Rabies in the Americas: 1998-2014

Abstract

Through national efforts and regional cooperation under the umbrella of the Regional Program for the Elimination of Rabies, dog and human rabies have decreased significantly in Latin America and Caribbean (LAC) countries over the last three decades. To achieve this decline, LAC countries had to develop national plans, and consolidate capabilities such as regular mass dog vaccination, opportune post-exposure prophylaxis and sensitive surveillance. This paper presents longitudinal data for 21 LAC countries on dog vaccination, PEP and rabies surveillance collected from the biannual regional meeting for rabies directors from 1998-2014 and from the Regional Epidemiologic Surveillance System for Rabies (SIRVERA). Differences in human and dog rabies incidence rates and dog vaccination rates were shown between low, middle and high-income countries. At the peak, over 50 million dogs were vaccinated annually in national campaigns in the countries represented. The reported number of animal exposures remained fairly stable during the study period with an incidence rate ranging from 123 to 191 reported exposures per 100,000 people. On average, over 2 million doses of human vaccine were applied annually. In the most recent survey, only 37% of countries reported that they had sufficient financial resources to meet the program objectives. The data show a sufficient and sustained effort of the LAC countries in the area of dog vaccination and provide understanding of the baseline effort required to reduce dog-mediated rabies incidence.

Fig 1. Human and dog rabies cases in LAC countries reported to SIRVERA.

(A) Human case counts since the beginning of regional elimination program, period 1983–2014. Data collection on aggressor species began in 1993 (vertical dashed line). Human cases from all aggressor species are represented with circles from 1983 and dog-mediated cases with triangles from 1993 onward. (B) Dog-mediated human case incidence per 100,000 population by income category (WB, 2014) at the tail end of the epidemic with Loess smoother, period 1998–2014. (C) Dog case counts since the beginning of regional elimination program, period 1983–2014. (D) Dog rabies incidence per 100,000 dogs by income category at the tail end of the epidemic, period 1998–2014, using reported dog population.

Fig 2. Dog vaccination in Latin America.

(A) Number of Dogs Vaccinated in government campaigns per year in the region in the 21 reporting countries. Original Data is in black, imputed data is in grey. The incidence of dog rabies (per million dogs) in the region is overlaid in black for comparison (B) Box plots showing vaccination coverage rates for countries categorized by income category.

Fig 3. Animal exposures and post-exposure-prophylaxis (PEP).

(A) Number of animal exposures and number of human rabies vaccines applied by year, period 1998–2014; (B) Ratio PEP doses to number of exposures; (C) Incidence of exposures per 100,000 population.

Fig 4. Indicators of national program capability in 2013–2014.

Percentage of country respondents (n = 19) in 2013–2014 with national rabies control programs and basic indicators for control programs.