All of the patients who contracted botulism from contaminated processed bamboo shoots are now safe and will be allowed home within the month, a senior official at the Public Health Ministry said yesterday, adding that the World Health Organisation (WHO) has praised Thailand's successful treatment of the mass poisoning.

Acting permanent secretary

for public health Dr Prat Boonyawongwirot told a press conference yesterday that just 34 botulism patients remain in hospital, with 23 cases still dependent on respiratory aids. However, their conditions show distinct improvement and they should be released in 10 to 20 days, Prat said.

About 137 people in Nan's Ban Luang district were hospitalised with botulism after eating bamboo shoots contaminated with clostridium botulinum toxin at a merit-making ceremony on March 14.

Prat said the incident represented the world's largest mass botulism poisoning and Thailand's success in treating the patients has been praised by the WHO, with a number of other countries also sending experts to study preventative methods in order to avoid similar cases.

Disease Control Department director-general Thawat Suntrajarn thanked all parties, from both overseas and inside the country, who collaborated on the project which lead to the swift delivery of botulism antitoxin serum.

"The antitoxin is the key and patients must receive it within 72 hours to minimise the risk of complications," he said, adding that Thailand had used 88 of the 103 doses of antitoxin donated, and the rest would be kept at Nan Hospital for emergencies.

Botulism patient Wanida Porjai, who was discharged from Ratchavithi Hospital, thanked her doctors, the Public Health Ministry and related agencies for curing her.

"I couldn't move, couldn't speak for days. I thought I'd die, but everyone helped with my hospitalisation, and ultimately gave me a new life," she said.