3 We summarize and review current knowledge on life-threatening jellyfish stings in Thailand, hoping this report will provide a stimulus for improved awareness and management of jellyfish problems throughout Southeast Asia. Two kinds of potentially deadly jellyfish are confirmed in Thai waters: chirodropid box jellyfish and Irukandji box jellyfish (L. Gershwin, unpublished

data). Hundreds of other species of jellyfish are also present but are not considered as life threatening. Chirodropids are large box-shaped jellyfish Antiinfection Compound Library supplier (ie, “box jellyfish”) with multiple tentacles arising from each of the four lower corners of the bell. Irukandji are easily distinguished from chirodropids, as their box-shaped body has just a single tentacle at each lower corner. Chironex kill by massive envenomation, causing respiratory arrest or cardiac arrest in systole in as little as 2 to 3 min. Their stings have caused multiple human fatalities throughout the Indo-Pacific, including the Maldives,

southern India, Myanmar, the Malaysian archipelago (east and west coasts), Indonesia, Brunei, Sarawak, Sabah, the Philippines and Solomon Islands, Okinawa (Japan), and Australia (Nakorn, Selleck Sunitinib personal communication).3-8 At least two confirmed Irukandji deaths have occurred in Australia, probably more, given that the sting leaves little or no mark, and later symptoms resemble acute myocardial infarction (AMI), cerebrovascular accident, or even drowning.9-11 Irukandji syndrome has also been confirmed from Hawaii, Florida, the Caribbean, North Wales (UK), New Guinea, and throughout the tropical Pacific.5,6,9 Chirodropids appear mainly in the summer months in the

northern and southern hemispheres, usually during the local rainy or monsoonal season, and most commonly around sandy beaches near mangrove areas. Their season is longest at the equator, where it can last all year, and reduces moving toward both Tropics. Irukandji are also commonest in the warmer months, although seasonal patterns of some different species9 in Australia have been recorded all months of the year and are probably similar elsewhere.12 Sting case histories were gathered from a variety of sources: PubMed searching keywords “Thailand” and “jellyfish” Bacterial neuraminidase provided four relevant publications; most case histories were obtained through Thai physicians, Divers Alert Network reports, witnesses, media, and e-mail contacts. These reports are certainly a significant underestimation of the true occurrence of fatal or severe stings in Thailand. Diagnoses of “box jellyfish sting” and “Irukandji syndrome” were made by standard acceptance. Chirodropids—causing sudden severe skin pain, obvious severe whip-like skin marks (often on the legs from shallow water), rapid reduction of consciousness, and life-threatening breathing and/or cardiac problems.