Oral Vaccination of Dogs as a Complementary Tool for Canine Rabies Control: The Thai Protocol

In Thailand, human and animal rabies incidence has decreased dramatically recently. Most rabies cases are among unvaccinated and free-roaming (owned or ownerless) dogs, underscoring that free-roaming dog vaccination is a key factor in controlling the disease. Oral rabies vaccination (ORV) has been intensively studied in dogs in Thailand. The concept of ORV is based on the following three components: (i) vaccines; (ii) baits; and (iii) distribution systems. A suitable, safe and efficacious vaccine candidate was identified and tested in local dogs. Furthermore, a bait readily accepted by the dogs was selected during field studies and further optimized. Finally, the handout-and-retrieve model for bait distribution was adapted to local conditions to reach a significant proportion of free-roaming dogs inaccessible to parenteral vaccination. Large-scale field studies in different settings have indicated that ORV may not only be feasible in Thailand but can also contribute to eliminating dog-mediated human rabies in other endemic countries.