Rabies epidemiology, prevention and control in Nigeria: Scoping progress towards elimination

Background Human rabies remains a significant public health problem in Africa with outbreaks reported in most countries. In Nigeria-the most populous country in Africa-rabies causes a significant public health burden partly due to perennial obstacles to implementing a national prevention and control program. Methods We conducted a scoping review using standard Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify and select published articles from Nigeria during 1978-2020 reporting on rabies virus infections (human, canine, livestock, and wildlife), canine bites, knowledge, attitudes and practices (KAP) surveys on rabies and canine ecology studies. We extracted information on study location, year and additional details of each study such as rabies prevalence, general characteristics of offending dogs, dog vaccination status and health-seeking behaviours. Findings Between 1978 and 2020, 90 published articles met our inclusion criteria. The prevalence of rabies virus antigen detection varied between 3% and 28%, with more studies in the north. Most bites were unprovoked from dog bite studies (36.4%-97%), by dogs with low vaccination rates (12-38%). A more significant proportion of biting dogs were owned (31-90%). Laboratory confirmation for biting was available for only a small proportion of studies (6%; n = 2/32). Of the dogs surveyed during ecology studies, indigenous dogs accounted for the majority (62-98%), used mostly for security purposes (52-98%), with the vaccination rate between 15% and 38% in most states. Studies conducted in areas distant from rabies diagnostic facilities accounted for more human rabies cases and fewer dog rabies cases. Conclusion Significant improvements are necessary to achieve the elimination of human rabies mediated via dogs by 2030. Author summary Rabies remains one of the deadliest zoonoses known to humanity since antiquity, resulting in tens of thousands of human deaths each year, mostly in African and Asian countries. Mass dog vaccination, enhanced surveillance, improved access to PrE (Pre-exposure prophylaxis) and PEP (Post-exposure prophylaxis) to at-risk groups, enforcement of responsible dog ownership and public education are keystones to rabies prevention and control. Since the first reported case in Nigeria during 1912, rabies has continued to take its toll on human and animal lives. However, gross underreporting due to a frail health care infrastructure, deficient reporting systems, and misdiagnosis with neurological diseases further complicated by socio-cultural practices have resulted in a lack of empirical data to support rabies prioritization, per the global target of 2030. We used the standard PRISMA guidelines to select Nigerian rabies studies between 1978 and 2020. Rabies risk, coupled with welfare concerns identified in this study, demonstrates the need for continued advocacy towards legislation prohibiting the dog trade in Nigeria and elsewhere. The high-risk community groups identified in this review (i.e., children, butchers, and adult males) need to be educated on response to dog bite exposure to reduce the impact of this invariable fatal but preventable disease. Moreover, there is a need for mandatory dog vaccination and implementation of a national rabies program to attain the World Health Organization (WHO) recommended vaccination coverage of at least 70%. We unravel the need to establish rabies diagnostic centres in the country's six geopolitical zones. Local inclusion of dog bite occurrence by Disease Surveillance and Notification Officers (DSNOs), with related community surveillance tools, can help in rabies/dog surveillance. In addition, there is a need for investment into pathogen discovery by enhancing laboratory-based surveillance for wildlife rabies, understanding its potential role in in Nigeria and the need for quantitative research to understand the various risk factors for disease perpetuation.

Automated summary

Rabies remains a significant public health problem in Nigeria, with studies showing a prevalence of rabies virus antigen detection varying between 3% and 28%, and most biting dogs being unvaccinated, necessitating the implementation of more measures for prevention and control of rabies.