Dirofilaria immitis, a parasite that mainly infects domestic or wild canids, but can infect felines or humans as well, is frequent in many Brazilian areas. The main objective of this research was to determine the prevalence of natural canine infection at the Algodoal-Maiandeua Island complex, in the coastal region of the state of Pará, Brazil. A total of 67 dogs were sampled for blood microfilariae detection and for D. immitis DNA detection. Microfilaria and D. immitis DNA could be detected in 35.8% (24/67) of the animals. In one dog’s sample no microfilariae were detected, but the PCR was positive, suggesting that either larvae recently were eliminated or adults died shortly before sample collecting. Therefore, it can be concluded that the occurrence of D. immitis is a health threat for domestic and wild canids at the Island of Algodoal, as well as for feline or human health.

Rabies is an important zoonosis to public health associated with lethal encephalitis and economic losses. Analysis of its spatial distribution is a meaningful tool in understanding its dispersion, which may contribute to the control and prophylaxis of the disease. This study analyzed the spatial-temporal distribution of rabies outbreaks in livestock in Pará state, Brazil, from 2004 to 2013. We used records of neurological syndromes obtained from the state’s livestock authority (Adepará). The analysis recorded 711 neurological syndromes reports in livestock, of which 32.8% were positive for rabies. In 8% of the neurological syndromes (n=57) was not possible to perform the analysis because of bad-packaging conditions of the samples sent. Outbreaks involved at least 1,179 animals and cattle were the most affected animal species (76.8%). The numbers of reported neurological syndromes and of rabies outbreak shad strong positive correlation and exhibited decreasing linear trend. Spatially, most outbreaks occurred in two mesoregions in Pará (Northeast and Southeast). One of the justifications for this spatial distribution may be related with the distribution of the animals in the state, since these mesoregions are the largest cattle producers in Pará and have most of their territory deforested for pasture implementation.

An outbreak of human rabies transmitted by hematophagous bats occurred in 2018 in the state of Pará, Brazil, eastern Amazon, after 14 years with no record of the disease. It is necessary to understand the epidemiological characteristics of these attacks to protect the local population. This study aimed to characterize attacks of humans by vampire bats in the municipality of São João da Ponta, Pará state, Brazil, from 2013 to 2015. All individuals attacked by bats who sought medical care during the study period (n=5) were identified in the Notifiable Diseases Information System (SINAN) database and answered a questionnaire about the circumstances of the attack. Using snowball sampling, seed cases identified other individuals who were attacked in the same period but did not seek medical care (n=61), totalizing 66 people attacked in the same period. The interviewees were male (92.4%), adults between 20 and 50 years old (69.6%) and had completed elementary education (86.3%). Most were rural residents (92.4%) and crab fishermen (79.3%). The interviewees (92.4%) identified the mangrove of the Mãe Grande de Curuçá extractive reserve as an area conducive to attacks by vampire bats, where groups of fishermen sometimes concentrate for days for crab fishing, often living in improvised dwellings without walls and covered by tarps or straw (88.8%). The wounds were single bites (71.2%) and were located on the lower limbs (93.9%). Overall, 42.4% of participants had been bitten more than four times throughout their life (range 1-23 attacks). Participants were unaware of the risk of contracting rabies by the bite (95.4%). Using São João da Ponta as a model, this study shows that bat attacks are an essentially occupational problem in the study region. Indeed, for each reported attack, there are 12.2 unreported cases. It is necessary to develop strategies to reach this population for prophylactic treatment. Author Summary: Different from which occurs worldwide in relation to rabies transmission, in Amazon region, vampire bat is involved on direct transmission of rabies virus to humans when searching for bloodmeal. It is common in the state of Pará, Eastern Amazon, large areas inhabited near forests and mangroves. People living there use forest natural resources as a way of income and sustenance and these working conditions is what our study points out as an important factor for aggressions predisposition. Here this subject is shown as an occupational problem. This study also quantified for the first time underreported human’s aggressions by bats in Amazon, using the snowball sampling, which valued the relationship between individuals to reach the target population. Based on these results, rabies surveillance may direct actions for prevention and health education for these individuals, including changes in notifications forms and suggesting pre-exposure prophylaxis in vaccination calendar of the Brazilian Ministry of Health for these individuals exposed to the rabies virus.