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Biomédica 2011
Mayaro: a re-emerging arbovirus in Venezuela and Latin America Mayaro: un arbovirus re-emergente en Venezuela y LatinoamericaAbstract: Mayaro virus produces nonspecific, sublethal disease symptoms, often confused with dengue, but symptoms of arthalgias that can cause incapacitating disability. Outbreaks have been localized and sporadic in the Pan-Amazonia forest since its first isolation in 1954 (Trinidad and Tobago). The literature available is scarce, diverse and dispersed. Mayaro virus is an alphavirus, phylogenetically related to the Semliki forest antigenic complex. UNA and Mayaro viruses are the only viruses of this complex that have been isolated in the New World. Mayaro consists of single-stranded RNA of positive charge, length of 12kb, subdivided into genomic and subgenomic regions, which encode nonstructural and structural proteins respectively. Mayaro shows a great plasticity in vertebrate host infection, whereas high specificity in the family Culicidae (mosquitoes). Risk factors of infection are associated with forest areas of northern South America and the rainy season. Two genotypes of MAYV have been identified, L (Belterra, Brazil) and D (widely distributed in the Pan-Amazonia). The enzootic cycle is similar to the jungle cycle of yellow fever, which involves Haemagogus mosquitoes and monkeys as reservoirs. However the involvement of other secondary vectors and other hosts that may be important in spread of the virus cannot be ruled out. Humans may have high levels of viremia, and efficient experimental transmission has been demonstrated in Aedes aegypti, Aedes albopictus and Aedes scapularis, suggesting a significant risk to public health in urban, rural and peridomestic locations close to enzootic foci of Mayaro virus. El virus Mayaro produce una enfermedad de síntomas inespecíficos y sub-letales, frecuentemente confundida con dengue, con síntomas de artralgias que pueden generar incapacidad laboral. Los brotes han sido esporádicos y localizados en la región selvática de la Panamazonia posterior a su primer aislamiento en 1954 (Trinidad y Tobago). La información en la literatura es escaza, diversa y dispersa. Mayaro es un alphavirus filogenéticamente relacionado al complejo del virus del bosque de Semliki, siendo junto a UNA, los únicos virus de dicho complejo aislados en el nuevo mundo. Está conformado por ARN de cadena simple de carga positiva, longitud de 12kb con la región 42S y 26S, que codifican para proteínas no estructurales y estructurales. El virus Mayaro presenta gran plasticidad de infección en vertebrados y especificidad hacia la familia Culicidae (mosquitos) como vectores/hospedadores invertebrados. Los factores de riesgo están asociados a zonas boscosas
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