Fifty Years of the National Rabies Control Program in Brazil under the One Health Perspective.

In 1973, the National Rabies Program was created in Brazil through an agreement between the Ministry of Health and Agriculture. Since its beginning, it developed integrated action through access to free post-exposure prophylaxis (PEP) for people at risk, dog vaccination campaigns, a joint surveillance system, and awareness. This study aims to describe human rabies in Brazil under the One Health perspective in recent decades, including achievements in the control of dog-mediated cases and challenges in human cases transmitted by wild animals. This paper also explores possible drivers of human rabies in the Northeast Region with half of the cases. The first part of this study was descriptive, presenting data and examples by periods. Statistical analysis was performed in the last period (2010-2022) to explore possible drivers. Dog-mediated human cases decreased from 147 to 0, and dog cases decreased from 4500 to 7. A major challenge is now human cases transmitted by wild animals (bats, non-human primates, and wild canids). Most current human cases occur in municipalities with a tropical and subtropical moist broadleaf forest biome and a Gini index higher than 0.5. In the multivariable analysis, an association with temperature was estimated (OR = 1.739; CI95% = 1.181-2.744), and primary healthcare coverage (OR = 0.947; CI95% = 0.915-0.987) was identified as a protector. It is possible to significantly reduce the number of dog-mediated human rabies cases through the efforts presented. However, Brazil has wildlife variants of the rabies virus circulating. The association of human cases with higher temperatures in the Northeast is a concern with climate change. To reduce human cases transmitted by wild animals, it is important to continue distributing free PEP, especially in remote at-risk areas in the Amazon Region, and to increase awareness.

Leptospirosis Risk among Occupational Groups in Brazil, 2010-2015.

Leptospirosis is a zoonotic disease that is primarily transmitted through close contact with contaminated environments or infected animals. Brazil has the highest number of reported cases of leptospirosis in the Americas (approximately 4,000 annual cases). The purpose of this study is to identify the occupational groups with a higher risk of leptospirosis in Brazil from 2010 through 2015 among suspected cases reported to the national surveillance system. Confirmed and unconfirmed cases of leptospirosis with laboratory diagnosis, 20,193 and 59,034 respectively, were classified into 12 occupational groups. Confirmed cases were predominantly male (79.4%), between 25 and 59 years of age (68.3%), white (53.4%), illiterate or with incomplete primary education (51.1%), and participating in agricultural work (19.9%). After controlling for age, sex, race, and area of residency, the multivariate analysis identified that between confirmed and unconfirmed cases of leptospirosis reported to the Brazilian national surveillance system, five occupational groups are at higher risk for leptospirosis: garbage and recycling collectors (odds ratio [OR] = 4.10; 95% CI = 3.36-4.99); agricultural, forestry, and fishery workers (OR = 1.65; 95% CI = 1.49-1.84); prisoners (OR = 1.56; 95% CI = 1.04-2.35); building workers (OR = 1.36; 95% CI = 1.22-1.51); cleaners and mining workers (OR = 1.25; 95% CI = 1.07-1.45). This is the first nationwide study to examine leptospirosis risk by occupational group in Brazil using national surveillance data. Our results suggest that among suspected cases there was an increased risk among occupational groups with low income and low educational levels.

Presence and Multi-Species Spatial Distribution of Oropouche Virus in Brazil within the One Health Framework.

Oropouche virus (OROV) is an emerging vector-borne arbovirus with high epidemic potential, causing illness in more than 500,000 people. Primarily contracted through its midge and mosquito vectors, OROV remains prevalent in its wild, non-human primate and sloth reservoir hosts as well. This virus is spreading across Latin America; however, the majority of cases occur in Brazil. The aim of this research is to document OROV's presence in Brazil using the One Health approach and geospatial techniques. A scoping review of the literature (2000 to 2021) was conducted to collect reports of this disease in humans and animal species. Data were then geocoded by first and second subnational levels and species to map OROV's spread. In total, 14 of 27 states reported OROV presence across 67 municipalities (second subnational level). However, most of the cases were in the northern region, within the tropical and subtropical moist broadleaf forests biome. OROV was identified in humans, four vector species, four genera of non-human primates, one sloth species, and others. Utilizing One Health was important to understand the distribution of OROV across several species and to suggest possible environmental, socioeconomic, and demographic drivers of the virus's presence. As deforestation, climate change, and migration rates increase, further study into the spillover potential of this disease is needed.

