Snakebites in “Invisible Populations”: A cross-sectional survey in riverine populations in the remote western Brazilian Amazon

Abstract

In the Brazilian Amazon, long distances, low healthcare coverage, common use of ineffective or deleterious self-care practices, and resistance to seeking medical assistance have an impact on access to antivenom treatment. This study aimed to estimate snakebite underreporting, and analyze barriers that prevent victims from obtaining healthcare in communities located in 15 municipalities on the banks of the Solimões, Juruá and Purus Rivers, in the remote Western Brazilian Amazon. Information on the participants’ demographics, previous snakebites, access to healthcare, time taken to reach medical assistance, use of self-care practices, and the reason for not accessing healthcare were collected through semi-structured interviews. In the case of deaths, information was collected by interviewing parents, relatives or acquaintances. A total of 172 participants who reported having suffered snakebites during their lifetime were interviewed. A total of 73 different treatment procedures was reported by 65.1% of the participants. Participants living in different river basins share few self-care procedures that use traditional medicine, and 91 (52.9%) participants reported that they had access to healthcare. Living in communities along the Juruá River [OR = 12.6 (95% CI = 3.2–49.7; p<0.001)] and the use of traditional medicine [OR = 11.6 (95% CI = 3.4–39.8; p<0.001)] were variables that were independently associated to the lack of access to healthcare. The main reasons for not accessing healthcare were the pprioritization of traditional treatments (70.4%), and the failure to recognize the situation as being potentially severe (50.6%). Four deaths from complications arising from the snakebite were reported, and three of these were from communities on the banks of the Juruá River. Only one of these received medical assistance. We found an unexpectedly high underreporting of snakebite cases and associated deaths. Snakebite victims utilized three main different healing systems: 1) self-care using miscellaneous techniques; 2) official medical healthcare generally combined with traditional practices; and 3) self-care using traditional practices combined with Western medicines. To mitigate snakebite burden in the Brazilian Amazon, an innovative intervention that would optimize timely delivery of care, including antivenom distribution among existing community healthcare centers, is needed. Many patients bitten by snakes in the Brazilian Amazon do not seek medical care since they live great distinces from health facilities and often do not have the financial resources to travel in search of assistance. In this situation of vulnerability, a wide variety of traditional methods, without proven efficacy, and some known to be harmful, are used by individuals. As a result, many cases of snakebites that are not treated in the official health network are consequently not reported to the epidemiological surveillance system, thus generating underreporting. Knowing the proportion of underreported cases and their hostspots is very important for planning interventions that will improve the coverage of the healthcare network and the logistics of delivery of antivenoms. In a pioneering way in Brazil, this study was carried out to estimate snakebite underreporting and analyze obstacles that prevent victims from obtaining healthcare in the communities located in 15 municipalities on the banks of the Solimões, Juruá and Purus Rivers, in the remote Western Brazilian Amazon. Cases of deaths due to snakebites were also investigated. A total of 172 participants who reported having suffered snakebites during their lifetime were interviewed, as well as the circumstances of 4 deaths. Most patients recalled using some traditional medicine in the form of self-care to treat snakebite. In total, there were 73 different treatment procedures, which were quite different between the different regions studied. Almost half of the participants did not seek medical advice, claiming as reason for that the prioritization for traditional treatments and the non-regognition of the situation as potentially severe. In the Juruá River communities, this frequency was around 70%. The preference of traditional medicine was also associated with the lack of access to healthcare. We believe that this situation will only be mitigated if the antivenoms are made available closer to snakebite victims, i.e., in riverside and rural health units.