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Additional file 2. Vaccination coverage estimates. Estimates for each district for each year during which vaccination campaigns were undertaken. Details of the timings of the vaccination campaign are given for each year.

Additional file 3. Results of generalized linear models for the incidence of probable domestic dog rabies cases from models containing the mean domestic dog vaccination coverage from two years before cases occurred. The 95% confidence intervals for the estimates are shown in square brackets [].

Additional file 5. Results of generalized linear models for the incidence of probable jackal rabies cases from models containing the mean domestic dog vaccination coverage from two years before cases occurred. The 95% confidence intervals for the estimates are shown in square brackets [].

Additional file 1. Location of the probable animal rabies cases used within the subset analysis. Probable animal rabies cases are shown as black diamonds and include all species. The cases considered within the subset analysis are those located in the region outlined in blue. All cases included within the subset are within 10 km of another case.

Additional file 4. Results of generalized linear models for the incidence of probable domestic dog rabies cases from models containing the mean domestic dog vaccination coverage from three years before cases occurred. The 95% confidence intervals for the estimates are shown in square brackets [].

Additional file 6. Results of generalized linear models for the incidence of probable jackal rabies cases from models containing the mean domestic dog vaccination coverage from three years before cases occurred. The 95% confidence intervals for the estimates are shown in square brackets [].

Objective Using active surveillance approaches to investigate the transmission dynamics of rabies on Pemba Island and across Southern Tanzania, whilst a large-scale dog vaccination program was underway 1 , to gain a greater understanding of the dynamics of infection as the disease is driven towards elimination. Introduction Rabies is endemic in Tanzania and has circulated on Pemba Island since the late 1990s. In 2010, an elimination programme was initiated in Southern Tanzania to demonstrate that human rabies deaths can be eliminated through mass dog vaccinations. We used active surveillance approaches 2 to investigate the dynamics of rabies across the area where this programme was implemented. Methods Government census data and post-vaccination transects were used to estimate the dog population and coverages achieved by vaccination campaigns. Routine surveillance of animal bite injuries using a mobile phone-based surveillance system 3 and active contact tracing were used to identify animal rabies cases and human exposures. Epidemic trees were constructed using spatiotemporal distances between cases and used to estimate the effective reproduction number (R e ). We examined factors affecting rabies incidence and transmission using generalized linear mixed models. Results We estimated a small dog population of 4095 and low dog:human ratio on Pemba (1:105). Overall island-wide vaccination coverage increased from 16.8% in 2011 to 68.2% in 2014. We found a further 48 human exposures (343%), who either were not reported or did not obtain post exposure prophylaxes (PEP). Routine surveillance was found to detect less than 10% (~8.75%). There was a rapid decline in cases detected on Pemba, from 42 before mass dog vaccinations were implemented in 2011, to 2 cases in 2014 (Figures 1). Since May 2014, no rabies cases have been detected. Similarly, R e declined from 1.02 to 0 and a significant relationship was found with rabies cases decreasing with increasing vaccination coverage ( p = 0.013, Figure 2). Across seven other districts on the Tanzanian mainland we also observed major declines in rabies cases with very few cases of rabies in dogs detected in 2016 (Figure 3). Conclusions We conclude that rabies has been eliminated from domestic dog populations on Pemba over the five years since vaccination campaigns have been implemented. Continued surveillance and investigations of any bite incidents are therefore needed to ensure any subsequent incursions are controlled and freedom from rabies is maintained. On the Tanzanian mainland, it has taken longer to control rabies, however trajectories look promising with several districts close to eliminating the disease. However, detection of some wildlife cases in the last 12 months in these districts indicates the need to further investigate remaining foci and the role of wildlife in maintenance.

