Jellyfish Envenomation Events in Selected Coastal Provinces of Thailand 1998-2008

ABSTRACT

Background: Lethal jellyfish envenomation has occurred sporadically in Thailand for years, but limited data exists describing the public health burden of envenomation, or the presence of the most dangerous types of jellyfish (Cubazoan,or box jellyfish) in Thailand.  We conducted an investigation to study morbidity and mortality of jellyfish envenomation, identify species and implement prevention measures. Methods: A descriptive study was conducted by medical records review in 2 coastal provinces. A case was defined as a jellyfish envenomation injury documented by a medical professional from 2003-2008. Events were analyzed by place, time, age, gender and severity. Jellyfish specimens were collected by local fishermen and speciated by marine biologists. Results: From 2003-2008, 54 cases occurred, including 1 death. Of cases, 49% were 21-40 years old; median age was 26 years. Thai to foreigner ratio was 2.61; male to female ratio was 11.2.  The most frequent sites of attack were leg (28.7%), forearm (15.1%), foot (12.3%) and hand (12.3%). Symptoms included burning pain (36.7%), pain (26.5%) and respiratory discomfort (18.4%). Signs included erythema (51.2%), burning (19.5%) and swelling (12.2%). Twenty-three percent required hospitalization. Number of events peaked in April for Trat and May for Krabi province. Of 12 jellyfish specimens collected from Trat, marine biologists identified all as Cubazoan (box jellyfish).  Conclusion: Jellyfish envenomation is a significant public health problem in the coastal provinces. Global warming could increase the scope of this problem.  Based upon this investigation, the Bureau of Epidemiology is developing public health jellyfish warnings for four coastal provinces. Vinegar, which denatures the cysts which contain venom, should be available in all beach areas.  Fishermen should wear long sleeves and gloves.