Travellers to Ko Mark off Trat province have been warned to watch out for box jellyfish and, if they want to swim in the sea, must swim within the zones cordoned off with fishing nets to prevent the jellyfish from getting in.
The warning was issued by Marine and Coastal Resources Department after some holidaymakers were stung by box jellyfish while they were swimming in the sea of Ko Mark.
Mr Chatuporn Burutpat, director-general of the department, said over the weekend that marine officials conducted an extensive survey of the sea around Ko Mark during March 22-23 and found large numbers of box jellyfish of the Chironex family floating in the sea near the beaches of the island.
However, he said that no box jellyfish was found in the safe zones in front of Ko Mark resort and Prompakdi resort which were surrounded with fishing nets.
Mr Chatuporn said that the presence of box jellyfish in the sea at this time of the year was normal and he recommended tourists to wear proper swimming suits which protect most parts of the body and to avoid swimming outside the netted areas.
In case of getting stung by a box jellyfish, the victim must quickly get out of the sea and wash the area that was stung with vinegar, and not with water, for about 30 seconds and do not rub the area with hand or anything.
He asked tourism operators to warn their tourists of where they should swim or not to swim and provide them with basic information about what to do when stung by box jellyfish.
According to the Epidemiology Office of the Department of Disease Control, eight people died from box jellyfish stings during 1999-2015. In 2015 alone, 194 people were stung by box jellyfish in six provinces and, of these, two died. The province recorded the highest incidence of box jellyfish sting was Petchaburi, with 143 cases, followed by 27 cases in Surat Thani with two deaths, eight cases each in Trat and Satun, six in Pattani and two in Krabi.