Snakebites in Rural Areas of Brazil by Race: Indigenous the Most Exposed Group.

Animal stings are environmental hazards that threaten millions annually and cause a significant socioeconomic impact. Snakebite envenoming affects 2.7 million people globally every year, mostly the poorest and rural communities, with approximately 27,000 annual cases in Brazil. This study's objective is to identify the most exposed racial group for snakebites in rural areas of Brazil and analyze possible differences in the outcome of an accident. A retrospective epidemiological study was conducted using a database of rural snakebite cases from Brazil's Ministry of Health (2017). Descriptive analysis and a regression model were performed to examine the association of bad outcomes after a snakebite with several covariables. While mixed-race individuals presented the highest number of cases (61.79%), indigenous and white populations were the racial groups with the highest and lowest exposure rates (194.3 and 34.1 per 100,000 population, respectively). The fatality rate was 3.5 times higher in the indigenous population compared to the white population. In the multivariable model, the number of hours between the accident and health care received and the case classification suggested an association with a bad outcome. Snakebite is prominent in Brazil, particularly among indigenous groups. Antivenom is available in the Brazilian Health System; however, efforts need to be made for decentralization.

Epidemiology of human leptospirosis in urban and rural areas of Brazil, 2000-2015.

BACKGROUND: Leptospirosis is one of the most widespread zoonosis in the world and Brazil has the highest number of cases in Latin America. Transmission occurs mainly through exposure to water and soil contaminated by the urine of infected animals. The goals of this study are to describe the geographic distribution, demographic characteristics and exposure factors of urban and rural cases of leptospirosis, and identify spatial clusters in urban and rural areas of Brazil. METHODS/RESULTS: A retrospective epidemiological study was carried out using 16 years (2000-2015) of surveillance data from the Brazilian Ministry of Health. Cases were described by age, sex and race, and exposure factors were characterized in urban and rural areas. A spatial autocorrelation analysis was conducted using local Moran's I to identify urban and rural clusters of disease. On average 3,810 leptospirosis cases were reported annually with higher numbers in urban areas. National urban and rural incidence rates were the same (1.9 cases/100,000 population), however, regional differences were observed. Urban incidence rates were higher in the North and Northeast regions, while rural incidence rates were higher in the Southeast and South. The main exposure factor reported in urban and rural areas was exposure to places with signs of rodents, followed by flood in urban areas and agriculture and animal farming in rural areas. Clusters of leptospirosis were identified in densely populated urban areas of the North, Southeast and South regions, while rural clusters were concentrated in of the Southern region with large agriculture and animal farming practices. CONCLUSIONS: This study highlights that leptospirosis is an important public health problem in both urban and rural areas of Brazil. The results provide decision-makers with detailed information about where disease incidence is high and can be used in the development of prevention and control strategies for priority areas and risk groups.

An exploration of the protective effect of rodent species richness on the geographical expansion of Lassa fever in West Africa.

BACKGROUND: Lassa fever (LF) is one of the most devastating rodent-borne diseases in West Africa, causing thousands of deaths annually. The geographical expansion of LF is also a concern; cases were recently identified in Ghana and Benin. Previous ecological studies have suggested that high natural-host biodiversity reduces the likelihood of spillover transmission of rodent-borne diseases, by suppressing the activities of reservoir species. However, the association of biodiversity with the geographical expansion of LF has not been the subject of epidemiological studies. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a spatial analysis based on sociodemographic, geographical, and ecological data, and found that higher rodent species richness was significantly associated with a lower risk of LF emergence in West Africa from 2008 to 2017 (Odds Ratio = 0.852, 95% Credible Interval = 0.745-0.971). CONCLUSIONS/SIGNIFICANCE: The results reinforce the importance of the 'One Health' approach by demonstrating that a high level of biodiversity could benefit human health.

