Arthropod-Borne viral Diseases in Peru

RESUMO

Arthropode-Borne viral diseases have been a significant cause of morbidity and mortality for several decades in Peru. Epidemics and epizootics of Venezuelan equine encephalitis (VEE), subtype IAB virus occurred among humans and equine at intermittent intervals from 1925 through 1973 along the Pacific coastal plains, extending southward from the most northern Departament of Tumbes to the Departament of Ica. While the VEE IAB virus has not been detected since 1973, several isolates of VEE ID and an isolate VEE IIIC were obtained during 1971 and 1975 from mosquitoes and/or sentinel hamster in Quistococha, northeastern Amazon region. In 1994, the first human cases, associated with VEE virus ID were diagnosed among Peruvian soldiers near Pantoja, northern Amazon region, and during 1995, primarily among students and military personnel in Iquitos, northastern Amazon region. As early as 1913 , a disease resembling yellow fever was recognized in the Amazon region Peru. Outbreaks of this disease have continued to occur, apparently at annual interval, with the most recent and the largest sylvan outbreak ever recorded in Peru being documented during 1995 along the eastern foothills of the Andes Mountains. In 1990, dengue (DEN) 1 and DEN4 were first isolated in Peru during an outbreak of DEN fever among residents of the city of Iquitos, northeastern Amazon basin region. Seroepidemiological and case surveillance studies conducted 1992 through 1995 documented that DEN 1 continued to cause cases of DEN fever in Iquitos, and in 1995, an outbreak was associated with the introduction of DEN 2 into the community. Outbreaks of DEN fever, associated with DEN 1 occurred during 1994 and 1995 in the northern coastal cities of Tumbes and Piura, and in Pucallpa, Amazon basin region. In 1995, the first isolations of DEN 2 were obtained from febriles cases in Tumbes, Piura and Pucallpa. Although 2 serotypes of DEN were associated with human infection, none of the cases presented with hemorragic manifestations. The first isolations of Oropouche (ORO) fever virus were obtained during 1992 from febrile patients in Iquitos. The virus was isolated during 1994 from febrile cases and serological results revealed that ORO was the cause of an outbreak in the southeastern Amazon region. A single isolate of ORO virus was obtained during 1995 from a febrile patient in Iquitos