Cost-effectiveness of the national dog rabies prevention and control program in Mexico, 1990-2015.

BACKGROUND: Rabies is a viral zoonosis that imposes a substantial disease and economic burden in many developing countries. Dogs are the primary source of rabies transmission; eliminating dog rabies reduces the risk of exposure in humans significantly. Through mass annual dog rabies vaccination campaigns, the national program of rabies control in Mexico progressively reduced rabies cases in dogs and humans since 1990. In 2019, the World Health Organization validated Mexico for eliminating rabies as a public health problem. Using a governmental perspective, we retrospectively assessed the economic costs, effectiveness, and cost-effectiveness of the national program of rabies control in Mexico, 1990-2015. METHODOLOGY: Combining various data sources, including administrative records, national statistics, and scientific literature, we retrospectively compared the current scenario of annual dog vaccination campaigns and post-exposure prophylaxis (PEP) with a counterfactual scenario without an annual dog vaccination campaign but including PEP. The counterfactual scenario was estimated using a mathematical model of dog rabies transmission (RabiesEcon). We performed a thorough sensitivity analysis of the main results. PRINCIPAL FINDINGS: Results suggest that in 1990 through 2015, the national dog rabies vaccination program in Mexico prevented about 13,000 human rabies deaths, at an incremental cost (MXN 2015) of $4,700 million (USD 300 million). We estimated an average cost of $360,000 (USD 23,000) per human rabies death averted, $6,500 (USD 410) per additional year-of-life, and $3,000 (USD 190) per dog rabies death averted. Results were robust to several counterfactual scenarios, including high and low rabies transmission scenarios and various assumptions about potential costs without mass dog rabies vaccination campaigns. CONCLUSIONS: Annual dog rabies vaccination campaigns have eliminated the transmission of dog-to-dog rabies and dog-mediated human rabies deaths in Mexico. According to World Health Organization standards, our results show that the national program of rabies control in Mexico has been highly cost-effective.

Public Veterinary Medicine: Public Health: Rabies surveillance in the United States during 2018.

OBJECTIVE: To describe rabies and rabies-related events occurring during 2018 in the United States. ANIMALS: All animals submitted for laboratory diagnosis of rabies in the United States during 2018. PROCEDURES: State and territorial public health departments provided data on animals submitted for rabies testing in 2018. Data were analyzed temporally and geographically to assess trends in domestic animal and wildlife rabies cases. RESULTS: During 2018, 54 jurisdictions reported 4,951 rabid animals to the CDC, representing an 11.2% increase from the 4,454 rabid animals reported in 2017. Texas (n = 695 [14.0%]), Virginia (382 [7.7%]), Pennsylvania (356 [7.2%]), North Carolina (332 [6.7%]), Colorado (328 [6.6%]), and New York (320 [6.5%]) together accounted for almost half of all rabid animals reported in 2018. Of the total reported rabies cases, 4,589 (92.7%) involved wildlife, with bats (n = 1,635 [33.0%]), raccoons (1,499 [30.3%]), skunks (1,004 [20.3%]), and foxes (357 [7.2%]) being the major species. Rabid cats (n = 241 [4.9%]) and dogs (63 [1.3%]) accounted for > 80% of rabid domestic animals reported in 2018. There was a 4.6% increase in the number of samples submitted for testing in 2018, compared with the number submitted in 2017. Three human rabies deaths were reported in 2018, compared with 2 in 2017. CONCLUSIONS AND CLINICAL RELEVANCE: The overall number of animal rabies cases increased from 2017 to 2018. Laboratory diagnosis of rabies in animals is critical to ensure that human rabies postexposure prophylaxis is administered judiciously.

Successful strategies implemented towards the elimination of canine rabies in the Western Hemisphere.

Almost all cases of human rabies result from dog bites, making the elimination of canine rabies a global priority. During recent decades, many countries in the Western Hemisphere have carried out large-scale dog vaccination campaigns, controlled their free-ranging dog populations and enforced legislation for responsible pet ownership. This article reviews progress in eliminating canine rabies from the Western Hemisphere. After briefly summarizing the history of control efforts and describing the approaches listed above, we note that programs in some countries have been hindered by societal attitudes and severe economic disparities, which underlines the need to discuss measures that will be required to complete the elimination of canine rabies throughout the region. We also note that there is a constant threat for dog-maintained epizootics to re-occur, so as long as dog-maintained rabies "hot spots" are still present, free-roaming dog populations remain large, herd immunity becomes low and dog-derived rabies lyssavirus (RABLV) variants continue to circulate in close proximity to rabies-naïve dog populations. The elimination of dog-maintained rabies will be only feasible if both dog-maintained and dog-derived RABLV lineages and variants are permanently eliminated. This may be possible by keeping dog herd immunity above 70% at all times, fostering sustained laboratory-based surveillance through reliable rabies diagnosis and RABLV genetic typing in dogs, domestic animals and wildlife, as well as continuing to educate the population on the risk of rabies transmission, prevention and responsible pet ownership. Complete elimination of canine rabies requires permanent funding, with governments and people committed to make it a reality. An accompanying article reviews the history and epidemiology of canine rabies in the Western Hemisphere, beginning with its introduction during the period of European colonization, and discusses how spillovers of viruses between dogs and various wild carnivores will affect future eradication efforts (Velasco-Villa et al., 2017).

Concomitant administration of GonaCon™ and rabies vaccine in female dogs (Canis familiaris) in Mexico.

Mexico serves as a global model for advances in rabies prevention and control in dogs. The Mexican Ministry of Health (MMH) annual application of approximately 16 million doses of parenteral rabies vaccine has resulted in significant reductions in canine rabies during the past 20 years. One collateral parameter of rabies programs is dog population management. Enhanced public awareness is critical to reinforce responsible pet ownership. Surgical spaying and neutering remain important to prevent reproduction, but are impractical for achieving dog population management goals. GonaCon™, an anti-gonadotropin releasing hormone (GnRH) vaccine, was initially tested in captive female dogs on the Navajo Nation, 2008. The MMH led this international collaborative study on an improved formulation of GonaCon™ in captive dogs with local representatives in Hidalgo, Mexico in 2011. This study contained 20 bitches assigned to Group A (6 control), Group B (7 GonaCon™), and Group C (7 GonaCon™ and rabies vaccine). Vaccines were delivered IM. Animals were placed under observation and evaluated during the 61-day trial. Clinically, all dogs behaved normally. No limping or prostration was observed, in spite of minor muscle atrophy post-mortem in the left hind leg of dogs that received GonaCon™. Two dogs that began the study pregnant give birth to healthy pups. Dogs that received a GonaCon™ injection had macro and microscopic lesions consistent with prior findings, but the adverse injection effects were less frequent and lower in intensity. Both vaccines were immunogenic based on significant increases in rabies virus neutralizing antibodies and anti-GnRH antibodies in treatment Groups B and C. Simultaneous administration of GonaCon™ and rabies vaccine in Group C did not affect immunogenicity. Progesterone was suppressed significantly in comparison to controls. Future studies that monitor fertility through multiple breeding cycles represent a research need to determine the value of integrating this vaccine into dog rabies management.