A utilização de acaricidas sintéticos é a forma mais comum para o controle do carrapato-do-boi, Rhipicephalus (Boophilus) microplus. Porém, os problemas acarretados pelo o uso indiscriminado desses produtos têm impulsionado a busca por métodos alternativos como a utilização de compostos a base de plantas medicinais. Nesse contexto, este estudo objetivou avaliar a eficácia de diferentes métodos de extração do fumo de corda (Nicotiana tabacum) contra ovos de R. microplus. Para a obtenção dos extratos da planta, foram utilizadas as seguintes técnicas: maceração, destilação e extração de Soxhlet, todas utilizando a água como solvente. Os ovos foram organizados em alíquotas de 100 mg para serem tratados com os extratos e, posteriormente, observados diariamente para o registro dos parâmetros relativos à eclosão larval. Observou-se um aumento significativo no período de incubação quando foram utilizados os extratos obtidos por maceração ou Soxhlet. O período e o percentual de eclosão foram significativamente reduzidos, com a utilização de qualquer uma das técnicas de extração. Portanto, o extrato aquoso de N. tabacum, sem a necessidade de formulações, é eficaz para impedir a eclodibilidade larval sob as condições empregadas nesta pesquisa.

Outbreaks of human rabies transmitted by hematophagous bats occurred in 2018 in Pará state, Brazil, eastern Amazon, after 12 years of no record of the disease. Thus, it is necessary to understand the epidemiological characteristics of these attacks to protect the local population. This study aimed to characterize the bat bite populations in the municipality of São João da Ponta, Pará State, Brazil, in 2013-2015. The Notifiable Diseases Information System (SINAN) database was used to identify the five individuals who sought medical care during the study period (seeds).Other individuals who were attacked during the same period but did not seek medical care (n = 61) were reached by snowball sampling, and a descriptive analysis was performed based on information obtained from questionnaires. Majority of the interviewees were men (92.4%; 61/66) and adults aged 20-50 years (69.9%; 46/66) and had <4 years of formal school education (86.3%; 57/66). Additionally, most of them were rural residents (92.4%; 61/66) and crab fishermen (79.3%; 53/66). The interviewees (92.4%; 61/66) identified mangroves of the Mãe Grande de Curuçá extractive reserve, where groups of fishermen sometimes gather for several days for crab fishing, often living in improvised dwellings without walls and covered by tarps or straw (88.8%; 56/66), conducive to attacks by vampire bats. Overall, 42.4% (28/66) of the participants had been bitten more than four times throughout their life. The median number of attacks over the participant's lifetime was 3.11 (range, 1-23). Participants were unaware of the risk of contracting rabies from the bite (95.4%; 65/66). These results suggest that vampire bat attacks are essentially an occupational hazard in the study region. Moreover, for each reported attack, there were at least 12.2 unreported cases. Thus, the study highlights the need to develop strategies for prophylactic treatment of this population.