Costa Rica and Mosquitoes: Tips to Prevent Zika, Dengue, and More

Last Updated: May 21, 2019

Although Costa Rica has some amazing wildlife, not all creatures in its rainforests are postcard worthy. In fact, some, like the mosquito, are dreaded because of their ability to pass on diseases like Zika, Dengue, and Chikungunya to humans. While these illnesses are a real concern in Costa Rica, a little bit of knowledge goes a long way in prevention. In this post, we’ll discuss Costa Rica’s most common mosquito-borne illnesses and give you some tips on how to stay safe during your visit.  

Costa Rica and Mosquitoes: Tips to prevent Zika, Dengue, and more | Two Weeks in Costa Rica

Mosquito-Borne Illnesses in Costa Rica

As a traveler, you should know that Costa Rica’s government takes mosquito-borne illnesses very seriously and has aggressive campaigns to prevent the spread of such diseases. These include public outreach to eliminate breeding sites as well as targeted chemical spraying in areas where diseases have been recorded. Our friend actually worked for Costa Rica’s Ministry of Health for a while, eradicating mosquitoes, and told us that each day they were given the addresses of people who had been diagnosed with a mosquito-borne illness. They would then go door to door in those neighborhoods, handing out educational pamphlets, emptying standing water containers, and spraying to kill mosquito larvae.

These measures have helped to control the spread of mosquito-borne diseases in Costa Rica, but conditions are constantly changing. At times, there are reports of small outbreaks in certain areas, and at other times, things are very quiet. We don’t want to scare you off from your vacation, but we also want you to know what’s out there. Our goal is to give you as much information as possible so that you can stay safe.

Here are the most common mosquito-borne threats that you need to be aware of in Costa Rica (Updated May 2019). Later in this post, we’ll cover our tips on how to prevent mosquito bites in the first place.

Zika Virus

The Zika virus is the latest scare in Costa Rica and throughout Latin America. The symptoms of the Zika virus can include a mild fever, skin rash, and conjunctivitis. These symptoms normally last for two days to a week, but many people who have the disease show no signs at all. While Zika has relatively mild symptoms, the biggest danger according to the CDC (U.S. Center for Disease Control) is to women who are pregnant or planning to become pregnant. Reports from countries such as Brazil show an alarming rate of the birth defect microcephaly in children born to mothers who are infected with Zika. For this reason, the CDC recommends that those women consult their doctor or postpone their travel plans to countries that have the disease. Aside from being spread by mosquitoes, Zika also has been transmitted from person to person through sexual contact in the United States.

In 2017, Costa Rica had about 2,400 suspected cases of Zika, of which 359 were confirmed. We couldn’t locate the final data on the number of confirmed cases in 2018, but there were a total of 431 suspected cases so the number confirmed was likely ultimately less than that. 

Dengue Fever

Dengue Fever has been present in Costa Rica much longer than Zika. Its symptoms can vary from mild fever to incapacitating high fever, with severe headache, pain behind the eyes, joint and muscle pain, and rash. Although much less common, severe dengue (also known as dengue hemorrhagic fever) has symptoms of fever, persistent vomiting, abdominal pain, bleeding, difficulty breathing, and in rare cases, death.

Since 2010, there have been seven deaths in Costa Rica from severe Dengue. Cases of regular Dengue Fever vary each year and had been reaching around 15,000/year in recent years. There were about 11,000 cases in 2014, 17,000 in 2015, 23,000 in 2016, and 5,500 in 2017. In 2018, the number of cases was down to around 2,700. Like we said above, the Costa Rican government’s aggressive campaigns to eradicate mosquitoes help to keep these numbers in check.


Chikungunya is much less of a threat in Costa Rica and is also relatively new, occurring in only the last couple of years. In 2017, there were 396 cases, and in 2018, 146 cases. Symptoms of Chikungunya are an abrupt fever, which is usually accompanied by joint pain. Other signs include muscle pain, nausea, headache, fatigue, and rash. The joint pain associated with Chikungunya often can be very debilitating, but usually only lasts for a few days or weeks. Most patients recover fully, but in some cases joint pain can persist for months or even years.

How to Prevent Mosquito Bites

The three viruses we mentioned above, Zika, Dengue, and Chikungunya, are all transmitted by the bite of an Aedes mosquito. These types of mosquitoes are most active during the daytime and usually have white markings on their wings or body. In order to get you sick, the mosquito that bit you has to have previously bitten someone infected with one of the viruses.

Here are our tips on how to avoid bites from the start.

Costa Rica and Mosquitoes: Tips to prevent Zika, Dengue, and more | Two Weeks in Costa Rica
Aedes mosquito. Photo credit – CDC and James Gathany

Watch Out for These Spots

Mosquitoes in Costa Rica usually won’t bother you if you’re sunbathing on the hot sand or walking in the heat of the day. But watch out if you are resting under palm trees, hiking on shady trails, or passing by wetlands, ponds, or rivers. Also be extra careful in the morning and evening hours when it is a little cooler outside. We’ve been hit hard when eating at restaurants with outdoor seating. They love to hide out under the tables and bite your legs and ankles.    

Mosquitoes are also much more prevalent during the rainy season months of May through November. With more water, they are able to reproduce faster so have higher numbers. Avoiding the rainiest areas of the country can help you avoid bites. Read our Weather post for more information about which areas of Costa Rica receive the most rain.

Insect Repellent 

An obvious way to prevent bites is to use insect repellent.