Overview of snakebite in Brazil: Possible drivers and a tool for risk mapping.

Snakebite envenoming affects close to 2.7 million people globally every year. In Brazil, snakebites are reported to the Ministry of Health surveillance system and cases receive antivenom free of charge. There is an urgent need to identify higher risk areas for antivenom distribution, and to develop prevention activities. The objective of this study is to provide an overview of the epidemiological situation of snakebite envenoming in Brazil and explore possible drivers; as well as to create a flowchart tool to support decision-makers identify higher risk areas. An ecological-type study was carried out using data by municipality (2013-2017). Study parts: 1) Create a geocoded database and perform a descriptive and cluster analysis; 2) Statistical analysis to measure the association of snakebite and possible environmental and socioeconomic drivers; 3) Develop a flowchart to support decision-makers and the application of this tool in one state (Rio Grande do Sul) as an example. An average of 27,120 snakebite cases per year were reported at the country level. Clusters of municipalities with high numbers of snakebites are mostly found in the Amazon Legal Region. The negative binomial regression model showed association with the snakebite case count: the type of major habitat, tropical or non-tropical; temperature; percentage of urbanization; precipitation; elevation; GDP per capita; a weaker relation with forest loss; and with venomous snake richness. The state where the instrument was applied reported 4,227 snakebites in the period. Most municipalities were considered as medium risk and 56/496 as high risk according to the tool created. Snakebite cases are distributed across the entire country with the highest concentration in the Legal Amazon Region. This creates a complex situation both for better understanding of the association of environmental and socioeconomic factors with snakebites and for the distribution and maintenance of antivenom to remote areas. Research into types of antivenom with a longer shelf life without the need for refrigeration is needed.

Association between predator species richness and human hantavirus infection emergence in Brazil.

Hantavirus infection is a rodent-borne disease (RBD) transmitted by urine or feces (as the natural reservoirs) with an annual estimated worldwide incidence of ~150,000 cases. Previous ecological studies suggested that higher species richness of rodents could decrease the risk of RBDs in humans, because the regulatory pressure of predators could reduce contact among rodents, and between humans and rodents. Using surveillance data, we investigated the association of predator species richness with hantavirus infection emergence in 5562 Brazilian inland municipalities between 2007 and 2017. Multivariable logistic regression models were used for the analyses. Diurnal and non-diurnal predator species were independent explanatory variables in the models. Rodent species richness and demographic, socioeconomic, and environmental factors were used as covariates. During the study period, 1084 cases were reported in 429 municipalities. The results showed a reverse-U-shaped association between diurnal predator species richness and hantavirus infection emergence (odds ratio [OR] 0.463, 0.688, and 0.553 for the first [lowest], third, and fourth [highest] quartiles, respectively, using the second quartile as a reference), while higher non-diurnal predator species richness tended to be associated with higher emergence risk (OR 0.134, 1.065, and 2.708 for the first, third, and fourth quartiles, respectively). The difference in these associations illustrates the complexity of the effects of predator species richness on human RBDs, which require further investigation in follow-up studies. The results showed a close link between environmental factors and public health, emphasizing that the One Health concept should be employed to understand the dynamics of RBDs.

Protective effect of predator species richness on human hantavirus infection incidence.

