Vectors and Natural Reservoirs of Oropouche Virus in the Amazon Region

Abstract

Abstract : Current efforts attempt to elucidate the endemic and epidemic cycles of Oropouche (ORO) virus. This virus cause disease in man generally of about 7 days duration, with some patients severely ill, occasionally to the point of prostration. This disease has been reported to cause large scale epidemics in urban areas of northern Brazil. Accomplishments included in this report with regard to ORO virus have been divided into two major categories; studies on the epidemic cycle, and studies on the endemic cycle. Under the category studies on the epidemic cycle, conclusive data are presented which establish the midge, Culicoides paraensis, as the primary epidemic vector of ORO virus. Subsequent sections present results of investigations of the basic biology of this midge. A second section of studies on the epidemic cycle of ORO virus deals with man as the principal vertebrate host in the epidemic cycle. Here evidence is presented which indicates that, when infected, man circulates ORO virus in sufficient titer to infect feeding C. paraensis. Finally, results of an epidemic of ORO virus disease which occurred in and around Tome, Acu, Para, Brazil are reported.