More common infections in travelers include dengue, gastrointestinal infections, and malaria. Chronic or latent infections in immigrants (and long-term residents) include tuberculosis, schistosomiasis, leishmaniasis, Chagas’ disease, cysticercosis, and intestinal helminth infections, including strongyloidiasis.
Vector-borne infections: Malaria is widely distributed, but the risk to travelers is low in most areas. Vivax malaria predominates in many areas. Dengue outbreaks have increased in the past decade, and infections occur in travelers. Yellow fever causes sporadic cases and outbreaks. Cases have been reported since 2000 from Bolivia, Brazil, Colombia, Ecuador, Peru, and Venezuela. Aedes aegypti infests all these countries, including urban areas, placing them at risk for introduction of yellow fever (and dengue). Fatal yellow fever has occurred in unvaccinated travelers. Other vector-borne infections include rickettsial infections (murine typhus and spotted fever due to Rickettsia rickettsii and R. felis), relapsing fever (the tick-borne form is widely distributed; the louse-borne form occurs primarily in the highlands of Bolivia and Peru), and Venezuelan encephalitis. Oropouche fever is a common arboviral infection, especially in the Amazon ba-sin. Leishmaniasis has increased in recent years; foci of transmission of cutaneous leishmaniasis are found throughout the region; visceral leishmaniasis is found primarily in Brazil. American trypanosomiasis (Chagas’ disease) has been widespread in poor, rural areas, but transmission has been interrupted or slowed in many areas (e.g., Brazil) through eradication programs. Onchocerciasis is endemic in focal areas of Brazil, Colombia, Ecuador, and Venezuela; eradication efforts are in progress. Bartonellosis is found in the mountain valleys of Peru (largest endemic focus), Ecuador, and southwestern Colombia (at altitudes of 600-2800 meters). Lymphatic filariasis is endemic in Guyana and in focal areas of Brazil and in parts of northeastern South America. Myiasis occasionally occurs in travelers.
Food- and waterborne infections: Gastrointestinal infections in travelers are caused by bacteria, viruses, and parasites. Hepatitis A risk is widespread. Cholera was widespread in South America in the 1990s; only Brazil, Colombia, and Ecuador reported infections in 2005. Typhoid fever, brucellosis, and amebic liver abscesses are occasionally seen in travelers. Fascioliasis is highly endemic in some areas, especially in Bolivia, Ecuador, Peru, and Venezuela, but risk is low for the usual traveler. Paragonimiasis is endemic in Ecuador and Peru and occurs sporadically in other countries; infections are rare in the usual traveler.
Airborne and person-to-person transmission: The annual incidence rate of tuberculosis per 100,000 is estimated to be 100-300 in Peru, Ecuador, Bolivia, and Guyana and 50-100 or less in the rest of the region. Multidrug resistance has been a problem, especially in Peru and Ecuador, where the rate of multidrug resistance is 3%-6% among new cases (17). Leprosy is highly endemic in some focal areas (e.g., high prevalence in the Amazon and parts of the Andes). Prevalence in Brazil was 46 per 100,000 population in 2004.
Sexually transmitted and blood-borne infections: Prevalence of HIV in adults is estimated to be 0.1% -<1% in most of the region, but the prevalence is higher in Guyana and Suriname (1%-<5%). The prevalence of chronic infection with hepatitis B exceeds 8% in Peru, northern Brazil, and southern Colombia and Venezuela and is 2%-7% in the rest of the region. Hepatitis D has caused epidemics of fulminant hepatitis in the Amazon Basin. HTLV-I is found especially in areas adjacent to the Caribbean, including Colombia, Venezuela, Surinam, Guyana, and Brazil.
Zoonotic infections: Rabies is found throughout the region; vampire bats transmit infection in some areas and have been responsible for outbreaks of human rabies in Peru, Venezuela, and Brazil. Hantavirus pulmonary syndrome caused by hantaviruses with rodent reservoirs has been documented in Bolivia, Brazil, and Paraguay; these viruses may be more widely distributed. Other rodent-associated viruses include Machupo virus,* which causes sporadic infections in rural northeastern Bolivia, and Guanarito virus in Venezuela. Plague* has been reported from Bolivia, Brazil, Ecuador, and Peru since 1990 (most cases are from Peru). Echinococcosis* is endemic in cattle-grazing areas of Ecuador and other countries; the risk to travelers is low.
Soil- and water-associated infections: Endemic foci of schistosomiasis (Schistosoma mansoni) are found in Brazil, Venezuela, and Suriname. Buruli ulcer (Mycobacterium ulcerans) is endemic in French Guyana; a few cases have been reported from other countries (e.g., Peru and Suriname). Risk of leptospirosis* is widespread in tropical areas; outbreaks have followed flooding. Histoplasmosis has been reported from all countries in the region, and paracoccidioidomycosis is endemic throughout the area, with the highest transmission in Peru, Ecuador, Colombia, and Brazil. Coccidioidomycosis is more focal in distribution with endemic areas in Brazil, Colombia, Paraguay, and Venezuela.
Other hazards: Venomous snake bites, injury from motor vehicle accidents, and high altitude-related illness in the Andes occur. Screening of blood before transfusion is inadequate in many hospitals.