Description of the situation
22 March 2006
On 17 March, WHO received reports of a possible outbreak of botulism in northern Thailand (Nan Province) among guests at a festival who had eaten home-preserved bamboo shoots. Although antitoxin for the treatment of botulism is only available in some countries, WHO was able to ensure delivery of antitoxin to Thailand by the morning of 19 March.
As of 20 March, the Ministry of Public Health (MOPH) established that 152 of the 170 people attending a local village Buddhist festival in Banluang District, Nan Province, had developed symptoms suggestive of botulism (dysphagia, dysarthria, ptosis, abdominal discomfort, muscle weakness). All of the affected people had eaten pickled bamboo shoots prepared in a traditional manner, with symptoms developing and progressing over 24-48 hours following consumption. One hundred of the 152 people were hospitalized, and 40 have since required intubation and respirator support. To date, no deaths have been reported.
The local health office has traced and recalled the suspect cans of locally produced bamboo shoots and is providing public education on food safety. WHO is working closely with the MOPH, local technical partners and the US Centers for Disease Control and Prevention (CDC) on laboratory investigation in support of case diagnosis, investigation, and foodborne disease investigation and surveillance. A case control and cohort study is under way to describe the outbreak in detail.
To date, 80 doses of antitoxin (20 from the United Kingdom, 50 from CDC Atlanta and 10 from Sanofi-Pasteur Canada) have been provided, and severely affected patients are being treated. The Japanese National Institute of Infectious Disease is planning to deliver another 23 doses of antitoxin to Thailand today.