Abstract & Commentary
Avoid real World Cup Fever: Prevention of Communicable Disease while visiting Brazil
Vector-borne diseases, such as malaria, may be acquired in parts of Brazil
By Philip R. Fischer, MD, DTM&H and Peter J. Holmberg, MD
Dr. Fischer is Professor of Pediatrics, Department of Pediatric and Adolescent Medicine, Mayo Clinic, and Dr. Holmberg is a Pediatric Resident, Mayo Clinic, Rochester, NY
Drs. Fischer and Holmberg report no financial relationships in this field of study.
Iliaki E, et al. Travel to Brazil: Analysis of Data from the Boston Area Travel Medicine Network (BATMN) and Relevance to Travelers Attending World Cup and Olympics. J Travel Med 2014;21(3):214-217
The 2014 FIFA World Cup and 2016 Summer Olympics will take place in Brazil and likely attract upwards of 600,000 international visitors each.1 While many gains have been made in the reduction of communicable diseases in this Latin American country, infectious diseases still pose a great challenge in many areas of Brazil. Malaria cases have decreased overall, but the annual incidence of dengue has increased over the last two decades, and transmission areas of yellow fever also have grown larger. Much of the morbidity and even mortality due to the infectious diseases found in Brazil are either vaccine-preventable or reduced by avoidance of mosquitoes, use of insect repellent, and/or the use of prophylactic medication.
The Boston Area Travel Medicine Network (BATMN), consisting of five travel clinics in the Boston area, reviewed 599 travelers who had destinations that included Brazil. A total of 85% received prescriptions for self-treatment of traveler’s diarrhea, and 39% received anti-malarial prophylaxis. Yellow fever and typhoid were the most commonly administered pre-travel vaccinations at 71% and 58% respectively. A total of 50% of travelers received Hepatitis A vaccination (and another 39% had previously received this vaccine) with 14% receiving influenza vaccination and 11% obtaining Hepatitis B pre-travel immunization. The most common risk prevention topics included vector-borne disease avoidance and fresh water exposure at 98% and 96%.
Brazil is a country with several vector-borne infection transmission zones, making initial pre-travel guidance difficult. Malaria — especially Plasmodium vivax but also some P. falciparum — is a disease with continued prevalence in Brazil, particularly in the Amazon region. However, most of the common areas of travel are without significant risk of transmission. Chemoprophylaxis is indicated for travelers whose itineraries include malaria-endemic parts of the country. Brazil has large regions that are yellow-fever endemic and pre-travel vaccination is indicated for all visitors except those visiting only eastern coast areas. Dengue fever is transmitted year-round via the vector mosquitoes Aedes aegypti and Aedes alboptictus and precautions should be taken against mosquitoes, including avoidance and the use of insect repellants. Furthermore, typhoid fever is present but much less common in Brazil and immunization may be indicated. While influenza remains the most common vaccine-preventable disease in travelers, most of the visitors to Brazil did not obtain the vaccine. However, the 2016 Olympics will coincide with peak influenza circulation.
COMMENTARY
Brazil is a culturally and environmentally diverse nation with significant natural beauty and resources. It has been selected as the host nation for the 2014 FIFA World Cup and the 2016 Summer Olympics/Paralympics and will undergo significant transformation in anticipation of over 1 million combined visitors to these two events. While communicable diseases remain one of the most significant causes of morbidity and mortality in visitors to Latin America, and particularly Brazil, the majority of infectious illnesses can be prevented with pre-travel vaccination or avoidance of vector-borne insects and appropriate repellants. As such, the Latin American Society for Travel Medicine (SLAMVI) has set forth guidelines for those traveling to Brazil.1
Given the prevalence of vector-borne illnesses including malaria, yellow fever, dengue, leishmaniasis, chikungunya, and Chagas disease, among others, education regarding the avoidance of mosquitoes and other insects (i.e., sandflies and Triatominae or "kissing bugs") is essential for those traveling to Brazil.1 While cases of malaria have been reduced dramatically since 2005, there were still almost 250,000 reported cases in Brazil in 2012. The majority of malaria in Brazil is due to Plasmodium vivax transmitted via the Anopheles mosquitoes; visitors to high-risk areas may need chemoprophylaxis depending on time of year. The second most prevalent vector borne-illness, yellow fever, is largely preventable with vaccination. Travelers to parts of the country where yellow fever is endemic should receive the immunization. Of concern recently has been the arrival of chikungunya virus, with the first case in Rio de Janeiro noted in 2010.2 Chikungunya is an arbovirus of the Alphavirus genus and has the same vector as dengue, the mosquito Aedes aegypti.2 The lack of vaccination and medication for dengue and chikungunya infections underscores the importance of mosquito avoidance measures, including screens, bednets, and insect repellants.
A 2013 review compared the efficacy of different types of repellent against several types of insects including Aedes, Anopheles, and Culex mosquitoes as well as Ixode.3 In regard to travel to Brazil, the most important insects are Aedes and Anopheles. Ae. aegypti was overall more difficult to repel than was Ae. albopticus. Regardless of species, Aedes mosquitoes were most effectively repelled with a DEET concentration of 20% or more. The 20% DEET was superior to other repellents, including IR3535, icaridin and citriodora. The profiles for the four repellents were similar in terms of repellency of Anopheles species.3 Insect repellents with high concentrations of DEET are also effective for the prevention of transmission of infections via sandflies.4
While Brazil is preparing for a massive influx of visitors, we must also prepare our patients before they travel. Pre-travel vaccinations for yellow fever, influenza, and hepatitis A as well as insect-avoidance measures including use of air conditioning, nets and insect repellants with 20% DEET, are important considerations for travelers to Brazil.
References
- Gallego V, et al. The 2014 FIFA World Cup: Communicable disease risks and advice for visitors to Brazil - A review from the Latin American Society for Travel Medicine (SLAMVI). Travel Med Infect Dis 2014;S1477-8939(14)00078-7.
- Albuquerque I, et. al. Chikungunya virus infection: report of the first case diagnosed in Rio de Janeiro, Brazil. Rev Soc Bras Med Trop 2012;45(1):128-129.
- Lupi E, et. al. The efficacy of repellents against Aedes, Anopheles, Culex and Ixodes spp. A literature review. Travel Med Infect Dis 2013;11(6):374-411.
- Centers for Disease Control and Prevention. Leshmaniasis- Prevention and Control. Available at: http://www.cdc.gov/parasites/leishmaniasis/prevent.html.
