[Rabies virus isolation in the salivary glands of insectivorous bats]

This study determined the presence of the rabies virus in salivary glands, as well as its titre and antigenic characterisation and the level of exposure to the virus from contact between domestic animals and humans. Twenty-six positive brain samples were selected, 80% of which were from the Brazilian free-tailed bat, Tadarida brasiliensis, corresponding to the period 1999-2005. Antigenic characterisation was conducted on a panel of 19 monoclonal antibodies targeting the rabies virus nucleoprotein supplied by the Centers for Disease Control and Prevention in Atlanta in the United States of America. The results revealed a high percentage of isolations in salivary glands (76.9%). Their average titres were compared in a batch of positive samples of brain and salivary glands, giving values of 4.75 and 3.81 respectively (expressed as log LD50/0.03 ml). The isolated viruses corresponded principally to variant 4 associated with T brasiliensis and variant 6 associated with the hoary bat, Lasiurus cinereus, and the red bat, L. borealis, and their respective subvariants. The level of exposure in domestic animals and humans was 50% during the period under study.