Wildlife as Food and Medicine in Brazil: A Neglected Zoonotic Risk?

The practice of consuming wild fauna in Brazil is both culturally and socioeconomically questionable. Wild animals and their byproducts are sought for nutritional, medicinal, and/or supernatural reasons, with some taxa (e.g., songbirds) being kept as pets. This practice is concentrated in traditional and rural communities, as well as the rural exodus populations in large urban centers, maintained both by cultural preferences and for their role in food safety in part of the rural exodus community. A total of 564 taxa are known to be sold in wet markets in Brazil, with birds, fish, and mammals being the most commonly listed. There is great zoonotic outbreak potential in this consumption chain given the diversity of species involved (with several listed being known reservoirs of zoonotic pathogens), invasion of wild environments for hunting, unsanitary processing of carcasses, and consumption of most/all biotopes of the animal, as well as the creation of favorable conditions to cross-species pathogen transmission. Given its socioeconomic situation and the global trends in disease emergence, there is a risk of the future emergence of a Public Health Emergency of International Concern in Brazil through wildlife consumption.

Prevalence of human leptospirosis in the Americas: a systematic review and meta-analysis.

Objective: To describe the prevalence of leptospirosis in the Americas. Methods: A systematic review and meta-analysis, in the period 1930 to 2017, performed on a search of six platforms: PubMed, Web of Science, Scopus, Lilacs, Embase, and Cochrane. Results: The search found 77 publications of which 53 (68%) were from the period 2000-2017. Of the 77, 62 studies were included in the analysis, from North America (11, 17%), Central America (9, 14%), and South America (42, 67%), and 22 studies were from urban areas. Leptospirosis prevalence in the 62 studies analyzed corresponded to 28% (95% CI [23, 32]). Countries with higher prevalence were United States of America (41%), Colombia (29%), and Brazil (21%). The most frequent serovars found were Icterohaemorrhagiae (43 of 77 publications, 55%), Canicola (35, 45%), Pomona (28, 36%), and Grippotyphosa (26, 33%). Conclusions: There is variability of Leptospira species and serovars with heterogenous distribution throughout the Americas, with high prevalence in some countries, highlighting the need for action to control the disease.

Factors associated with differential seropositivity to Leptospira interrogans and Leptospira kirschneri in a high transmission urban setting for leptospirosis in Brazil.

Background: Leptospirosis is a zoonosis caused by pathogenic species of bacteria belonging to the genus Leptospira. Most studies infer the epidemiological patterns of a single serogroup or aggregate all serogroups to estimate overall seropositivity, thus not exploring the risks of exposure to distinct serogroups. The present study aims to delineate the demographic, socioeconomic and environmental factors associated with seropositivity of Leptospira serogroup Icterohaemorraghiae and serogroup Cynopteri in an urban high transmission setting for leptospirosis in Brazil. Methods/Principal Findings: We performed a cross-sectional serological study in five urban informal communities in the city of Salvador, Brazil. During the years 2018, 2020 2021, we recruited 2.808 residents and collected blood samples for serological analysis using microagglutination assays. We used a mixed-effect multinomial logistic regression model to identify risk factors associated with seropositivity for each serogroup. Seropositivity to Cynopteri increased with age in years (OR 1.03; 95% CI 1.01-1.06) and was higher in those living in houses with unplaster walls (exposed brick) (OR 1.68; 95% CI 1.09-2.59) and where cats were present near the household (OR 2.00; 95% CI 1.03-3.88). Seropositivity to Icterohaemorrhagiae also increased with age in years (OR 1.02; 95% CI 1.01-1.03) but was higher in males (OR 1.51; 95% CI 1.09-2.10), in those with work-related exposures (OR 1.71; 95% CI 1.10-2.66) or who had contact with sewage (OR 1.42; 95% CI 1.00-2.03). Spatial analysis showed differences in distribution of seropositivity to serogroups Icterohaemorrhagiae and Cynopteri within the five districts where study communities were situated. Conclusions/Significance: Our data suggests distinct epidemiological patterns associated with serogroups Icterohaemorrhagiae and Cynopteri within the high-risk urban environment for leptospirosis and with differences of spatial niches. Future studies must identify the different pathogenic serogroups circulating in low-income areas, and further evaluate the potential role of cats in the transmission of the serogroup Cynopteri in urban settings.

