UW School of Medicine’s Department of Pediatrics, whose research and clinical work has focused on the diagnosis and management of tropical diseases. “As a traveler, there are more places you have to worry about now than you would’ve had to five, 10 years ago.” 

So does that mean you should cancel your visit to San Juan or ditch your beach vacation in São Paulo? Here is what you need to know.   

How do I know if I should call off my trip?

If a country is in the middle of an outbreak of dengue or any other infectious disease, it’s important to do some research about what is going on there. Check the U.S. Department of State for travel advisories and the Centers for Disease Control and Prevention’s website to read about the risks of traveling to the country you plan to visit. If the area has limited healthcare resources, it might not be wise to go if you won’t have access to medical attention in the event you do get sick. That’s not to mention possibly burdening an already overtaxed healthcare system.

In the end, you need to make your own personal risk assessment. If you are immunocompromised or have a chronic disease, your risk tolerance will likely be very different, especially if you won’t have access to the medical care you’d need if a complication with your condition arises. And if you’re pregnant, it might be worth it to avoid places with mosquitoes carrying tropical diseases altogether — if dengue is endemic, it’s possible Zika and malaria are too, which can cause serious complications for pregnancy. 

Is there a vaccine for dengue? 

Unfortunately, there isn’t a vaccine or preventive medication for dengue that’s currently available for travelers. Dengue vaccines exist but only for people who live in an endemic area. That’s because, typically, the first time you get dengue, it’s very mild — many people don’t experience any symptoms at all.  

But if you get it again, the risk increases. 

“The second time you get it, especially if it’s a different strain, then you can have very severe illness,” says Trehan.  

Think unbearable joint pain (the disease is also called “breakbone fever”), high fever, vomiting and, in its worst form, hemorrhagic fever that can lead to organ failure.  

So the bad news is that you currently can’t take a vaccine, but if you’ve never had dengue before, it’s much less likely to be severe.  

“Dengue is the most common of the major tropical illnesses that people get when they travel to South America,” says Trehan. “So it’s pretty wise for American travelers to be aware of the dangers and lower their risk.”

How else can I protect myself?

If you decide to go, there are specific precautions to take in a tropical region to avoid mosquito-borne diseases. (The same species of mosquito that carries dengue also transmits Zika, yellow fever and Japanese encephalitis.) 

Don’t forget protection 

The best thing you can do? Be diligent about your personal protective equipment. This includes bed nets, keeping your arms and legs covered day and night, and wearing insect repellent with at least 30% DEET on exposed skin.  

“If you’re also wearing sunscreen, apply it first and make sure it has dried completely before applying repellant,” says Dr. Nandita Mani, an infectious disease specialist and associate medical director of infection prevention and control at UW Medical Center. “And be aware that mosquitoes carrying dengue bite throughout the day but have peak activity in the early morning, late afternoon, and evening.” 

You’re not safe at night either, though: The mosquitoes that carry malaria are nocturnal. 

Visit a travel clinic to see what other vaccines you can get 

While a dengue vaccine doesn’t exist for travelers, many others do that you should consider, depending on where you’re going, what kind of trip it is (a tour of major cities versus a jungle trek), and how long you’ll be there. 

Vaccines are available in the U.S. for typhoid, yellow fever, Japanese encephalitis, rabies and cholera, as well as prophylaxis pills to prevent malaria. Many of these diseases, like dengue, are spreading to new places at faster rates thanks to climate change. Remember also that no vaccine or preventive medication will be perfect at protecting you, and most have specific requirements for how they need to be administered to make them as effective as possible. 

The best place to go to find out which vaccines are prudent to get is a travel clinic like the Travel Medicine Clinic at UW Medical Center – Northwest or the Infectious Disease & Travel Medicine Clinic at Harborview.

Finally, don’t forget about staying up to date on your basic shots for flu, COVID-19, tetanus, hepatitis and other routine vaccines. 

“Respiratory infections, especially in the tropical regions, are more of a year-round thing rather than just a winter problem,” says Trehan. “For example, we see COVID spikes every summer.”’ 

Measles, too, is increasing globally, including in many places in Europe.  

“This is a highly contagious infectious disease, and it’s important to make sure that you’re up-to-date with vaccination,” says Mani. If you’re traveling with a baby who hasn’t gotten their measles vaccine yet, Mani recommends getting an early dose — they can get one as young as six months old.  

Tell your doctor where you’ve been  

If you do start feeling sick after visiting a country with dengue or any other infectious disease, head straight to the emergency room. They’re more likely to have the resources needed to test you quickly for travel-related diseases.  

“If you’re concerned at all, see a doctor,” says Mani. “You should seek medical attention if you return with unexplained fever, vomiting, new rash, diarrhea, severe headache, joint pains, jaundice or pain behind the eyes.” 

And when you get there, tell them where you’ve been traveling.  

“When you come back and you feel sick, the first thing you should say is, ‘I was in the middle of a safari in Kenya,’” says Trehan. “Don’t make it a mystery, let your healthcare providers know where you’ve been and what you did and what kind of exposures you may have had, including food, water and bug bites.” 

That information will, of course, make it much easier for them to diagnose an infectious disease like dengue and start treating you faster.  

Don’t forget about other risks 

Despite how scary a disease like dengue can be, Trehan points out that the things most likely to pose a risk to your health while traveling are much more commonplace.  

“The No. 1 risk is road traffic accidents,” says Trehan. “So be really cautious about what kind of vehicle you’re getting into. The second biggest risk is colds, flu, diarrhea, the sort of stuff you could get at home.” 

Then there are the health problems you already have.  

“Maybe you’re forgetting to take your meds on time, or you’re sleep deprived, or you’re drinking a little more, or you’re not eating as well and out of your normal exercise and sleep routines, so your own health problems can get worse,” he says.  

But in most cases, Trehan doesn’t think you should stay home. 

“Life’s short. I think you got to go travel,” he says. “Enjoy the world, enjoy the experience of seeing things and seeing people in new places, but just be prepared.”