
The test result, however, found it was a different type from the one that killed the student.
The student fell ill after eating at the restaurant with her friends on November 15 and died on November 23.
Dr Surasing Wisarutrat, deputy chief of the health office, said the bacteria found in the food samples could be dangerous to pregnant women, the elderly, those with chronic ailments, organ-transplant recipients or chemotherapy patients.
He also noted that the food sample was taken four days after the incident. Authorities would continue to probe where the killer bacteria came from and consult related experts in the investigation.
As for three other streptococcus patients hospitalised around the same time, Surasing said the initial inquiry found that two of them had eaten raw pork, so the office would collect pork samples from markets for testing.