Prevalence of human leptospirosis in the Americas: a systematic review and meta-analysis / Prevalencia de la leptospirosis humana en las Américas: revisión sistemática y metanálisis / Prevalência da leptospirose humana nas Américas: revisão sistemática e metanálise

ABSTRACT Objective. To describe the prevalence of leptospirosis in the Americas. Methods. A systematic review and meta-analysis, in the period 1930 to 2017, performed on a search of six platforms: PubMed, Web of Science, Scopus, Lilacs, Embase, and Cochrane. Results. The search found 77 publications of which 53 (68%) were from the period 2000-2017. Of the 77, 62 studies were included in the analysis, from North America (11, 17%), Central America (9, 14%), and South America (42, 67%), and 22 studies were from urban areas. Leptospirosis prevalence in the 62 studies analyzed corresponded to 28% (95% CI [23, 32]). Countries with higher prevalence were United States of America (41%), Colombia (29%), and Brazil (21%). The most frequent serovars found were Icterohaemorrhagiae (43 of 77 publications, 55%), Canicola (35, 45%), Pomona (28, 36%), and Grippotyphosa (26, 33%). Conclusions. There is variability of Leptospira species and serovars with heterogenous distribution throughout the Americas, with high prevalence in some countries, highlighting the need for action to control the disease.

RESUMEN Objetivo. Describir la prevalencia de la leptospirosis en las Américas. Métodos. Revisión sistemática y metanálisis correspondientes al período 1930-2017, mediante una búsqueda en seis plataformas: PubMed, Web of Science, Scopus, Lilacs, Embase y Cochrane. Resultados. En la búsqueda se encontraron 77 publicaciones, de las que 53 (68%) eran del periodo 2000-2017. En el análisis se incluyeron 62 de los 77 estudios, correspondientes a América del Norte (11, 17%), Centroamérica (9, 14%) y América del Sur (42, 67%), y 22 estudios correspondientes a zonas urbanas. La prevalencia de la leptospirosis en los 62 estudios analizados fue del 28% (IC del 95% [23, 32]). Los países con mayor prevalencia fueron Estados Unidos de América (41%), Colombia (29%) y Brasil (21%). Las serovariedades más frecuentes fueron icterohaemorrhagiae (43 de 77 publicaciones, 55%), canicola (35, 45%), pomona (28, 36%) y grippotyphosa (26, 33%). Conclusiones. Se observa variabilidad de especies y serovariedades de Leptospira, con una distribución heterogénea en las Américas y una elevada prevalencia en algunos países, lo que pone de manifiesto la necesidad de adoptar medidas para controlar la enfermedad.

RESUMO Objetivo. Descrever a prevalência da leptospirose nas Américas. Métodos. Uma revisão sistemática e metanálise referente ao período de 1930 a 2017, realizada por meio de busca em seis plataformas: PubMed, Web of Science, Scopus, Lilacs, Embase e Cochrane. Resultados. A pesquisa encontrou 77 publicações, das quais 53 (68%) eram do período de 2000 a 2017. Dos 77 estudos, 62 foram incluídos na análise, da América do Norte (11, equivalente a 17%), América Central (9, equivalente a 14%) e América do Sul (42, equivalente a 67%), e 22 estudos foram realizados em áreas urbanas. A prevalência da leptospirose nos 62 estudos analisados correspondeu a 28% (IC 95% [23, 32]). Os países com maior prevalência foram os Estados Unidos da América (41%), a Colômbia (29%) e o Brasil (21%). Os sorovares mais frequentes encontrados foram Icterohaemorrhagiae (43 de 77 publicações, equivalente a 55%), Canicola (35, equivalente a 45%), Pomona (28, equivalente a 36%) e Grippotyphosa (26, equivalente a 33%). Conclusões. Há variabilidade nas espécies e sorovares de Leptospira, que têm distribuição heterogênea nas Américas e alta prevalência em alguns países, o que destaca a necessidade de ações para controlar a doença.

Evaluation of the impact of chemical control on the ecology of Rattus norvegicus of an urban community in Salvador, Brazil.

BACKGROUND: The presence of synanthropic rodents, such as Rattus norvegicus, in urban environments generates high costs of prophylaxis and control, in large part due to the environmental transmission of the pathogenic spirochete Leptospira interrogans, which causes leptospirosis. In Salvador, Brazil, The Center for Control of Zoonosis (CCZ) is responsible for planning and implementing Rodent Control Programs (RCP) which are based on chemical rodenticide. However, these strategies have not been standardized for use in developing countries. AIM: This study aimed to identify the effect of a chemical control campaign on the demographic variables of urban R. norvegicus, analyzing relative abundance, sex structure, body mass, and age of the population, as well as the characterization of spatial distribution among households, rodent capture campaigns and interventions. METHODS: This study was carried out during 2015 in three valleys of an urban poor community in Salvador. Individuals of R. norvegicus were systematically captured before (Pre-intervention) and three months (1st post-intervention) and six months (2nd post-intervention) after a chemical control intervention conducted by the CCZ in two valleys of the study area while the third valley was not included in the intervention campaign and was used as a non-intervention reference. We used analysis of variance to determine if intervention affected demographic variables and chi-square to compare proportions of infested households (Rodent infestation index-PII). RESULTS: During the chemical intervention, 939 households were visited. In the pre-intervention campaign, an effort of 310 trap nights resulted in 43 rodents captured, and in the 1st and 2nd, post-intervention campaigns resulted in 47 rodents captured over 312 trap nights and 36 rodents captured over 324 traps-nights, respectively. The rodent infestation index (PII) points did not show a reduction between the period before the intervention and the two periods after the chemical intervention (70%, 72%, and 65%, respectively). Regarding relative abundances, there was no difference between valleys and period before and two periods after chemical intervention (trap success valley 1: 0,18; 0,19; 0,18 / Valley 3 0,15; 0,17; 0,13/ P>0,05). Other demographic results showed that there was no difference in demographic characteristics of the rodent population before and after the intervention, as well as there being no influence of the application of rodenticide on the areas of concentration of capture of rodents between the campaigns. CONCLUSION: Our study indicates that the chemical control was not effective in controlling the population of R. norvegicus and provides evidence of the need for re-evaluation of rodent control practices in urban poor community settings.

Population dynamics of synanthropic rodents after a chemical and infrastructural intervention in an urban low-income community.

Synanthropic rodents are ubiquitous in low-income communities and pose risks for human health, as they are generally resistant to control programs. However, few or no studies have evaluated the long-term effect of chemical and infrastructural interventions on rodent population dynamics, especially in urban low-income communities, or evaluated the potential recovery of their population following interventions. We conducted a longitudinal study in a low-income community in the city of Salvador (BA, Brazil) to characterize the effect of interventions (chemical and infrastructural) on the dynamics of rodent population, and documented the post-intervention recovery of their population. We evaluated the degree of rodent infestation in 117 households/sampling points over three years (2014-2017), using tracking plates, a proxy for rodent abundance/activity. We reported a significant lower rodent activity/abundance after the chemical and infrastructural interventions (Z = -4.691 (p < 0.001)), with track plate positivity decreasing to 28% from 70% after and before interventions respectively. Therefore, the combination of chemical and infrastructural interventions significantly decreased the degree of rodent infestation in the study area. In addition, no rodent population rebound was recorded until almost a year post-intervention, and the post-intervention infestation level did not attain the pre-intervention level all through the study. Moreover, among pre-treatment conditions, access to sewer rather than the availability of food was the variable most closely associated with household rodent infestation. Our study indicates that Integrated Pest Management (IPM)-approaches are more effective in reducing rodent infestation than the use of a single method. Our findings will be useful in providing guidance for long-term rodent control programs, especially in urban low-income communities.

Household rat infestation in urban slum populations: Development and validation of a predictive score for leptospirosis.

Domestic rats are the principal reservoir for urban leptospirosis. However, few studies have identified infestation markers in slums and evaluated their predictivity for leptospirosis risk. We compared households with leptospirosis cases in Salvador, Brazil between 2007 and 2009 and their neighbors using a case control design, surveying for rodent infestation signs and environmental characteristics. With the 2007-2008 data, a conditional logistic regression modeling identified the peridomiciliar presence of rodent burrows (OR, 3.30; 95% CI, 1.50-7.26), rat feces (2.86; 1.24-6.59), runs (2.57; 1.06-6.22), households bordering abandoned houses (2.48; 1.04-6.02), and unplastered walls (2.22; 1.02-6.02) as risk factors and developed a predictive score for leptospirosis. With an independent data set from 2009, a receiver operating characteristic (ROC) curve analysis evaluated the prediction score performance, with the area under the curve being 0.70 (95% CI, 0.64-0.76) for score development and 0.71 (0.65-0.79) for validation. Results indicate that high proportions of urban slum households are infested with R. norvegicus. The score performed well when identifying high-risk households within slums. These findings need confirmation in other urban centers, but suggest that community-based screening for rodent infestation can allow to target rodent and environmental control measures in populations at highest risk for leptospirosis.

Molecular characterization of pathogenic Leptospira sp. in small mammals captured from the human leptospirosis suspected areas of Selangor state, Malaysia.

Leptospirosis is caused by the spirochetal bacterium Leptospira of which rodents are considered the most important reservoir. This study aims to determine and characterize virulent Leptospira species among rodents and small mammals found in human settlements and recreational spots within the Hulu Langat and Gombak districts of Selangor, Malaysia; regions that frequently report probable human leptospirosis cases. Molecular analysis revealed an overall Leptospira detection rate of 14.3% among the 266 small mammals captured, and the human settlements were found to have the highest number of isolates (15.1%), followed by recreational sites (14.5%). The molecular characterization conducted based on the lipL32, secY genes and MLST revealed that the strains belonged to four different species, including; Leptospira interrogans (29; 76.3%; ST50, ST238, ST243), L. kirschneri (5; 13.15%; ST110), L. borgpetersenii (3; 8%; ST143) and L. weilii (1; 2.63%; ST242). The study revealed genotypes of circulating strains among small mammals in Malaysia, which include Leptospira locus ST110 L. kirschneri, ST 50 L. interrogans, ST143 L. borgpetersenii and ST242 L. weilii. Among the small mammals studied, 17/105 (16.2%) Rattus norvegicus, 7/59 (11.9%) of Rattus rattus, 5/24 (20.8%) of Maxomys whiteheadi, 4/18 (22.2%) of Sundamys muelleri, 2/22 (9%), Tupaia gliss, 2/16 (12.5%) Rattus tiomanicus and 1/4 (25%) of Suncus murinus carried pathogenic leptospires. The data from the present study may imply that, in addition to rodents, other small mammals also serve as maintenance hosts for Leptospira. Hence, much remains unknown about Leptospira maintenance hosts, and there is need for further investigation to ascertain the prevailing serovars of pathogenic Leptospira in Malaysia. This will assist in the development of efficient diagnostic assays with improved microscopic agglutination test (MAT) panels, and in the implementation of suitable prevention and control measures.

Zoonoses As Ecological Entities: A Case Review of Plague.

As a zoonosis, Plague is also an ecological entity, a complex system of ecological interactions between the pathogen, the hosts, and the spatiotemporal variations of its ecosystems. Five reservoir system models have been proposed: (i) assemblages of small mammals with different levels of susceptibility and roles in the maintenance and amplification of the cycle; (ii) species-specific chronic infection models; (ii) flea vectors as the true reservoirs; (iii) Telluric Plague, and (iv) a metapopulation arrangement for species with a discrete spatial organization, following a source-sink dynamic of extinction and recolonization with naïve potential hosts. The diversity of the community that harbors the reservoir system affects the transmission cycle by predation, competition, and dilution effect. Plague has notable environmental constraints, depending on altitude (500+ meters), warm and dry climates, and conditions for high productivity events for expansion of the transmission cycle. Human impacts are altering Plague dynamics by altering landscape and the faunal composition of the foci and adjacent areas, usually increasing the presence and number of human cases and outbreaks. Climatic change is also affecting the range of its occurrence. In the current transitional state of zoonosis as a whole, Plague is at risk of becoming a public health problem in poor countries where ecosystem erosion, anthropic invasion of new areas, and climate change increase the contact of the population with reservoir systems, giving new urgency for ecologic research that further details its maintenance in the wild, the spillover events, and how it links to human cases.

Bat assemblage of Guaribas Biological Reserve, an Atlantic forest conservation unit in North-eastern Brazil: Results of a two-stage long-term survey / Assembleia de morcegos da Reserva Biológica de Guaribas, uma unidade de conservação da Mata Atlântica no Nordeste do Brasil: resultados de um estudo de longa duração em duas etapas

Inventories are the basis of every work with biodiversity, with increased importance due to the current environmental crisis. Bats are one of the most diverse groups of mammals, with high ecologic versatility and are good bioindicators to monitor environmental impacts. We performed a two-stage survey at an Atlantic Forest reserve in the State of Paraíba, the first stage registering 187 individuals of 24 species and the second stage, 1073 individuals of 11 species; the second stage's richness being a subset of the first as pointed by the Mann-Whitney test. The second stage was more efficient in accumulating individuals, while the first accumulated species more efficiently. The diversity estimation (Chao 1) pointed that the survey was efficient in registering 93.75% of the species richness predicted for the area, and that diversity estimators are more reliable to evaluate sampling efficiency than methods based in number of captures. The inventory survey registered over 42% of the species richness registered for the State of Paraíba, as well as included a new register, Natalus stramineus, pointing that the bat richness for the state is yet to be sufficiently studied.

Inventários são a base de qualquer trabalho com biodiversidade, com sua importância exacerbada dada a crise ambiental atual. Morcegos são um dos grupos de mamíferos mais diversos, com alta versatilidade ecológica, e se apresentam como bons bioindicadores para monitorar impactos ambientais. O presente trabalho é um inventário de morcegos em longo prazo, dividido em duas etapas, numa reserva biológica de Floresta Atlântica no Estado da Paraíba, Brasil. A primeira etapa capturou 187 indivíduos de 24 espécies, o segundo registrou 1073 indivíduos de 11 espécies, sendo a diversidade deste um subgrupo da diversidade do primeiro, como apontado pelo teste de Mann-Whitney. O segundo estágio foi mais eficaz em acumular indivíduos, enquanto o primeiro acumulou espécies mais eficientemente. O estimador de diversidade Chao 1 apontou que o inventário foi eficiente em registrar 93,75% da riqueza de espécies prevista para a área, e que estimadores de diversidade são mais confiáveis para avaliar suficiência amostral que métodos baseados em número mínimo de capturas. O inventário registrou cerca de 42% da riqueza de espécies conhecida para o Estado da Paraíba, assim como incluiu um novo registro, Natalus stramineus, ressaltando que a riqueza de espécies de morcegos no estado está por ser suficientemente estudada.

Assessing human-bat interactions around a protected area in northeastern Brazil.

BACKGROUND: Bats are key components to the Neotropical forests. Unfortunately, their bad reputation is a major obstacle in their conservation as it creates fear and hostility towards them. Understanding this reputation acquired by bats and studying interactions between bats and humans has shown fundamental promise when creating strategies to forge a non-antagonistic coexistence between both parts and in the promotion of bat conservation in areas with ever-rising human occupation. METHODS: Ninety people were surveyed from three villages that were situated around a Biological Reserve in the state of Paraiba; located in Northern Brazil. The survey was completed using semi-structured interviews addressing villager's knowledge of the biology and ecology of bats, their interactions with bats, potential medicinal uses, and their socioeconomic situation. Additionally, we sampled the bats that reside in or visit these villages. RESULTS: Bats were often considered harmful, dangerous and carriers of disease. Bats were often connected to hematophagia, as well. The respondents believe that impacts such as the deforestation are forcing bats into urban environments. With this research, we were able to register one of the few records of bats in popular medicine in Brazil. CONCLUSION: The folklore and superstition surrounding bats can form an obstacle that affects their conservation. Environmental education is an important step in order to create a harmonious coexistence between humans and bats and to mitigate the impending conflicts between humanity and nature.