About 160 students fell ill after eating a meal at the Samukkee Pattana School in Mae Fah Luang district of the northern province last Wednesday, according to local media reports.
About 100 students of the school for hilltribe children in Therd Thai sub-district near the Myanmar border were sent to Mae Fah Luang, Maechan and Chiang Rai Prachanukroh hospitals from Thursday to Saturday. They suffered from diarrhoea, vomiting and dehydration.
A Prathom 4 schoolgirl identified as Daokrajai Muelae, 12, of the Akha hilltribe, died on the way to Mae Fah Luang Hospital. Thirty-seven students remained in hospital on Saturday.
About 470 students had gathered at the school on Wednesday for activities on the occasion of the Buddhist Lent. They received free boxes of Hainanese chicken rice at lunch and began experiencing symptoms the following day.
Surasak Namphao, a local teacher, said the students regularly received such free meals, but he believes the tap water they drank may have caused the illness. He said the filter on the tap water dispenser had not been changed for a long time and the water was murky.
However, Mae Fah Luang district chief Worayan Boonnarat said he believed the chicken rice boxes, which all came from the same supplier, were the cause.