Background. Northern Thailand's biggest botulism outbreak to date occurred on 14 March 2006 and affected 209 people. Of these, 42 developed respiratory failure, and 25 of those who developed respiratory failure were referred to 9 high facility hospitals for treatment of severe respiratory failure and autonomic nervous system involvement. Among these patients, we aimed to assess the relationship between the rate of ventilator dependence and the occurrence of treatment by day 4 versus day 6 after exposure to bamboo shoots (the source of the botulism outbreak), as well as the relationship between ventilator dependence and negative inspiratory pressure.

Methods. The investigators reviewed the circumstances and timing of symptoms following exposure. Mobile teams treated patients with botulinum antitoxin on day 4 or day 6 after exposure in Nan Hospital (Nan, Thailand). Eighteen patients (in 7 high facility hospitals) with severe respiratory failure received a low- and high-rate repetitive nerve stimulation test, and negative inspiratory pressure was measured.

Inclusions:

• Ate the bamboo shoots in Banluang district, on March,14 2006
• Clinical of respiratory failure and need ventilator assistant
• Needed to referred to other hospital
• The staffs of referred hospital willing to participate in the Thai Botulism study group

Exclusion Criteria:

• Patients who did not eat bamboo shoots in Banluang district on March14,2006.
• No clinical of respiratory failure.
• Not referred to other hospital.