SEROLOGICAL EVIDENCE OF CIRCULATION OF ALPHAVIRUS (VENEZUELAN EQUINE ENCEPHALITIS VIRUS AND UNA VIRUS) IN PARAGUAYAN POPULATION (2012-2013)

CARDOZO FM; KONIGHEIM B; ALBRIEU LLINÁS G; RIVAROLA ME; AGUILAR J; QUAGLIA A; ROJAS A; PÁEZ M; GUILLÉN Y; DIAZ A; VALLEJOS MA; HEREBIA L; RECALDE ML; CONTIGIANI MS; MENDOZA LP

Pirenopolis

Congreso; XXVII Congresso Brasileiro de Virologia; 2016

Sociedade Brasileira de Virologia

The Alphavirus genus includes viral species that produce encephalitis in horses and humans, as well as febrile illness with rash and arthralgia in humans. Among the producers of encephalitis are found epizootic subtypes of Venezuelan Equine Encephalitis Virus (VEEV) complex. This complex also includes enzootic subtypes that, although they doesn?t cause disease in horses (except subtype IE), it can cause them in humans. The Rio Negro Virus (RNV VEEV subtype VI), that circulates in Argentina, where it was associated with undifferentiated febrile illness. The Mayaro (MAYV), Chikungunya and Una (UNAV) viruses belong to Semliki Forest viruscomplex, being recognized MAYV activity in Central and South American countries, with recent activity in Mexico.In addition, the UNAV has been detected in several countries in South America. The present study aimed to determine RNV, MAYV and UNAV seroprevalence by plaque reduction neutralization test (PRNT) in 650 samples of Paraguayan individuals mainly from Central Department, period 2012-2013.Seroprevalence for RNV was 5.8%, and for UNAV it was 0.46%. No neutralizing antibodies against MAYV were detected in the studied population. The 50.1% of neutralizing antibody titers against RNV were high (equal to or greater than 1/640), which would indicate a recent virus circulation. Inaddition, it was observed a seroprevalence increment tendency as age increases, which suggests an endemic behavior of this virus. These results represent the first indication of RNV and UNAV circulation in Paraguay, and these data will serve as the basis for future studies to search potential hosts and vectors of these viruses in the region.