Rabies is one of the oldest zoonotic infectious diseases in medical history [1, 2] caused by a virus belonging to the Lyssavirus genus [2]. Known as a neglected disease, rabies is transmissible to humans as well as domestic and wild animals [3]. It is usually transmitted invasively through saliva that penetrates a wound (after a bite, scratch or lick). The clinical manifestation of rabies consists of encephalitis with severe and distinct symptoms that inevitably result in death. Dogs are primarily responsible for most human rabies and account for up to 99% of human transmission in Asia and Africa [4, 5], making a major public health problem in most developing countries (with an estimated 59,000 deaths per year globally). The burden of the disease is particularly huge in the tropical and subtropical regions of Africa and Asia [1, 2] with an estimated 44% of human rabies cases occurring in Africa with 7,000 deaths yearly in the central part of the continent [6]. The World Health Organization (WHO) estimates the number of deaths from rabies in urban areas at 2 per 100,000 and in rural areas of Africa at 3.6 per 10,000 [7].
The burden is mostly higher among rural communal areas with large stray dog populations and low dog vaccination coverage [8–11]. Poverty and poor awareness of rabies are generally associated with an increased vulnerability to the disease and are, consequently, major obstacles in prevention and control, especially in rural areas [12, 13]. A general understanding of dog behaviour, responsible pet ownership, appropriate health service-seeking behaviour following dog bites and rabies prevention are all crucial in rabies control and necessary to be addressed by awareness-raising interventions to reduce vulnerability and exposure [3].
Like in many other countries, rabies is a notifiable disease in Cameroon since 2001 [17]. As such, a reliable and sensitive epidemiological surveillance and reporting system must be in place to facilitate regular data collection and reporting of animal exposures. Such surveillance is often inadequate and official reporting of human and animal disease incidence remains unsatisfactory and incomplete. It is increasingly recognized that available data underestimate the true incidence of rabies and that, in many cases, the true quantitative burden of the disease is best represented by estimates [6].
According to the same study, the actual number of rabies cases could be 160 times higher than the number of reported cases if epidemiological surveillance had been effectively implemented. Many dog bite cases are not identified or reported; people with rabies most often die at home without being diagnosed. Cases diagnosed in hospitals are partially reported, and victims of bites do not receive appropriate PEP due to a lack of awareness among health workers, or due to the expensive costs [7, 14].
In 2018, the Tripartite and Global Alliance for Rabies Control launched the Global Strategic Plan (GSP) to end human deaths from dog-mediated rabies by 2030 [15]. However, the epidemiology of rabies from most West and Central African countries remains poorly defined, making it difficult to assess the overall rabies situation and progress towards the 2030 goal [15].
Cameroon remains endemic for rabies, where dogs are the main vectors, but there is no national rabies control action plan despite the inclusion of the One Health approach in rabies surveillance (Fig. 1) in ministerial guidelines. In 2015, a total number of 5878 dog bites cases were recorded in the country [16]. Yet, these data are still fragmentary and certainly do not reflect the reality of the burden of this disease [16]. In the absence of exhaustive epidemiological data, the health it may be difficulty for the authorities to perceive the severity of the disease’s implications on public health. This might result into paying least attention to the disease and, and therefore, not allocating sufficient resources to rabies control efforts [7].
A study reported that in the West Cameroon Region, most animal exposures and human rabies cases were not reported [17]. Moreover, surveillance was mostly passive and incomplete, and no case report forms, or rabies case registers were available. Subsequently, the rabies surveillance network in the West Cameroon Region was strengthened with 337 fully documented animal exposures and 143 undefined exposures recorded in the studied Health Districts, for a total of 480 exposures [17]. Similarly, a higher number of animal exposures were also recorded in 2015 and in the first 6 months of 2016. These data from approximately 78% of the population in the West Cameroon region, are 8–10 times higher than the 57 exposures previously reported for the whole region in 2013 [16].
A comparative review of the rabies epidemiological surveillance data found in the outpatient register and those reported in the district health Information Software 2 (DHIS2) – the main medium for notification of cases, in the West region of Cameroon from 2019 to 2021 shows a clear discrepancy in all the Health Districts of the region, between the surveillance data found in the outpatient registers and those reported in the DHIS 2. In addition, the reported data were strongly underestimated [18].
Nevertheless, since the beginning of 2017, the proportion of data reported to the surveillance system has decreased statistically compared to the previous two years. This could be related to the under-reporting of dog bite cases in the surveillance system in the districts, which indicates the lack of an effective surveillance system [16]. Hence, this research aimed at analyzing the inadequacies in the collection and dissemination of rabies surveillance data in the West Cameroon region.