Over 600,000 people are expected to be traveling from around the world to attend the 2014 FIFA World Cup, which began on June 12 in Brazil and will continue until July 13. As you may know from other Disease Daily articles on mass gatherings such as Occupy camps and the Hajj, these types of events present a high risk for infectious disease spread. Aside from the diseases that international travelers would usually expect to watch out for in Brazil—such as traveler’s diarrhea and dengue—they must also be prepared to encounter diseases brought by travelers from other countries, such as measles from the United States or chikungunya from the Caribbean. World Cup fans from one country could bring a virus to Brazil, spread it to fellow fans from all over the world, and when everyone returns to their home countries, the disease would travel with them. Because no one wants an unexpected illness to ruin their World Cup experience, here is a run-down of some of the infectious diseases fans should be aware of, and what they can do to avoid getting sick. For a visual representation of the global health implications, HealthMap has partnered with Brazil's Ministry of Public Health to create a map for the World Cup that displays the diseases of particular interest for this mass gathering.
A study by Harvard University researchers evaluated the illnesses posing the greatest risk to World Cup attendees. The leading cause of illness in travelers returning from Brazil between 1997 and 2013 was skin worms, particularly cutaneous larva migrans. The hookworm causing this disease is often found in canine and feline feces; when found on the beach, the worms can penetrate bare skin of beachgoers when they step in the sand. Rather than avoiding the beach altogether, travelers are advised to wear proper footwear and avoid sitting on bare sand.
The next leading cause of illness was traveler’s diarrhea, which affects 20-50% of international travelers each year. To avoid traveler’s diarrhea, the CDC recommends avoiding food and beverages from street vendors and unhygienic establishments, avoiding raw or undercooked meat and seafood, and avoiding raw fruits and vegetables (unless peeled by the traveler). Tap water, ice, unpasteurized milk, and dairy products may also put consumers at risk of contracting traveler’s diarrhea. Recommended treatment is focused on oral rehydration to replenish lost fluids and electrolytes.
The third most common cause of illness found by the Harvard study includes a group of mosquito-borne diseases: malaria, yellow fever, and dengue. Malaria risk in Brazil is highest in jungle, mining, and agricultural areas below 900 m altitude, especially within the Amazonia state. Anti-malaria tablets are available for travelers as a preventive measure. Although the CDC lists Brazil as a low-risk area, travelers can view the CDC “Malaria and Travelers” site for more information on higher-risk regions of the country, symptoms, and prevention. In addition, four World Cup cities are designated as risk areas for yellow fever: Belo Horizone, Brasilia, Cuiaba, and Manaus. Travelers visiting these areas are advised to get vaccinated against yellow fever. Both malaria and yellow fever can present with flu-like symptoms: fever, headache, chills, vomiting, body aches, and diarrhea.
Dengue poses yet another risk, although the Rio de Janeiro State Department of Health dismisses the threat of a dengue outbreak during the World Cup. Compared to last year, the risk of dengue is indeed much lower: there have been only 5,039 suspected cases in the state of Rio de Janeiro this year, while there were 178,765 suspected cases during the same period last year. However, some cities pose higher risks. Campinas, in the state of São Paolo, is facing the worst epidemic in its history with over 30,000 cases. The Portuguese national team is stationed in Campinas for the World Cup. Of all the cities in which games are being held, three northeastern cities—Recife, Fortaleza, and Natal—possess the highest risks for dengue transmission. Some basic preventive measures include wearing long sleeves and pants and using insect repellant to avoid mosquito bites, as no vaccine for dengue is available. In addition, researchers have developed an “early warning system” to assess the likelihood of dengue outbreaks during the World Cup.
The current outbreak of chikungunya—yet another mosquito-borne illness—in the Caribbean has caused some worry, especially due to the recent diagnosis of 6 imported cases of chikungunya in soldiers returning to São Paolo from a peace mission in Haiti. In addition, the transmission of indigenous (non-imported) cases in nearby countries such as Guyana is a cause for concern. If indigenous cases emerge in Brazil during the World Cup, international fans could carry it back to their home countries.
If the list of diseases wasn’t long enough already, here’s another one to add: measles. According to the Pan American Health Organization/World Health Organization (PAHO/WHO), 19 of the 32 countries participating in the World Cup reported measles cases in 2013. The U.S. alone has reported 397 measles cases this year. Measles is a highly contagious respiratory disease; symptoms include fever, rash, runny nose, and cough. In an effort to prevent the resurgence of measles in the Americas, PAHO recommends that World Cup fans get vaccinated against measles and rubella before traveling to Brazil.
The most important advice for travelers is to be aware of what diseases pose the highest risks in the areas they will be visiting. When going to the beach, bring proper footwear and avoid sitting on bare sand to prevent getting skin worms. Travelers should also practice safe eating and drinking habits such as choosing bottled water over tap water, making sure meat and seafood are cooked fully, and avoiding raw fruits and vegetables. If venturing to malaria and yellow fever risk areas, travelers should be prepared by taking anti-malaria tablets and getting a yellow fever vaccine. If it is too late to take these precautions, or when visiting areas where dengue is prevalent, basic measures can be taken to prevent mosquito bites: wearing long sleeves, pants, and insect repellant. The risk of contracting a disease brought by travelers from other countries is uncertain but always a possibility in mass gatherings like the World Cup. For this reason, fans should have received the measles, mumps, and rubella (MMR) vaccine prior to traveling and should take precautions against mosquitoes to prevent chikungunya, dengue, malaria, and yellow fever.
To all those travelers who are (or will be) in Brazil for the World Cup, be safe and enjoy some great soccer (football)!