Ethno-knowledge and attitudes regarding snakebites in the Alto Juruá region, Western Brazilian Amazonia.

BACKGROUND: The Alto Juruá region, located in the extreme western part of the Brazilian Amazonia, possesses an indigenous and riverine population which is involved in agricultural and forest extraction activities, and is a region that stands out for its high incidence of snakebites. OBJECTIVES: To assess the attitudes of the victims, the characteristics of the snakes and the circumstances of the snakebites which occurred in a region where human populations are highly exposed to snakes. METHODS: The study was conducted at the Regional Hospital of Juruá in the Municipality of Cruzeiro do Sul (Acre), which regularly attends victims of snakebites in the Alto Juruá region. The snakes that caused the envenomations were identified from clinical and epidemiological diagnosis of the symptoms and signs that patients presented during hospital, and by enzyme immunoassay for venom detection using serum samples of the patients, or by identification of the snake responsible for the envenomation when it was taken to the hospital or photographed. People who suffered or witnessed the snakebite were interviewed to assess the circumstances of the bite, the attitude adopted after the accident and whether they recognized the species of snake that caused the envenomation. RESULTS: There were 133 cases of snakebite (76.24/100.000 inhabitants), mainly involving male individuals living in the rural area and who had a low level of education. The most affected groups were farmers (48%) and children and teenagers (39%). It was observed that 8.3% of them presented a history of recurrence for bites. The lower limbs were the most affected anatomical region (84%). The Bothrops atrox snake, mainly small specimens (mostly juveniles), was the main species involved in the envenomations (83.4%). Snakebites occurred mainly in forest areas, backyards of houses in rural areas and near to aquatic environments, during activities (walking, farming, extractivism, hunting). Most of the time, the snake was on the ground and the bite occurred because of the approximation of the individual, either by trampling or by approximation of a hand. Half of the victims performed some kind of inadequate first aid (not drinking water, use of tourniquet, incision at the site of the bite, use of black stone, drinking a compound "Específico Pessoa"). CONCLUSIONS: Snakebite is an important cause of morbidity in the Alto Juruá region. Bothrops bites are mostly caused by small-sized specimens, probably due to the greater abundance of B. atrox juveniles, and also because small snakes are more difficult for people to see. People are more often bitten on the lower limbs probably due to the size of B. atrox (small and medium) and because the snakes are usually on the ground in most situations. Many victims resort to ineffective actions that can cause complications and also delay serotherapy. A low level of education is a factor that may contribute to worse outcomes in snakebites since it is associated with a lack of knowledge of preventive and first aid measures.

Envenomation by Micrurus annellatus bolivianus (Peters, 1871) coral snake in the western Brazilian Amazon.

Bites by Micrurus snakes in Brazilian Amazon represent about 0.4% of snakebite registered in that area. There is not information available about the M. annellatus snakebites In this report, we describe a case of envenoming caused by Micrurus annellatus bolivianus recorded in the municipality of Cruzeiro do Sul, state of Acre, western Brazilian Amazon. On admission, the patient was suffering from mild pain, mild edema and paraesthesia restricted to the site of the bite, darkened vision and nausea. Laboratorial evaluation revealed unclottable blood which improved only after 3 days of follow-up. Envenoming was classified as moderate, and 50 ml of antielapid serum was administered. The next day after the incident, vital signs were normal and the patient had mild thrombocytopenia (133,000/mm3). The patient did not present any bleeding during the hospitalization. On the fourth day after admission, the patient was discharged alleging no complaints. The patient showed coagulopathy, a rare condition in cases of Micrurus bites. Some areas where there is a lack of knowledge on coral snakebites are listed in this manuscript.

Stepping into a dangerous quagmire: Macroecological determinants of Bothrops envenomings, Brazilian Amazon.

Despite significant and successful efforts in Brazil regarding snakebites in the areas of research, antivenom manufacture and quality control, training of health professionals in the diagnosis and clinical management of bites, little is known about determinants of snakebites incidence in order to further plan interventions to reduce the impact of this medical condition. Understanding the complexity of ecological interactions in a geographical region is important for prediction, prevention and control measures of snakebites. This investigation aims to describe spatial distribution and identify environmental determinants of human envenoming by lancehead pit vipers (Bothrops genus), in the Brazilian Amazon. Aggregated data by the municipality was used to analyze the spatial distribution of Bothrops bites cases and its relationship with geographic and environmental factors. Eight geo-environmental factors were included in the analysis as independent variables: (1) tree canopy loss increase; (2) area with vegetation cover; (3) area covered by water bodies; (4) altitude; (5) precipitation; (6) air relative humidity; (7) soil moisture; and (8) air temperature. Human envenoming by lancehead pit vipers (Bothrops genus) in the Amazon region is more incident in lowlands [Adjusted regression coefficient [ARC] -0.0007 (IC95%: -0.001; -0.0006), p<0.0001], with high preserved original vegetation cover [ARC 0.0065 (IC95%: 0.0071; 0.0060), p<0.0001], with heaviest rainfall [ARC 0.0001 (IC95%: 0.00009; 0.0001), p<0.0001] and higher air relative humidity [ARC 0.0082 (IC95%: 0.0108; 0.0056), p<0.0001]. This association is interpreted as the result of the higher prey availability and further abundance of pit vipers in such landscapes.