Severity of Scorpion Stings in the Western Brazilian Amazon: A Case-Control Study

Abstract

BackgroundScorpion stings are a major public health problem in Brazil, with an increasing number of registered cases every year. Affecting mostly vulnerable populations, the phenomenon is not well described and is considered a neglected disease. In Brazil, the use of anti-venom formulations is provided free of charge. The associate scorpion sting case is subject to compulsory reporting. This paper describes the epidemiology and identifies factors associated with severity of scorpions stings in the state of Amazonas, in the Western Brazilian Amazon.Methodology/Principal FindingsThis study included all cases of scorpion stings in the state of Amazonas reported to the Brazilian Diseases Surveillance System from January 1, 2007 to December 31, 2014. A case-control study was conducted to identify factors associated with scorpions sting severity. A total of 2,120 cases were reported during this period. The mean incidence rate in the Amazonas was 7.6 per 100,000 inhabitants/year. Scorpion stings showed a large spatial distribution in the state and represent a potential occupational health problem for rural populations. There was a positive correlation between the absolute number of cases and the altimetric river levels in the Central (p<0.001; Rs = 0.479 linear) and Southwest (p = 0.032; linear Rs = 0.261) regions of the state. Cases were mostly classified as mild (68.6%), followed by moderate (26.8%), and severe (4.6%). The overall lethality rate was 0.3%. Lethality rate among children ≤10 years was 1.3%. Age <10 years [OR = 2.58 (95%CI = 1.47–4.55; p = 0.001)], stings occurring in the rural area [OR = 1.97 (95%CI = 1.18–3.29; p = 0.033) and in the South region of the state [OR = 1.85 (95%CI = 1.17–2.93; p = 0.008)] were independently associated with the risk of developing severity.Conclusions/SignificanceScorpion stings show an extensive distribution in the Western Brazilian Amazon threatening especially rural populations, children ≤10 in particular. Thus, the mapping of scorpions fauna in different Amazon localities is essential and must be accompanied by the characterization of the main biological activities of the venoms. Urban and farming planning, in parallel with awareness of workers at risk for scorpion stings on the need for personal protective equipment use should be considered as public policies for preventing scorpionism.

Scorpion stings and spider bites in the Upper Juruá, Acre – Brazil

“…The mean of the morbidity coefficient (12 cases/100,000 inhabitants) during the period of this study was higher than that of some municipalities in the neighboring state of Amazonas (4 cases / 100,000 inhabitants) reported by Sampaio et al 6 and lower than in other municipalities, Rio Preto da Eva (91 cases/100,000 inhabitants) and Apuí (58 cases/100,000 inhabitants), also in Amazonas state. Incidents with scorpions had an average of 29.28 cases /100.00 inhabitants, being higher than that registered for the Amazonas state (7.6 cases/100,000 inhabitants), which presents higher incidence levels in two of its municipalities, Rio Preto da Eva (58.9 / 100,000 inhabitants) and Apuí (182.6 cases/100,000 inhabitants) 5 .…”

“…The majority of cases reported were scorpion stings (164 cases, 70%), which is the most frequent at the national level 1,2 and also in studies conducted in other regions of the country 5,6,[11][12][13] . However, the mean incidence of cases of spider bites (12 cases) and scorpion stings (29.28) recorded per 100,000 inhabitants in this study for Cruzeiro do Sul is much higher than that reported for Brazil (2.9 and 16.7, respectively) and in the state of Acre (3.85 and 4.58) by Chippaux 2 .…”

“…In the Amazon, spider bites and scorpion stings have been studied more in the eastern region and the central region 5,6 , with a relative scarcity of publications regarding the western region. In the state of Amazonas, the main municipalities with records of spider bites are: Rio Preto da Eva with 91 cases per 100,000 inhabitants, followed by Apuí with 58 cases and other municipalities with a frequency of 4 cases per 100,000 inhabitants 6 , for the scorpion stings, the state of Amazonas has an average population of 7.6 cases / 100,000 inhabitants, where the highest records were in Apuí with 182 cases followed by Rio Preto da Eva with 58.9 cases / 100,000 inhabitants 5 .…”

Incidence Prevalence Clinical Overview and Cost Analysis of Pediatric Poisoning Cases in a Tertiary Care Setting of Berhampur, Odisha, India.

“…Similarly, scorpion stings are a major public health problem in underdeveloped tropical and subtropical countries, especially Sahelian Africa, South India, the Middle East, Mexico, and South Latin America. [21,34] Annually 1.2 million scorpion stings occur worldwide, leading to 3250 deaths (0.27%) [12]. For every person killed by poisonous snake, ten are killed by a poisonous scorpion.…”

Implication of Tityus apiacas (Lourenco, 2002) in scorpion envenomations in the Southern Amazon border, Brazil

“…Scorpion stings incidents show an extensive distribution in the Brazilian Amazon and represent a potential health problem for rural communities 3 . In this region, risk of developing severity was significantly higher in children and, interestingly, in stings occurring in the Apuí region of the Southern Amazon 3 .…”