A MOLECULAR EPIDEMIOLOGIC-STUDY OF RABIES VIRUS IN CENTRAL ONTARIO AND WESTERN QUEBEC

Rabies persists in Ontario wildlife in two predominant species: the re d fox (Vulpes vulpes) and the striped skunk (Mephitis mephitis). A pro tocol applying reverse transcription/polymerase chain reaction (RT/PCR ) and restriction endonuclease analysis (REA) to the rabies virus nucl eoprotein gene was previously reported by Nadin-Davis et al. (Journal of General Virology 74, 829-837, 1993) to be useful for discrimination of rabies virus variants in Ontario. Four main types, which showed no host species specificity but which did exhibit different geographical distributions, were identified. Between 1989 and 1992 an area north a nd west of the city of North Bay experienced unusual and substantial r abies activity. In this report we describe the use of these molecular techniques to investigate the epidemiology of this recent rabies outbr eak in central Ontario. It is shown that two of the four previously id entified variants had invaded this region from the south and east, but in addition viruses very closely related to arctic isolates of rabies virus were found. The nucleoprotein and glycoprotein genes of this ar ctic type were sequenced and compared to those of its more southerly n eighbours.