Rabies can be eliminated by achieving comprehensive coverage of 70% of domestic dogs during annual mass vaccination campaigns. Estimates of vaccination coverage are, therefore, required to evaluate and manage mass dog vaccination programs; however, there is no specific guidance for the most accurate and efficient methods for estimating coverage in different settings. Here, we compare post-vaccination transects, school-based surveys, and household surveys across 28 districts in southeast Tanzania and Pemba island covering rural, urban, coastal and inland settings, and a range of different livelihoods and religious backgrounds. These approaches were explored in detail in a single district in northwest Tanzania (Serengeti), where their performance was compared with a complete dog population census that also recorded dog vaccination status. Post-vaccination transects involved counting marked (vaccinated) and unmarked (unvaccinated) dogs immediately after campaigns in 2,155 villages (24,721 dogs counted). School-based surveys were administered to 8,587 primary school pupils each representing a unique household, in 119 randomly selected schools approximately 2 months after campaigns. Household surveys were conducted in 160 randomly selected villages (4,488 households) in July/August 2011. Costs to implement these coverage assessments were $12.01, $66.12, and $155.70 per village for post-vaccination transects, school-based, and household surveys, respectively. Simulations were performed to assess the effect of sampling on the precision of coverage estimation. The sampling effort required to obtain reasonably precise estimates of coverage from household surveys is generally very high and probably prohibitively expensive for routine monitoring across large areas, particularly in communities with high human to dog ratios. School-based surveys partially overcame sampling constraints, however, were also costly to obtain reasonably precise estimates of coverage. Post-vaccination transects provided precise and timely estimates of community-level coverage that could be used to troubleshoot the performance of campaigns across large areas. However, transects typically overestimated coverage by around 10%, which therefore needs consideration when evaluating the impacts of campaigns. We discuss the advantages and disadvantages of these different methods and make recommendations for how vaccination campaigns can be better monitored and managed at different stages of rabies control and elimination programs.

Background Rabies is a notoriously underreported and neglected disease of low-income countries. This study aims to estimate the public health and economic burden of rabies circulating in domestic dog populations, globally and on a country-by-country basis, allowing an objective assessment of how much this preventable disease costs endemic countries. Methodology/Principal Findings We established relationships between rabies mortality and rabies prevention and control measures, which we incorporated into a model framework. We used data derived from extensive literature searches and questionnaires on disease incidence, control interventions and preventative measures within this framework to estimate the disease burden. The burden of rabies impacts on public health sector budgets, local communities and livestock economies, with the highest risk of rabies in the poorest regions of the world. This study estimates that globally canine rabies causes approximately 59,000 (95% Confidence Intervals: 25-159,000) human deaths, over 3.7 million (95% CIs: 1.6-10.4 million) disability-adjusted life years (DALYs) and 8.6 billion USD (95% CIs: 2.9-21.5 billion) economic losses annually. The largest component of the economic burden is due to premature death (55%), followed by direct costs of post-exposure prophylaxis (PEP, 20%) and lost income whilst seeking PEP (15.5%), with only limited costs to the veterinary sector due to dog vaccination (1.5%), and additional costs to communities from livestock losses (6%). Conclusions/Significance This study demonstrates that investment in dog vaccination, the single most effective way of reducing the disease burden, has been inadequate and that the availability and affordability of PEP needs improving. Collaborative investments by medical and veterinary sectors could dramatically reduce the current large, and unnecessary, burden of rabies on affected communities. Improved surveillance is needed to reduce uncertainty in burden estimates and to monitor the impacts of control efforts., Author Summary Rabies is a fatal viral disease largely transmitted to humans from bites by infected animals—predominantly from domestic dogs. The disease is entirely preventable through prompt administration of post-exposure prophylaxis (PEP) to bite victims and can be controlled through mass vaccination of domestic dogs. Yet, rabies is still very prevalent in developing countries, affecting populations with limited access to health care. The disease is also grossly underreported in these areas because most victims die at home. This leads to insufficient prioritization of rabies prevention in public health agendas. To address this lack of information on the impacts of rabies, in this study, we compiled available data to provide a robust estimate of the health and economic implications of dog rabies globally. The most important impacts included: loss of human lives (approximately 59,000 annually) and productivity due to premature death from rabies, and costs of obtaining PEP once an exposure has occurred. The greatest risk of developing rabies fell upon the poorest regions of the world, where domestic dog vaccination is not widely implemented and access to PEP is most limited. A greater focus on mass dog vaccination could eliminate the disease at source, reducing the need for costly PEP and preventing the large and unnecessary burden of mortality on at-risk communities.

