RIFT-VALLEY FEVER EPIZOOTIC IN SMALL RUMINANTS IN SOUTHERN MAURITANIA(OCTOBER 1993) - RISK OF EXTENSIVE OUTBREAKS

Following the 1987 Rift Valley fever (RVF) epizootic/epidemic in south ern Mauritania, RVF antibody prevalence in small ruminants decreased s ignificantly from 1988 to 1992. In October 1993, at the end of the rai ny season, an active RVF virus transmission was detected in several lo cations of southern Mauritania in small ruminants, in association with an increase of abortions. RVF IgM and IgG antibodies were recorded re spectively in 65/390 (16.67 %) and 73/390 (18.72 %) animals. RVF IgM a ntibody prevalence was significantly higher in the greater than or equ al to 2 years old group (26.02 %) than in the 0.5 - <2 year old group (7.20 %) (p = 0.01). The enzootic maintenance of RVF virus is discusse d, as well as the risks of extension by traditional nomadic movements of herds.