Vector -borne viral diseases in the Amazonian rain forest of Ecuador

• Main Author: Izurieta, Ricardo O
• Format: Dissertation
• Language: English
• Published: ProQuest Dissertations & Theses 01.01.2000
• Subjects: Immunology; Microbiology; Public health; Rainforests; Viral infections; Ecuador
• ISBN: 0599999608; 9780599999602

Population movement has been an important factor in determining the spread of viral diseases in the New World, including the Amazonian rainforest. In July and August of 1997, an epidemic outbreak of an unknown hemorrhagic fever was detected in the Pastaza Province in the Ecuadorian rainforest. The outbreak appeared among military personnel who were detached to the frontier with Peru during an armed conflict between Ecuador and Peru. A multidisciplinary team was mobilized by the Ecuadorian Armed Forces to investigate and control the outbreak. A cross-sectional seroepidemiological survey was conducted in the military personnel of a jungle garrison and its detachments located in the Amazonian rainforest of Ecuador. The cross-sectional study employed interviews and seroepidemiological methods. Humoral immune response to yellow fever, Mayaro, Venezuelan equine encephalitis, Oropouche, and dengue 2 infection was assessed by evaluating IgM- and IgG-specific antibodies. During the outbreak research, a yellow fever attack rate of 13% (44/341, with 3 fatal cases) was observed among military personnel who had not been immunized prior to their detachment in the Amazon rainforest. Clearing the rainforest and being in the detachments were significantly associated with yellow fever infection. We also evaluated the association between protective immunity from cross-reactive dengue antibodies with yellow fever infection and with severity of the disease. Presence of dengue antibodies among individuals with yellow fever was observed in 77.3% cases from the coastal region where dengue is endemic, 14.3% cases from the Amazon, and 16.7% cases from the Andean region. (Abstract shortened by UMI.)