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 impressive 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 2016). 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, now that the first few dozen cases were recently recorded here. 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 other 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 until more is known. Aside from being spread by mosquitoes, Zika also has recently been transmitted from person to person through sexual contact in the United States. The Zika virus is a developing story that everyone is watching closely.    

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 five deaths in Costa Rica from severe Dengue, four of which were in 2010 and one in 2013. Cases of regular Dengue Fever vary each year, but average around 15,000/year. In 2013 (the year we moved to Costa Rica), cases spiked at 49,993. The last two years, numbers have been closer to the average, with about 11,000 cases in 2014 and 17,000 in 2015. 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 but is also relatively new, occurring in only the last couple of years. In 2015, there were less than 5,000 cases reported. 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 simply 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 bug spray.

DEET Options

The CDC recommends an insect repellent that contains at least 20% DEET. You can buy insect 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 very 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.


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 actually work quite well in Costa Rica. We regularly use Repel’s Lemon Eucalyptus spray and have found it to work just as well as our sprays containing DEET. Essential oil blends work well too. You can mix your own using lemongrass, citronella, clove, eucalyptus, etc. or you can buy something already made. One popular essential oil-based repellent is doTerra TerraShield Essential Oil Repellent Blend. They also have a new product (2016) called the Outdoor Blend, which we just got our hands on. It’s more expensive, but we’ve found it to be the most effective against bites, not oily, and pleasant smelling too. Another option that we haven’t tried ourselves but have heard good things about is Burt’s Bees All-Natural Herbal Insect Repellent. Unfortunately natural repellents are hard to find in most areas of Costa Rica so we recommend bringing these from home too.

Cover Up

In addition to using repellent, it is also a good idea to protect your skin by covering up. Here are some tips:

  • When possible, cover all exposed skin by wearing light-colored, long-sleeved shirts, long pants, and hats. 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.

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 current bulletins with the latest data on all three diseases.
  • 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.

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Have any tips to prevent mosquito bites? Leave a comment below (email subscribers click here to post your comment online).


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