Abstract:
Rabies, a fatal and vaccine-preventable disease, is endemic throughout Africa. In 2016,
a rabies outbreak occurred in black-backed jackals (Canis mesomelas) along the
western boundary of Gauteng Province, South Africa. We investigated the possible
drivers of the 2016 outbreak and established its origin. Using spatio-temporal locations
of cases, we applied logistic regression and Geographic Information System techniques
to investigate environmental covariates driving occurrences of emerging rabies cases in
Gauteng Province. About 53.8% of laboratory-confirmed lyssaviruses in Gauteng
Province in 2016 originated from jackals. Phylogenetic trees reconstructed from a partial
region of the glycoprotein gene of these and historical rabies viruses (RABVs)
demonstrated the lyssaviruses to be of canid origin with 97.7% nucleotide sequence
similarity. The major cluster comprised jackal RABVs from the 2012 KwaZulu/Natal
outbreak and the 2016 outbreak in Gauteng Province. The second cluster was
composed of both jackal and dog RABVs. Both clusters correlated with independent
RABV introductions into Gauteng by dogs and jackals, respectively. This study
demonstrated an expansion of a jackal rabies cycle from north-west Province into
Gauteng Province during the 2016 dry period, as jackals ranged widely in search for
food resources leading to increased jackal-dog interactions, reminiscent of the intricate
links of domestic and wildlife rabies cycles in South Africa.