Background Despite being entirely preventable, canine rabies still kills 55,000 people/year in developing countries. Information about local beliefs and practices can identify knowledge gaps that may affect prevention practices and lead to unnecessary deaths. Methodology/Principal Findings We investigated knowledge, attitudes and practices related to rabies and its prevention and control amongst a cross-section of households (n = 5,141) in urban and rural areas of central, southern and northern Tanzania. Over 17% of respondents owned domestic dogs (average of 2.3 dogs/household),>95% had heard about rabies, and>80% knew that rabies is transmitted through dog bites. People who (1) had greater education, (2) originated from areas with a history of rabies interventions, (3) had experienced exposure by a suspect rabid animal, (4) were male and (5) owned dogs were more likely to have greater knowledge about the disease. Around 80% of respondents would seek hospital treatment after a suspect bite, but only 5% were aware of the need for prompt wound cleansing after a bite. Although>65% of respondents knew of dog vaccination as a means to control rabies, only 51% vaccinated their dogs. Determinants of dog vaccination included (1) being a male-headed household, (2) presence of children, (3) low economic status, (4) residing in urban areas, (5) owning livestock, (6) originating from areas with rabies interventions and (7) having purchased a dog. The majority of dog-owning respondents were willing to contribute no more than US$0.31 towards veterinary services. Conclusions/Significance We identified important knowledge gaps related to, and factors influencing the prevention and control of rabies in Tanzania. Increasing knowledge regarding wound washing, seeking post-exposure prophylaxis and the need to vaccinate dogs are likely to result in more effective prevention of rabies; however, greater engagement of the veterinary and medical sectors is also needed to ensure the availability of preventative services., Author Summary Rabies remains a major public health problem in Africa and Asia, although means to control and prevent the disease are available through mass dog vaccination and provision of post-exposure prophylaxis to people exposed to bites by suspect rabid animals. Here we report the results of an extensive community survey on knowledge, attitudes and practices related to rabies control and prevention, covering rural and urban settings in central, northern and southern Tanzania. Our results showed that the majority of people across Tanzania had heard about rabies and knew that it is transmitted by dog bites, but most lacked comprehensive knowledge about key practices, such as the need for wound cleansing, which could prevent unnecessary deaths from the disease. In other circumstances, knowledge (for example, about the need to vaccinate dogs to control rabies) did not reflect good practice. In order to address the knowledge gaps identified by this study, there is a need for interventions aimed at increasing awareness, focusing on simple messages and targeting the community as a whole. This information could be channelled through media, community meetings and professionals including community leaders, health workers, teachers, livestock officers and clinicians.

Rabies is a fatal viral zoonotic infection caused by a Lyssavirus. Rabies exerts a major public health and economic burden; it is responsible for at least 55,000 deaths worldwide, predominantly in Africa and Asia. More than 90% of rabies deaths are caused by domestic dogs. Global expenditure on rabies prevention and control exceeds US$500 million per annum. Although human rabies is 100% preventable, through vaccination of animal reservoirs and post-exposure prophylaxis (PEP) of people exposed to bites, no effective large-scale control of rabies has been achieved in sub-Saharan Africa. Effective implementation of sustainable rabies control and prevention programs, involves full participation of individuals, veterinary and medical services. Veterinary services must control rabies transmission through mass dog vaccination campaigns because human deaths are caused by epidemics in domestic dogs, medical services must provide PEP to prevent disease in exposed individuals and exposed individuals must seek PEP and dog owners must take their dogs to be vaccinated. This thesis focuses on factors affecting individuals and medical services. This thesis examines challenges in the control and prevention of rabies in sub-Saharan Africa. Firstly, to address these challenges, we developed an analytical framework to portray the influence of individual and institutional factors within both the veterinary and medical services, in controlling and preventing rabies. The research carried out in chapters two and three investigate different aspects of this framework. Specifically in Chapter 2, we conducted a knowledge, attitude and practice (KAP) survey in seven districts covering southern, central and northern Tanzania. We used the collected data to investigate factors that influence knowledge of rabies and how knowledge of rabies influences attitudes and practice in control and prevention of rabies. Our findings show that knowledge about rabies in Tanzania is limited. However, we found an indication that those who were more knowledgeable of rabies claimed to practise better rabies control and prevention. In Chapter 3, we collected information using contact tracing and questionnaires to evaluate the burden of rabies and its impacts on local communities. The study demonstrated that rabies is a substantial economic concern to bite victims. A bite victim in Tanzania would be required to spend over US$70 to complete WHO recommended PEP schedules. The costs of PEP disproportionately affect bite victims from rural areas where PEP doses are often not available. Families reported spending family allowances, borrowing money and or selling crops or livestock to pay for PEP. Fewer than 10% of families paid for PEP from their salary compared to 15% of patients from urban areas. Otherwise, patients depended on external financial sources such as contributions from relatives or friends or decided not to seek PEP because of the high costs involved. High PEP costs also affected compliance with PEP schedules. The probability of obtaining the first dose of PEP was about 70%, declined slightly for the second and third doses but declined dramatically for the fourth and fifth doses. We also found that 15% of bite victims who did not receive any PEP went on to develop rabies. The costs of PEP were 2 times higher than costs previously reported from Africa. In Chapter 4 we discuss our overall results and conclude that interventions to control and prevent rabies require multi-sector commitment of all key stakeholders.