DEET and Picardin Options

The CDC recommends an insect repellent that contains at least 20% DEET. You can buy repellent at most grocery and convenience stores in Costa Rica, but unfortunately they mostly carry ones that have 15% DEET. This may work for a short amount of time but a higher concentration will last longer. Insect repellent is also expensive here, at about $10 a can. For these reasons, we recommend bringing your own supply. For serious hiking through the rainforest, we have used Repel 100, which is 98% DEET, but try to apply only when we know we will be washing it off within a few hours since it is so strong. Ben’s 30% Wipes are milder and good to keep in a backpack or purse. Here are some other options that are good for travel.

An alternative to DEET that is starting to become popular is Picardin. Picardin-based repellents have been proven to be just as effective as DEET in preventing bites and also keep mosquitoes farther away. Instead of landing on you and not biting, like with DEET, Picardin is said to prevent the insect from landing in the first place. We have used Sawyer’s 20% Picardin lotion with success. We like the lotion because we can tell that it has been applied to cover all areas. It also doesn’t smell bad and dries after application.

Costa Rica and Mosquitoes: Tips to prevent Zika, Dengue, and more | Two Weeks in Costa Rica
Insect repellent for sale at a grocery store in Costa Rica

Natural Options

While DEET is proven to be effective against mosquitoes, a lot of people (us included) try to avoid it because of its potential harm to human health. Fortunately, there are some more natural options that work quite well in Costa Rica. We regularly use a few different products. Repel’s Lemon Eucalyptus spray works just as well as our repellents containing DEET.

Essential oil blends are fairly effective too. You can mix your own or buy something already made. Our standby is a combination of coconut oil and lemon eucalyptus oil. Lemon eucalyptus is supposed to be one of the best essential oils for fighting mosquitoes according to scientific studies.

A premixed essential oil-based repellent that we like is doTerra TerraShield Outdoor Blend. It’s more expensive, but we’ve found it to be the most effective against bites, not oily, and pleasant smelling too. Unfortunately, natural repellents are hard to find in most areas of Costa Rica so we recommend bringing these from home too.

Cover Up

Covering up is a great way to prevent mosquito bites and lessens the need to use repellents. Some important tips are below. For a full write-up of what clothing to wear to prevent insect bites, read our new post Mosquito Repellent Clothing for Costa Rica. 

  • When possible, cover all exposed skin by wearing light-colored, long-sleeved shirts and long pants made of synthetic material that bugs cannot easily bite through. Loose-fitting, breathable pants like these are a good option for Costa Rica since it is so hot.
  • Sleep in air-conditioned or screened rooms. Keep in mind when looking at eco-lodges and hotels in Costa Rica that some accommodations are open air. This means that there is only a mosquito net covering the bed, and mosquitoes and other insects can slip through screenless windows or slats in the walls. It is best to avoid this style of lodging if you’re prone to bug bites.
  • If you are staying in open air accommodations like we describe above, at a minimum, make sure you have a bug net for sleeping.

Don’t be a Target

Many people don’t realize it, but mosquitoes can smell you from up to 50 yards away. To prevent them from honing in on your exact location, there are a few tactics you can use.

  • If you are staying in one place for a while, like a vacation rental or cabin, be careful not to leave sweaty clothing and footwear hanging out to dry near where you sit. A 1999 study in the Journal of Chemical Ecology found that after a couple of days, the bacteria growing on sweaty clothes attracted many more mosquitoes than “fresher” sweaty clothes.
  • You also can try to mask the chemical compounds that mosquitoes are attracted to by burning incense, citronella, or mosquito coils. Mosquito coils are available in grocery and convenience stores all around Costa Rica and cost only about $1 a package. When we sit outside, especially in the rainy season, we usually burn a couple of these coils on each end of our porch, setting up a sort of smoke screen. It doesn’t work perfectly but it definitely helps.
Costa Rica and Mosquitoes: Tips to prevent Zika, Dengue, and more | Two Weeks in Costa Rica
Mosquito coils can be found in grocery stores throughout Costa Rica

Mosquitoes in Costa Rica are not fun to talk about, but we know that they are on everyone’s mind now that the Zika virus is making headlines worldwide. Remember, though, that not every mosquito is infected, and your chances of contracting something during a short visit are relatively low. The preventative measures we’ve discussed in this post will go a long way towards prevention and hopefully will ease your worries so that you can enjoy all of the other, more beautiful creatures that this country has to offer. 

These are our tips for protecting yourself against mosquito bites in Costa Rica based on our experience living in the country. We are not experts in disease prevention or doctors and are not intending to give medical or other professional advice. If you’re unsure if you should travel to Costa Rica, consult the CDC (Center for Disease Control) and WHO (World Health Organization) websites for more information or seek the advice of a medical professional.

Last Updated: May 21, 2019

Additional Resources

  • Costa Rica’s Ministry of Health: In Spanish, but they have an option to translate the site. Covers all the major health issues facing Costa Rica. The Información sobre Zika page has bulletins with recent data on all three diseases. In late 2018, the government stopped doing these bulletins, but more current information (2019) still can be found on their website here.
  • CDC: Info on travel advisories and ways to prevent mosquito bites.
  • WHO: Detailed info on different outbreaks throughout the world, including the Zika virus.
  • The Tico Times: Costa Rica’s leading English-language newspaper. Has several stories on Dengue and Zika in Costa Rica and are another good source for current information

Some of the links in this post are connected to affiliate programs we have joined. As an Amazon Associate we earn from qualifying purchases.

Have any tips to prevent mosquito bites? Leave a comment below.

Looking for more information to help you plan? Check out these posts: