Fernanda A. G. Andrade

Serological investigation of rabies virus neutralizing antibodies in bats captured in the eastern Brazilian Amazon.

BACKGROUND In 2004 and 2005 a total of 38 cases of human rabies transmitted by the hematophagous bat Desmodus rotundus were registered in the Brazilian state of Pará; 23 (60.5%) cases occurred in the northeastern region. Because of this, a serological investigation for the antibodies of rabies virus was performed in municipalities of the northeastern state of Pará, in order to assess whether the virus was circulating among different bat species. METHODS Bats were collected in 2009 with mist-nets during the rainy and dry seasons and blood samples were collected for the serological survey. RESULTS A total of 307 serum samples were obtained representing 28 bat species. The number of seropositives was high (50.8%, 156/307) and was significantly higher during the rainy season (67.4%, 95/141). No significant difference in rates was found between male and female or adult and juvenile. Seropositive individuals were recorded in 24 species sampled, the most prominent being Artibeus planirostris, with 52.2% (24/46) positive individuals. CONCLUSION The serological proportion reported in this paper in a large numbers of individuals indicates that the rabies virus circulates quite actively in the study region, but, because of the production of antibodies, the expression of the disease in these individuals is low.

Rabies in humans and non-human in the state of Pará, Brazilian Amazon

We evaluate the relationship of positive cases of rabies with the continuing expansion of livestock production, and analyse the trends of this zoonosis in human population in the state of Pará, Brazilian Amazon. The distribution of rabies cases was recorded between 1999 and 2004. Of 148 cases of rabies, 21% were in humans and 79% in non-human mammals. The rapid growth in livestock numbers seems to be associated with the increase of positive cases in bovine livestock transmitted by vampire bats. This idea is supported by positive and significant relationship of both events in time (p<0.01), but failed when spatial distribution among regions of the state was considered. However, rabies cases tend to occur toward the northeastern of the state of Pará, where rabies cases are proportionally five times greater than other mesoregions, suggesting that increased livestock production may influence the increase of this zoonosis.

A Range Extension for the Yellow Armadillo, Euphractus sexcinctus Linnaeus, 1758 (Xenarthra: Dasypodidae), in the Eastern Brazilian Amazon

Los osos hormigueros (Myrmecophaga tridactyla) son insectívoros estrictos y tienen un intestino delgado que es siete veces el largo del cuerpo y un intestino grueso similar en longitud al cuerpo. Opuestamente a lo que se podría deducir, debido a que el peludo es más omnívoro en cuanto a sus hábitos alimenticios, el intestino delgado y el grueso del peludo en estudio es en relación al cuerpo relativamente más corto (5,7 y 0,91 veces el largo del cuerpo) que el de los osos hormigueros (7 y 1 veces el largo del cuerpo respectivamente) y el de las mulitas (Dasypus sabanicola) (8,29 y 0,825 veces el largo del cuerpo respectivamente), según datos de Stevens y Hume (1995). Considerando otros omnívoros podríamos citar al oso negro (Ursus americanus), cuyo intestino es aproximadamente diez veces el largo del cuerpo, sin distinción entre intestino medio y grueso (Stevens y Hume, 1995). No obstante, para poder determinar la razón por la cual el peludo tiene intestinos relativamente cortos, teniendo en cuenta sus hábitos alimenticios, deberíamos tener más datos que confirmen estas dimensiones. Ya que si estos datos se repitieran podríamos suponer que estamos frente a un animal que solo consume hierbas cuando no tiene otros alimentos disponibles, es decir un verdadero oportunista.

Comparison between the chiropteran fauna from terra firme and mangrove forests on the Bragança peninsula in Pará, Brazil

The aim of this study is to compare the density and diversity of the chiropteran fauna of the terra firme and mangrove forests of the Bragança peninsula in the Brazilian state of Pará. Bats were captured using mist nets every 2 months, resulting in the collection of 217 specimens from the terra firme and 221 from the mangrove. There was no significant difference between sites in the number of individuals or diversity. Thus, while the terra firme forest is probably the principal source of fruit, the mangrove seems to be the secondary source for opportunistic species during the period of scarcity. O objetivo deste estudo é comparar a densidade e a diversidade da fauna de quirópteros das florestas de terra firme e de manguezal da península bragantina no Estado do Pará, Brazil. Morcegos foram capturados com redes‐neblina a cada dois meses, resultando na coleta de 217 espécimes provenientes da terra firme e 221 do manguezal. Não existe diferença significativa entre os sítios de trabalho no que se refere ao número de indivíduos ou diversidade. Por isso, enquanto a floresta de terra firme é provavelmente a fonte principal de fruto, o manguezal parece ser a fonte secundária para as espécies oportunistas durante o período de escassez.

Geographical Analysis for Detecting High-Risk Areas for Bovine/Human Rabies Transmitted by the Common Hematophagous Bat in the Amazon Region, Brazil

Background The common hematophagous bat, Desmodus rotundus, is one of the main wild reservoirs of rabies virus in several regions in Latin America. New production practices and changed land use have provided environmental features that have been very favorable for D. rotundus bat populations, making this species the main transmitter of rabies in the cycle that involves humans and herbivores. In the Amazon region, these features include a mosaic of environmental, social, and economic components, which together creates areas with different levels of risk for human and bovine infections, as presented in this work in the eastern Brazilian Amazon. Methodology We geo-referenced a total of 175 cases of rabies, of which 88% occurred in bovines and 12% in humans, respectively, and related these cases to a number of different geographical and biological variables. The spatial distribution was analyzed using the Kernel function, while the association with independent variables was assessed using a multi-criterion Analytical Hierarchy Process (AHP) technique. Findings The spatiotemporal analysis of the occurrence of rabies in bovines and humans found reduction in the number of cases in the eastern state of Pará, where no more cases were recorded in humans, whereas high infection rates were recorded in bovines in the northeastern part of the state, and low rates in the southeast. The areas of highest risk for bovine rabies are found in the proximity of rivers and highways. In the case of human rabies, the highest concentration of high-risk areas was found where the highway network coincides with high densities of rural and indigenous populations. Conclusion The high-risk areas for human and bovine rabies are patchily distributed, and related to extensive deforested areas, large herds of cattle, and the presence of highways. These findings provide an important database for the generation of epidemiological models that could support the development of effective prevention measures and controls.

Bat fauna of the Cerrado savanna of eastern Maranhão, Brazil, with new species occurrences

In Brazil, 179 bat species have been recorded to date, representing 68 genera and nine families. Few data are available on the bat fauna of the state of Maranhao, so the present study was based on a survey of the bat fauna of the Inhamum Municipal Environmental Protection Area (APA Inhamum) in the Cerrado savanna of the eastern extreme of the state. This inventory provides new records of bat species for the state of Maranhao and the Cerrado biome. A total of 31 species (four families) were collected, representing 39% of the bat species known to occur in Maranhao and 28.71% of the species described for the Cerrado. The family Phyllostomidae was the most diverse, with 23 species (74.20% of the total), and also the most abundant, with 86.09% of the specimens collected. The Molossidae (four species) was the second most diverse, followed by the Vespertilionidae (three species) and the Emballonuridae (one species). Carollia perspicillata was the most abundant species (28%).The records of Artibeus fimbriatus and Platyrrhinus fusciventris are the first for the Cerrado and were also recorded in Maranhao for the first time. The cumulative species curve did not reach an asymptote. The species Dermanura gnoma, Lasiurus blossevillii, Lasiurus ega, Micronycteris schmidtorum, Molossops temminckii, Platyrrhinus cf. recifinus, Phylloderma stenops and Trachops cirrhosus, were also recorded in Maranhao for the first time demonstrating the value of for mammal inventories and emphasizing the need for further surveys in this poorly-known region.

VIROLOGICAL AND SEROLOGICAL DIAGNOSIS OF RABIES IN BATS FROM AN URBAN AREA IN THE BRAZILIAN AMAZON

The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005, in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a priority area for studies on this zoonosis. Given this, the present study provides data on this phenomenon in an urban context, in order to assess the possible circulation of the classic rabies virus (RABV) among bat species in Capanema, a town in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and dry seasons. Samples of brain tissue and blood were collected for virological and serological survey, respectively. None of the 153 brain tissue samples analyzed tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum samples analyzed were seropositive. Artibeus planirostris was the most common species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31 52.60%). Statistically, equal proportions of seropositive results were obtained in the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95% CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested positive for infection, the high proportion of seropositive specimens indicates that RABV may be widespread in this urban area.

Spatial and Temporal Analysis of Attacks by Common Vampire Bats (Desmodus rotundus) on Humans in the Rural Brazilian Amazon Basin

This article attempts to investigate the effects of the notification of wounds caused by Desmodus rotundus in humans in the rural zone of the eastern Brazilian Amazon basin. We analyzed data on bat attacks for the period between 2007 and 2012, provided by the Pará State Secretariat for Municipal Public Health (SMS) and the Pará State Agricultural Defense Agency (ADEPARA). We recorded 121 attacks in humans in the municipality of Pacajá, in 28 localities, including both rural and urban areas. Urban cases accounted for almost a fifth (19.8%) of all records. No significant variation was found in the number of cases recorded each year (H = 7.28, d.f. = 5, P = 0.20), although significant variation was found in the spatial distribution of the reports (Q = 17.08, d.f. = 5, P < 0.01), reflecting the heterogeneity of the occurrence of attacks. Our conclusion is that the major reduction in the number of reported attacks on humans by hematophagous bats in the municipality of Pacajá is a positive result of the notification by the local people to the public health authorities, which appears to be an effective tool of the prophylactic scheme to control this epizootic in the rural zone of the Brazilian Amazon basin.

Phylogeography of the Dark Fruit-Eating Bat Artibeus obscurus in the Brazilian Amazon

Artibeus obscurus (Mammalia: Chiroptera) is endemic to South America, being found in at least 18 Brazilian states. Recent studies revealed that different populations of this genus present distinct phylogeographic patterns; however, very little is known on the population genetics structure of A. obscurus in the Amazon rainforest. Here, using a fragment (1010bp) of the mitochondrial gene cytochrome b from 87 samples, we investigated patterns of genetic divergence among populations of A. obscurus from different locations in the Brazilian Amazon rainforest and compared them with other Brazilian and South American regions. Analysis of molecular variance (AMOVA), fixation index (Fst) analysis, and phylogeographic patterns showed divergence between two major monophyletic groups, each one corresponding to a geographic region associated with the Atlantic and Amazon forest biomes. The Atlantic forest clusters formed a monophyletic group with a high bootstrap support and a fragmented distribution that follows the pattern predicted by the Refuge Theory. On the other hand, a different scenario was observed for the Amazon forest, where no fragmentation was identified. The AMOVA results revealed a significant geographic heterogeneity in the distribution of genetic variation, with 70% found within populations across the studied populations (Fst values ranging from 0.05864 to 0.09673; φST = 0.55). The intrapopulational analysis revealed that one population (Bragança) showed significant evidence of population expansion, with the formation of 2 distinct phylogroups, suggesting the occurrence of a subspecies or at least a different population in this region. These results also suggest considerable heterogeneity for A. obscurus in the Amazon region.

Parâmetros demográficos de Micoureus demerarae (Didelphidae, Marsupialia) em áreas contíguas de manguezal e terra firme, Bragança, Pará, Brasil

Este estudo investigou alguns variaveis populacionais da especie Micoureus demerarae (Thomas, 1905), que incluem: densidade, recrutamento e sobrevivencia. Sendo que, os especimes coletados foram obtidos em dois ecossistemas contiguos, manguezal e terra firme da denominada Fazenda das Salinas, a qual esta localizada proxima ao municipio de Braganca, no nordeste do Estado do Para. Para tanto, foram abertas duas transeccoes em cada ambiente destinadas as coletas realizadas de novembro de 2002 a setembro de 2003. Os resultados definiram uma populacao aberta com distribuicao uniforme para os individuos do manguezal e agregada para os da terra firme, alem de evidente sazonalidade, com maior proporcao de machos na terra firme. O periodo reprodutivo foi o parâmetro mais importante para a flutuacao populacional no inicio da estacao seca. Os impactos ambientais sobre os parâmetros da dinâmica populacional de M. demerarae parecem ser determinantes na manutencao dessas populacoes da Fazenda das Salinas.