Experts investigating the cases at Princess Margaret Hospital’s oncology department in Kwai Chung said on Tuesday that they believed the doctors could have been infected after eating contaminated food, but there was no evidence they had shared meals or visited the same catering areas.
“A food source is not a small possibility,” said Professor Yuen Kwok-yung, chair of infectious diseases at the University of Hong Kong’s department of microbiology, who was involved in the investigation.
He said contaminated water was unlikely to be the source of the infections as the level of chlorine in the city’s water was high enough to act as a disinfectant.
Yuen said investigators were yet to determine whether the Shiga toxin-producing E coli, a highly toxic strain of the bacteria, had killed the doctor, who had a good health record.
The strain was found in a stool sample from one of the infected oncologists who had milder symptoms.