Are predators of rodents beneficial for public health? This question focuses on whether predators regulate the spillover transmission of rodent-borne diseases. No clear answer has emerged because of the complex linkages across multiple trophic levels and the lack of accessible data. Although previous empirical findings have suggested ecological mechanisms, such as resource partitioning, which implies protective effects from predator species richness, epidemiological evidence is needed to bolster these arguments. Thus, we investigated the association between predator species richness and incidence of rodent-borne haemorrhagic fever with renal syndrome in the human population using district-level longitudinal data of 13 years for South Korea. With the exception of districts with low species richness, we found a significant negative association between the incidence of haemorrhagic fever with renal syndrome and the species richness of both avian and mammalian predators; the trends for both predator types were similar. Thus, biodiversity conservation may benefit public health.

A systematic literature review of leptospirosis outbreaks worldwide, 1970-2012.

OBJECTIVE: This review describes the geographic and temporal distribution of, detection methods for, and other epidemiological features of published leptospirosis outbreaks, with the aim of informing efforts to standardize outbreak-reporting practices. METHODS: We conducted a systematic review of leptospirosis outbreaks reported in the scientific literature and ProMED during 1970-2012. Predefined criteria were used to identify and classify outbreaks and a standard form was used to extract information. RESULTS: During 1970-2012, we identified 318 outbreaks (average: 7 outbreaks/year; range: 1-19). Most outbreaks were reported in the Latin America and the Caribbean region (36%), followed by Southern Asia (13%), and North America (11%). Most outbreaks were located in tropical and subtropical ecoregions (55%). Quality classification showed that there was clear description of laboratory-confirmed cases in 40% of outbreaks. Among those, the average outbreak size was 82 cases overall (range: 2-2 259) but reached 253 cases in tropical/subtropical ecoregions. Common risk factors included outdoor work activities (25%), exposure to floodwaters (23%), and recreational exposure to water (22%). Epidemiologic investigation was conducted in 80% of outbreaks, mainly as case interviews. Case fatality was 5% overall (range: 0%-60%). CONCLUSIONS: Outbreak reporting increased over the study period with outbreaks covering tropical and non-tropical regions. Outbreaks varied by size, setting, and risk factors; however, data reviewed often had limited information regarding diagnosis and epidemiology. Guidelines are recommended to develop standardized procedures for diagnostic and epidemiological investigations during an outbreak and for reporting.

OBJETIVO: Describir la distribución geográfica y temporal, los métodos de detección y otras características epidemiológicas de los brotes de leptospirosis publicados con el fin de fundamentar los esfuerzos tendientes a estandarizar las prácticas empleadas en la notificación de brotes. MÉTODOS: Se llevó a cabo una revisión sistemática de los brotes de leptospirosis notificados en la bibliografía científica y en ProMED entre 1970 y 2012. Se utilizaron criterios predefinidos para identificar y clasificar los brotes y se empleó un formulario estándar para extraer la información. RESULTADOS: Entre 1970 y 2012 se identificaron 318 brotes (promedio: 7 brotes/año; rango: 1-19), la mayoría de ellos en América Latina y el Caribe (36%), región seguida por Asia meridional (13%) y América del Norte (11%). La mayoría de los brotes se localizaron en ecorregiones tropicales y subtropicales (55%). La clasificación cualitativa reveló que en el 40% de los brotes había una clara descripción de los casos confirmados por laboratorio. Entre ellos, el tamaño promedio del brote fue de 82 casos (rango: 2-2259 casos) pero alcanzó los 253 casos en ecorregiones tropicales o subtropicales. Entre los factores de riesgo frecuentes figuraban las actividades laborales al aire libre (25%), la exposición a agua proveniente de inundaciones (23%) y la exposición a agua con fines recreativos (22%). En el 80% de los brotes se realizaron investigaciones epidemiológicas, principalmente entrevistas de casos. La mortalidad específica de los casos fue del 5% (rango: 0%-60%). CONCLUSIONES: La notificación de brotes aumentó durante el período de estudio, y los brotes abarcaron regiones tropicales y no tropicales. Los brotes fueron diferentes en cuanto a su tamaño, el entorno y los factores de riesgo; sin embargo, los datos examinados con frecuencia incluían una información limitada respecto del diagnóstico y la epidemiología. Se recomiendan directrices para elaborar procedimientos estandarizados para las investigaciones diagnósticas y epidemiológicas durante un brote y para su notificación.

