Nationwide and long-term epidemiological research of snakebite envenomation in Taiwan during 2002–2014 based on the use of snake antivenoms: A study utilizing National Health Insurance Database

Abstract

Introduction In Taiwan, six venomous snake species with medical importance have been found; however, long-term epidemiological data of snakebite envenomation (SBE) is lacking. This study aimed to explore the epidemiology of SBE based on the distribution and use of different antivenoms in different parts of Taiwan to facilitate the development of prevention strategies and resource allocation. Methods and results This retrospective study was conducted using the Taiwan National Health Insurance Research Database from 2002 to 2014. A total of 12,542 patients were treated with antivenoms. The directly standardized cumulative incidence was 3.6 cases per 100,000 individuals based on the 2000 World Standard Population. The incidence of SBEs peaked in the summer (35.9%). The relative risk (RR) of male patients versus female patients was 2.5 (p < 0.0001). The RRs of patients aged 18–64 and ≥65 years versus those aged <18 years were 6.0 (p < 0.0001) and 14.3 (p < 0.0001), respectively. Furthermore, the RR of eastern Taiwan versus northern Taiwan was 6.8 (p < 0.0001). The RR of agricultural workers versus laborers was 5.5 (p < 0.0001). Compared with patients envenomed by Trimeresurus stejnegeri stejnegeri or Protobothrops mucrosquamatus, those envenomed by Naja atra or Bungarus multicinctus multicinctus were more likely to occur in central (adjusted odds ratio [aOR] = 2.6, p < 0.0001) or southern (aOR = 3.2, p < 0.0001) Taiwan, but less frequently among agricultural workers (aOR = 0.6, p < 0.0001). The overall case-fatality rate was 0.11%. Conclusions Among Asian countries, Taiwan had low incidence and case-fatality rates of SBE. Risk factors included male gender, old age, summer season, being in eastern Taiwan, and being an agricultural worker. Differences of the epidemiological findings between snake species should be focused on when developing strategies for snakebite prevention.

In vitro immunoreactivity and in vivo neutralization of Trimeresurus gracilis venom with antivenoms targeting four pit viper species

“…Only 0.6% of the envenomation events were associated with D . acutus [ 6 ]. As of now, there have been only two case reports of envenomations by O .…”

“…acutus envenomation is usually associated with hemorrhagic bullae or necrosis, prolonged PT/activated partial thromboplastin time, thrombocytopenia, and patients can be administered two to four vials of the monovalent antivenom against D . acutus (DaAV) initially [ 5 , 6 , 8 , 10 , 11 ]. In O .…”

“…In Taiwan, majority (73.3%) of envenomation events were associated with T. stejnegeri and P. mucrosquamatus, with case-fatality rates of 0.09%, during 2002-2014 based on the use of snake antivenoms [6]. Among Asian countries, Taiwan reported low incidence and case-fatality rates of snakebite envenomation, which might be due to easy access to modern medicine, immediate availability of antivenoms in healthcare facilities, few adverse effects of antivenoms, and prompt surgical intervention [6]. Only 0.6% of the envenomation events were associated with D. acutus [6].…”

“…Among Asian countries, Taiwan reported low incidence and case-fatality rates of snakebite envenomation, which might be due to easy access to modern medicine, immediate availability of antivenoms in healthcare facilities, few adverse effects of antivenoms, and prompt surgical intervention [6]. Only 0.6% of the envenomation events were associated with D. acutus [6]. As of now, there have been only two case reports of envenomations by O. makazayazaya [3,4] and two case reports of envenomations by T. gracilis in Taiwan [5].…”

“…In P. mucrosquamatus envenomation, bullae or necrosis is present, but coagulopathy and thrombocytopenia are uncommon. Patients can be administered two to four vials of TsPmAV initially and the median total dose of the specific antivenom was 5.5 vials [5][6][7][8][9]. D. acutus envenomation is usually associated with hemorrhagic bullae or necrosis, prolonged PT/ activated partial thromboplastin time, thrombocytopenia, and patients can be administered two to four vials of the monovalent antivenom against D. acutus (DaAV) initially [5,6,8,10,11].…”