Spatio-temporal evolution of canine rabies in Tunisia, 2011-2016

Tunisia is an endemic country for dog mediated rabies. An increase in canine rabies cases during the last decade has been suspected. Since no studies have been conducted on rabies spatial distribution, the present work was focused on spatiotemporal evolution of rabies in Tunisia during the 2011-2016 period with a special focus on the reservoir species. Data collected concerned suspected dogs that originate from the whole country. Surveillance indicators such as positive fractions and number of suspected dogs received at the laboratory have been calculated. Spatiotemporal hotspots were then mapped, spatial and spatio-temporal analysis were carried out using discrete Poisson spatial model and space-time permutation models available in SaTScan9 software. The study revealed that an actual increase in canine rabies incidence occurred in Tunisia since 2012. Spatial and spatio-temporal analysis identified clusters centered in the North and in the Center East of the country. Spatio-temporal clusters were non overlapping, indicating that this spatial distribution is not fixed through time. A large heterogeneity in surveillance indicators such as number of suspected dogs was associated to the distance to the laboratory or to insufficient coordination between governorates.