A systematic literature review of leptospirosis outbreaks worldwide, 1970-2012 / Revisión sistemática de los brotes de leptospirosis en el mundo, 1970-2012

ABSTRACT Objective. This review describes the geographic and temporal distribution of, detection methods for, and other epidemiological features of published leptospirosis outbreaks, with the aim of informing efforts to standardize outbreak-reporting practices. Methods. We conducted a systematic review of leptospirosis outbreaks reported in the scientific literature and ProMED during 1970-2012. Predefined criteria were used to identify and classify outbreaks and a standard form was used to extract information. Results. During 1970-2012, we identified 318 outbreaks (average: 7 outbreaks/year; range: 1-19). Most outbreaks were reported in the Latin America and the Caribbean region (36%), followed by Southern Asia (13%), and North America (11%). Most outbreaks were located in tropical and subtropical ecoregions (55%). Quality classification showed that there was clear description of laboratory-confirmed cases in 40% of outbreaks. Among those, the average outbreak size was 82 cases overall (range: 2-2 259) but reached 253 cases in tropical/subtropical ecoregions. Common risk factors included outdoor work activities (25%), exposure to floodwaters (23%), and recreational exposure to water (22%). Epidemiologic investigation was conducted in 80% of outbreaks, mainly as case interviews. Case fatality was 5% overall (range: 0%-60%). Conclusions. Outbreak reporting increased over the study period with outbreaks covering tropical and non-tropical regions. Outbreaks varied by size, setting, and risk factors; however, data reviewed often had limited information regarding diagnosis and epidemiology. Guidelines are recommended to develop standardized procedures for diagnostic and epidemiological investigations during an outbreak and for reporting.(AU)

RESUMEN Objetivo. Describir la distribución geográfica y temporal, los métodos de detección y otras características epidemiológicas de los brotes de leptospirosis publicados con el fin de fundamentar los esfuerzos tendientes a estandarizar las prácticas empleadas en la notificación de brotes. Métodos. Se llevó a cabo una revisión sistemática de los brotes de leptospirosis notificados en la bibliografía científica y en ProMED entre 1970 y 2012. Se utilizaron criterios predefinidos para identificar y clasificar los brotes y se empleó un formulario estándar para extraer la información. Resultados. Entre 1970 y 2012 se identificaron 318 brotes (promedio: 7 brotes/año; rango: 1-19), la mayoría de ellos en América Latina y el Caribe (36%), región seguida por Asia meridional (13%) y América del Norte (11%). La mayoría de los brotes se localizaron en ecorregiones tropicales y subtropicales (55%). La clasificación cualitativa reveló que en el 40% de los brotes había una clara descripción de los casos confirmados por laboratorio. Entre ellos, el tamaño promedio del brote fue de 82 casos (rango: 2-2259 casos) pero alcanzó los 253 casos en ecorregiones tropicales o subtropicales. Entre los factores de riesgo frecuentes figuraban las actividades laborales al aire libre (25%), la exposición a agua proveniente de inundaciones (23%) y la exposición a agua con fines recreativos (22%). En el 80% de los brotes se realizaron investigaciones epidemiológicas, principalmente entrevistas de casos. La mortalidad específica de los casos fue del 5% (rango: 0%-60%). Conclusiones. La notificación de brotes aumentó durante el período de estudio, y los brotes abarcaron regiones tropicales y no tropicales. Los brotes fueron diferentes en cuanto a su tamaño, el entorno y los factores de riesgo; sin embargo, los datos examinados con frecuencia incluían una información limitada respecto del diagnóstico y la epidemiología. Se recomiendan directrices para elaborar procedimientos estandarizados para las investigaciones diagnósticas y epidemiológicas durante un brote y para su notificación.(AU)

A One Health Approach to Investigating Leptospira Serogroups and Their Spatial Distributions among Humans and Animals in Rio Grande do Sul, Brazil, 2013⁻2015.

