Determinants of Vaccination Coverage and Consequences for Rabies Control in Bali, Indonesia

Area of Science:

• Veterinary Public Health
• Epidemiology
• Zoonotic Disease Control

Background:

• Maintaining high vaccination coverage is essential for effective rabies control in dog populations.
• Dog population turnover and challenges in mass vaccination campaigns can hinder sustained high coverage.
• Previous island-wide vaccination campaigns in Bali have shown promise but low-level rabies circulation persists.

Purpose of the Study:

• To estimate dog population size and assess rabies vaccination coverage in Bali.
• To identify demographic factors influencing vaccination status in owned and free-roaming dogs.
• To inform strategies for achieving higher vaccination coverage and rabies elimination.

Main Methods:

• Door-to-door (DTD) questionnaire surveys of 10,352 dog-owning households.
• Photographic mark-recapture surveys using line transects to observe free-roaming dogs.
• Analysis of vaccination coverage by age (adult vs. juvenile) and dog confinement status (confined vs. free-roaming).

Main Results:

• Owned dog vaccination coverage was high in adults (91.4%) but low in juveniles (43.9%).
• Juvenile dogs and free-roaming owned dogs had significantly higher odds of being unvaccinated.
• Vaccination coverage estimates varied significantly between household surveys (83.6%) and transect surveys (30.9%).

Conclusions:

• While owned dog vaccination coverage is generally high, targeting juveniles and free-roaming dogs is critical for rabies elimination in Bali.
• Future vaccination campaigns must prioritize suburban and rural areas and ensure pup vaccination.
• Development of effective, long-lasting methods for marking vaccinated animals is needed to reassure communities.