The impact of an African swine fever outbreak on endemic tuberculosis in
wild boar populations
Abstract
Animal tuberculosis (TB) is a widespread infectious disease caused by
the Mycobacterium tuberculosis bacteria belonging to the
Mycobacterium tuberculosis complex (MTC) that can persist in
reservoir wildlife hosts. Wild boar (sus scrofa) are a key
reservoir for MTC and an increasing trend in wild boar density is
expected to lead to an increase in TB prevalence with spill-over to
livestock. MTC infection is presently controlled through a variety of
strategies, including culling. African swine fever (ASF) is a virulent,
viral infection which affects wild boar and is spreading across Eurasia
and Oceania. ASF infection leads to near 100% mortality at the
individual level, can cause a dramatic decrease in population density
and may therefore lead to TB control. In this study we develop a
mathematical model to examine the impact of ASF introduction into a wild
boar population that supports endemic TB. Our model results indicate
that an ASF infection will reduce wild boar population density and lead
to a decrease in the prevalence of TB. If ASF persists in the local host
population the model predicts the long-term decline of TB prevalence in
wild boar. If ASF is eradicated, or fades-out in the local host
population, the model predicts a slower recovery of TB prevalence in
comparison to wild boar density after an ASF epidemic. This may open a
window of opportunity to apply TB management to maintain low TB
prevalence.