Leptospirosis is an endemic zoonotic disease in Brazil and is widespread throughout rural populations in the state of Rio Grande do Sul. This study aimed to identify presumptive infecting Leptospira serogroups in human and animal cases and describe their occurrences within the ecoregions of the state by animal species. Data for human and animal leptospirosis cases were gathered from the government's passive surveillance systems and presumptive infecting serogroups were identified based on a two-fold titer difference in serogroups in the microscopic agglutination test (MAT) panel. A total of 22 different serogroups were reported across both human and animal cases. Serogroup Icterohaemorrhagiae was the most common among humans, while serogroup Sejroe predominated among animal cases, particularly bovines. Each ecoregion had a large distribution of cases, with 51% of the human cases in the Parana⁻Paraiba ecoregion, and 81% of the animal cases in the Savannah ecoregion. Identifying and mapping the serogroups circulating using the One Health approach is the first step for further understanding the distribution of the disease in the state. This study has the potential to aid in guiding public health and agricultural practices, furthering the need for a human vaccine in high-risk populations to complement control and prevention efforts.

A road map for leptospirosis research and health policies based on country needs in Latin America.

This report summarizes the presentations, discussions and the recommendations coming from the Oswaldo Cruz Institute/FIOCRUZ International Workshop for Leptospirosis Research Based on Country Needs and the 5th Global Leptospirosis Environmental Action Network meeting, which was held in the city of Rio de Janeiro, Brazil, 10-12 November 2015. The event focused on health policy and worked to develop a road map as a consensus document to help guide decision-making by policymakers, funding bodies, and health care professionals. The direction that leptospirosis research should take in the coming years was emphasized, taking into account the needs of countries of Latin America, as well as experiences from other world regions, as provided by international experts. The operational concepts of "One Health" and translational research underlaid the discussions and the resulting recommendations. Despite the wide geographic distribution of leptospirosis and its impact in terms of incidence, morbidity, and mortality, leptospirosis is not yet considered a "tool-ready" disease for global initiatives. Surveillance programs need new tools and strategies for early detection, prevention, and follow-up. The major recommendations developed at the Rio meeting cover both health policy and research. The health policy recommendations should be taken into account by decisionmakers, government officials, and the Pan American Health Organization. The priorities for research, technological development, and innovation should be considered by research institutions, universities, and stakeholders.

Geographic patterns and environmental factors associated with human yellow fever presence in the Americas.

BACKGROUND: In the Americas, yellow fever virus transmission is a latent threat due to the proximity between urban and wild environments. Although yellow fever has nearly vanished from North and Central America, there are still 13 countries in the Americas considered endemic by the World Health Organization. Human cases usually occur as a result of the exposure to sylvatic yellow fever in tropical forested environments; but urban outbreaks reported during the last decade demonstrate that the risk in this environment still exists. The objective of this study was to identify spatial patterns and the relationship between key geographic and environmental factors with the distribution of yellow fever human cases in the Americas. METHODOLOGY/PRINCIPAL FINDINGS: An ecological study was carried out to analyze yellow fever human cases reported to the Pan American Health Organization from 2000 to 2014, aggregated by second administrative level subdivisions (counties). Presence of yellow fever by county was used as the outcome variable and eight geo-environmental factors were used as independent variables. Spatial analysis was performed to identify and examine natural settings per county. Subsequently, a multivariable logistic regression model was built. During the study period, 1,164 cases were reported in eight out of the 13 endemic countries. Nearly 83.8% of these cases were concentrated in three countries: Peru (37.4%), Brazil (28.1%) and Colombia (18.4%); and distributed in 57 states/provinces, specifically in 286 counties (3.4% of total counties). Yellow fever presence was significantly associated with altitude, rain, diversity of non-human primate hosts and temperature. A positive spatial autocorrelation revealed a clustered geographic pattern in 138/286 yellow fever positive counties (48.3%). CONCLUSIONS/SIGNIFICANCE: A clustered geographic pattern of yellow fever was identified mostly along the Andes eastern foothills. This risk map could support health policies in endemic countries. Geo-environmental factors associated with presence of yellow fever could help predict and adjust the limits of other risk areas of epidemiological concern.

