Population-based study of venomous snakebite in Taiwan

Abstract

The epidemiological features of snakebite are fragmented and inadequate in most countries. The true impact of snakebite is also very likely to be underestimated, and reliable information on its incidence, morbidity, and mortality is limited worldwide. We perform a nationwide epidemiological study of snakebite by extracting claim record data from Taiwan's National Health Insurance database to explore the epidemiology of venomous snakebite from years 2005 to 2009. A total of 4647 snakebites were reported in 2005–2009. The nationwide annual incidence of snakebite was 40.49 per million persons. Hemorrhagic-type snakebites (Viridovipera stejnegeri and Protobothrops mucrosquamatus) accounted for 71.78% of the cases, while neurotoxic-type snakebites (Naja atra and Bungarus multicinctus) accounted for 19.21%. Only a few cases of snakebites were caused by Deinagkistrodon acutus (0.73%). Although the east part of Taiwan accounted for only one-sixth of the total number of cases, the same area had the highest incidence of snakebite, about seven times the national incidence. Fifty-nine percent (n = 2747) of victims were between the age of 41 years and 70 years, and mostly in the age group of 51–60 years (n = 1026, 22%). The highest incidence (130.4 per million persons) was in the age group of 71–80 years. In general, snakebite victims suffered minor injuries. Overall, hospital admission was 35.8%, and only about 3.6% patients were needed to be admitted to the intensive care unit. During this study period, only two cases of mortality were documented. In this population-based study, the annual incidence of venomous snakebite was 40 per million people. Cases of venomous snakebite are geographically unevenly distributed in Taiwan. Due to effective antivenom therapy, the outcome of the snakebite patients was favorable.