Frequency of antibodies to arenaviruses in wild rodents captured in the Midwest, Southeast and Southern regions of Brazil

Abstract

Viral hemorrhagic fevers caused by arenavirus are severe emerging zoonosis. Humans are
mainly infected accidentally by mucosal exposure to aerosols formed from excreta from
rodent reservoirs. In reservoirs, the presence of antibodies may indicate movement in a viral
population in a specific region, and this data can be used as an indicator for further investigation
using molecular techniques. To date the natural reservoir of the virus species Sabiá etiological
agent of Brazilian hemorrhagic fever was not detected. In order to broaden the search regions
by wild rodent species involved in the transmission of arenaviruses 2245 blood samples from
rodents collected between 1998 and 2008, randomly selected, were analyzed by ELISA for
detection of specific IgG antibodies arenaviruses. A total of 2230 samples had non-reactive
results, 12 presented reactive results and 3 had indeterminate results. The seropositive
species were Necromys lasiurus 0,6% (6/1012), Calomys tener 1,1% (2/187), Calomys
callosus 2,1% (2/94), Akodon sp 0,3% (2/723). We obtained a positive sample from a sample
from the municipality of Campo Alegre de Goiás; five samples from the municipality of
Bodoquena, Mato Grosso do Sul; and in six samples from the municipalities of Espírito Santo
do Pinhal, Nuporanga and Mogi das Cruzes, São Paulo. The municipalities of Campo Alegre
de Goiás, Bodoquena, Espírito Santo do Pinhal defined to expand the analyzes with new field
expeditions and biological samples collection aiming at the research of viral circulation.
Hemorrhagic fevers caused by arenaviruses are endemic pathologies occurring in restricted
geographical areas, but rodent’s reservoirs have wide geographic distribution. Search the
circulation of these viruses in rodents captured in their natural habitat, it is important to
understand the relationship of these reservoirs with susceptible host. So far, there are not
confirmed cases of the disease and viral detection in rodents, we emphasize the need for more
eco epidemiological surveillance studies to identify which species of rodents, for instance in
Brazil, can be natural reservoirs of arenavírus. With data in this study we hope to cooperate
with surveillance and prevention of this zoonosis.