The Use of Chemoprophylaxis after Floods to Reduce the Occurrence and Impact of Leptospirosis Outbreaks.

Record-breaking and devastating rainfall events have occurred in the past decade. Rain and floods are considered the main risk factors for leptospirosis and several outbreaks have been reported following extreme weather events. In such situations, one possible intervention to prevent leptospirosis cases in high-risk groups is the use of chemoprophylaxis. However, not enough evidence of its effect is available. The objectives of this study were to review the literature on the current practices of chemoprophylaxis for leptospirosis and to explore, using a mathematical model, how various chemoprophylaxis scenarios may affect the progression of a leptospirosis outbreak. Twenty-six peer-reviewed publications were selected (10 quantitative studies, two systematic reviews and 14 articles of other types). Oral doxycycline was the most used antibiotic for chemoprophylaxis of leptospirosis. Post-exposure prophylaxis was assessed in four studies following a natural disaster. Although evidence of the effectiveness of post-exposure prophylaxis is inconsistent, the direction of association supported a protective effect for morbidity and mortality. The theoretical model showed how the assumed benefit of chemoprophylaxis was influenced by the time and rate of administration. Future models should consider the heterogeneity of affected communities, improved estimates of the effect of chemoprophylaxis on leptospirosis infection and disease, as well as potential detrimental impacts. Additional research is critical to provide clear evidence-based recommendations for leptospirosis control during an outbreak. The results of this study suggest that chemoprophylaxis may provide some protection in reducing the number of leptospirosis cases after a high-risk exposure; however, the effective benefit may depend on a variety of factors such as the timing and coverage of prophylaxis. The information summarized can be used to support decision-making during a high-risk event.

Leptospirosis in Latin America: exploring the first set of regional data.

OBJECTIVES: To demonstrate the importance of country surveillance systems for leptospirosis and their use for preliminary epidemiological analysis, as well as to generate research questions for future, morecomprehensive studies on the disease. METHODS: In 2015, for the first time, the Pan American Health Organization (PAHO) included human cases of leptospirosis in its Regional Core Health Data Initiative, an open-access database that collects annual health indicators from the countries and territories of the Americas. This new information was used to analyze leptospirosis cases by country and sex and to calculate cumulative incidence rates. Maps were used to help present the results. To supplement that general review of leptospirosis in the Americas, more detailed descriptions of the epidemiological situation and the surveillance programs of four selected countries (Brazil, Colombia, Cuba, and Honduras) were provided. RESULTS: In this first year of PAHO requesting leptospirosis data, of the 49 countries and territories in the Americas, 38 of them (77.6%) reported information. Among those 38, 28 of them (73.7%) reported the presence of human cases; the majority of instances of zero cases were in Caribbean territories. From those 28, a total of 10 702 human cases were recorded. The largest numbers of cases in Latin America were in Brazil (40.2%), Peru (23.6%), Colombia (8.8%), and Ecuador (7.2%). The cumulative incidence rate for Latin America was estimated to be 2.0 per 100 000 population. On average, 65.1% of cases were males. CONCLUSIONS: This study demonstrates that many countries in Latin America are making efforts to establish strong surveillance systems and programs for leptospirosis. The study also shows the importance of having leptospirosis surveillance systems as well as how the information generated can be used for evidence-based decision-making on leptospirosis.