Modelling canine leishmaniasis spread to non-endemic areas of Europe.

Abstract

Expansion of sandflies and increasing pet travel have raised concerns about canine leishmaniasis (CanL) spread to new areas of Europe. This study aimed to estimate the probability of CanL introduction and persistence following movements of infected dogs. Stochastic modelling was used to estimate the probabilities of (1) CanL infection during travels or imports of infected dogs (P inf and P infCA, respectively), (2) CanL persistence in a dog network with sandflies after introduction of an infected dog (P per), and (3) persistence in a CanL-free region (P per region) for N dogs moving between endemic and free regions. Different mitigation measures (MMs) were assessed. P inf [7.8%, 95% predictive interval (PI) 2.6-16.4] and P per (72.0%, 95% PI 67.8-76.0) were reduced by use of repellent, vaccine, prophylactic medication, and insecticide, in decreasing order of effectiveness. Testing and exclusion of positive dogs was most effective in reducing P per region for a small N. The spread of CanL to CanL-free areas with sandflies is thus likely, but can be reduced by MMs.