Dengue is one of the most spread diseases on the planet; estimations indicate around 50-100 million cases of dengue each year across the world. The disease has long been an issue in Brazil, and the number of infected patients is currently increasing. Last year there were 1.6 million recorded cases, roughly triple the amount of 2014. While headlines are focusing on Zika, Dengue is actually a much more serious virus; 863 dengue-related deaths were recorded last year in Brazil. Zika in contrast rarely causes death.

What is Dengue?

Dengue illness is caused by a virus spread through mosquito bites. Dengue is transmitted by several species of mosquito within the genus Aedes, principally A. aegypti. The virus has five different types; infection from one type usually gives lifelong immunity to that type, but only short-term immunity to the others. Subsequent infection from a different type increases the risk of severe complications.

The symptoms are similar to both Zika and Chikungunya, which are also transmitted through Aedes mosquitoes. Misdiagnosis therefore sometimes occurs.


Symptoms include fever, headache, nausea, vomiting, rash, and pain in the eyes, joints, and muscles.

Symptoms can take up to 2 weeks to develop after you are bitten by an infected mosquito, but they usually end in a week. In severe cases, symptoms may include intense stomach pain, repeated vomiting, difficulty breathing, becoming drowsy or irritable, and bleeding from the nose or gums.

See a doctor right away if you have these symptoms. Severe cases of dengue can lead to death, especially among young children.

What is my risk?

Travelers who go to tropical and subtropical regions are at risk of getting dengue. These areas include parts of the Caribbean, Central and South America, Western Pacific Islands, Australia, Southeast Asia, and Africa.

In Brazil, the risk of contracting the disease is highest between January-May due to favorable climate conditions for the mosquitos. During other months, the risk is somewhat lower but still a factor.

As mentioned, Brazil has seen a significant increase of Dengue during 2015-2016, and it is expected to continue being a significant health threat in all of Brazil.


The mosquito that carries the dengue virus can bite during the day and night, both indoors and outdoors, and often lives around buildings in urban areas. Aedes mosquitoes are present in virtually all of Brazil, however usually not above altitudes of 4,500 feet (1,500 meters).

How can you avoid Dengue fever?

Prevention depends on the control of- and protection from the bites of the mosquito that transmits it. People can prevent mosquito bites by wearing clothing that fully covers the skin, using mosquito netting while resting, and/or the application of insect repellent (DEET being the most effective).

Estimations indicate there there are around 50-100 million cases of dengue each year across the world. In Brazil the disease have long been an issue, and the number of infected patients are currently increasing.

Treatment of acute dengue is supportive, using either oral or intravenous rehydration for mild or moderate disease, and intravenous fluids and blood transfusion for more severe cases.

There are no approved vaccines for the dengue virus.

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