Findings of investigation into death of PMH doctor released
The Centre for Health Protection (CHP) of the Department of Health today (May 30) completed its investigation into the acute gastroenteritis incident involving three oncologists at Princess Margaret Hospital (PMH) and confirmed that the illnesses of the three doctors were not related. The CHP thanked the expert team from the Department of Microbiology at the University of Hong Kong (HKU), led by Professor Yuen Kwok-yung, for their assistance during the investigation.
On February 10, 2025, the CHP received a notification from PMH that three doctors in its oncology department had developed acute gastroenteritis symptoms and one of them unfortunately passed away on February 7. PMH's preliminary investigation revealed that a stool sample from one of the doctors, who had mild symptoms, tested positive for Shiga toxin genes bynucleic acid testing. Therefore, it was suspected that the cluster might be associated with Shiga toxin-producing Escherichia coli (STEC) infection. The CHP immediately conducted a comprehensive epidemiological investigation of the suspected cluster. A team of experts from the Department of Microbiology of the HKU, led by Professor Yuen, also assisted in the investigation.
The CHP's investigation revealed that the bacterial culture of the stool sample from the doctor suspected of having an STEC infection but with mild symptoms did not grow any viable STEC bacteria. Samples from the other two doctors, including the deceased doctor, were negative for STEC. The CHP collected 34 environmental samples and 27 food samples from the oncology department and relevant food premises at PMH, all of which were negative for STEC. The CHP also enhanced surveillance on the staff of the oncology department of PMH, and no other related cases were detected. Based on the available information, the CHP confirmed that there was no STEC outbreak in the oncology department of PMH and that there was no linkage between the illnesses of the three doctors.
The pathology department of PMH has conducted an autopsy and pathological examination on the cause of death of the deceased doctor. However, the post-mortem examination could not determine the exact cause of the pathological changes that led to his death. Experts from the Department of Microbiology of the HKU have detected group C rotavirus (a known rotavirus) in various tissue samples of the deceased using nucleic acid testing. However, the virus was not detected in the stool samples of the other two doctors. The experts were of the view that the initial acute gastroenteritis in the deceased was caused by group C rotavirus. The direct relationship between group C rotavirus and the cause of death was uncertain, while other contributing factors could not be ruled out.
Rotavirus is a gastroenteritis virus commonly found in children and is classified into groups A, B and C, etc. Group A is the most common (accounting for over 90 per cent of rotavirus infections worldwide), mainly affecting children under the age of 5. Scientific studies indicate that group C may infect adults and older children more frequently, with milder symptoms compared to groups A and B. According to the statistics of the Hospital Authority, there have been no deaths from rotavirus infection in public hospitals in the past 10 years. Preventive measures for rotavirus infection are similar to those for other viral gastroenteritis. It is important to maintain good personal, food and environmental hygiene.
Separately, Escherichia coli (E. coli) is a bacterium commonly found in the intestines of humans and warm-blooded animals. Most strains of E. coli are harmless. Some strains, however, such as STEC, can produce strong toxins and cause severe foodborne disease. Generally, STEC infections are often associated with consuming contaminated food or water, such as raw or undercooked meat, contaminated fruits and vegetables, or unpasteurised dairy products. Meanwhile, the bacteria can also be transmitted from person-to-person through the faecal-oral route. Preventive measures for STEC infection are similar to those recommended for other foodborne diseases.
