Canine rabies in Vientiane Prefecture, Lao PDR : vaccination status and protection level

Abstract: Rabies is a fatal viral disease that is primarily transmitted to humans by domesticated dogs. Canine rabies is estimated to be accountable for the death of 59,000 humans each year in the world and if post-exposure treatment is not initiated, death usually occurs within a month after first signs of symptoms. Rabies is however preventable through engaging the society and educating regarding rabies and the importance of post-exposure treatment. Another important measure is rabies vaccination of dogs. Research show that if 70% of the canine population is vaccinated against the rabies virus, it is enough to prevent human cases of dog-mediated rabies, which is why many endemic countries conduct mass dog vaccination campaigns. The continents with most human cases of canine rabies are Africa and Asia. In this study, the vaccination status of dogs in Vientiane Prefecture in Lao PDR was investigated. Laos is a country located in Southeast Asia, with boarders to Cambodia, Thailand, Myanmar, China, and Vietnam. Every year, there are two to four human deaths due to rabies in Laos. To investigate the vaccination status, a survey was conducted in Vientiane Prefecture where dog owners were asked questions regarding the dog, the dog’s living situation and vaccination status. Serum was then collected from the dogs and analysed for rabies virus neutralizing antibodies using the enzyme-linked immunosorbent assay (ELISA) test. The test distinguishes the samples that have detectable rabies virus neutralizing antibodies, which then are considered positive for antibodies. It also detects the samples that has an antibody level greater than 0.5 IU/ml. These dogs are considered as protected against rabies. Our results showed that 28.38% of dogs included in the study had detectable antibodies against rabies, and 13.19% of the sampled dogs were protected against rabies. When asking the owners about any previous vaccinations, the answers were deviant from the results. The study also showed that more dogs in the districts closer to Vientiane capital city were vaccinated compared to dogs living in districts further away. The results in this study highlights the deficiency regarding rabies vaccination among dogs in Vientiane Prefecture and further mass dog rabies vaccination campaigns need to be conducted to make Lao PDR free of dog-mediated human deaths of rabies.