Molecular and cellular evidence of natural Venezuelan equine encephalitis virus infection in frugivorous bats in Colombia.

BACKGROUND AND

aimVenezuelan equine encephalitis virus (VEEV) is an alphavirus that causes encephalitis with a high impact on public health in Latin America. However, only in Guatemala, Trinidad and Tobago, and Mexico have found antibodies in VEEV in bats, using immunohistochemistry, the sensitivity and specificity are improved; thus, it is better for demonstrating natural infection in bats as potential hosts. This study aimed to determine the presence of VEEV in tissues of frugivorous bats. MATERIALS AND

methodsA prospective descriptive cross-sectional study with a non-probabilistic sampling was carried out in 12 localities of Córdoba and Sucre area of the Colombian Caribbean. Two hundred and eighty-six bats were captured using fog nets, and the specimens according to taxonomic keys were classified. According to the Ethics Committee of the University of Córdoba, the bats were treated with analgesics and anesthetics. Blood samples were taken and then euthanized to obtain tissues and organs which were preserved in liquid N2 at -196°C. A portion of each organ was fixed in 10% buffered formalin for the detection of antigens by immunohistochemistry. Several pathological anatomy analyses were performed to determine the histological characteristics of tissue lesions of frugivorous bats naturally infected with the VEEV.

resultsOf the 286 bats captured, 23 species were identified. In samples of the brain, spleen, and lung of two frugivorous bats (2/286=0.70%)

conclusionA fragment of the nsP4 non-structural protein gene corresponding to the alphavirus was amplified. Two samples were positive (2/286=0.70%) in frugivorous bats;