The Singapore General Hospital (SGH) is in the midst of screening all other staff and patients who might have been exposed to hepatitis C.
Yesterday, the hospital revealed that 22 patients who were hospitalised for kidney problems between April and June had the disease.
Eight of them have since died, with four of the deaths linked to the viral infection. Another three died of unrelated causes, while one more death is pending investigation.
A total of 411 patients who passed through the affected wards between January and June this year are being screened. The number does not include the 22 patients who have already been diagnosed.
Those whose screening results do not reveal any abnormality will continue to be monitored by the hospital for a period of six months - the maximum known incubation period for the hepatitis C virus.
SGH has also screened all other patients who tested positive for abnormal liver function. Abnormal liver function can be caused by a hepatitis C infection.
However, no new hepatitis C cases related to admission outside the high-risk period of April to June this year were identified following these tests.
The hospital is also screening 42 doctors - including renal doctors, transplant surgeons and interventional radiologists - as well as 51 nurses who were directly involved in caring for the affected patients.
All staff have tested negative so far, said Professor Fong Kok Yong, who is chairman of SGH's medical board. He added that the hospital will also be recalling doctors who were formerly caring for the patients but have now been posted elsewhere.
The Health Ministry has also convened an independent review committee to scrutinise SGH's internal investigations and findings.
This committee will look for gaps or potential weaknesses in the current infection control system, as well as recommend safeguards that can be introduced, said Health Minister Gan Kim Yong yesterday.
"Our first priority is to extend our help and support for our patients, to ensure that their conditions are managed... and also provide support for the family members," he said.
"And our second priority is to look at how we can strengthen our precautionary measures and safeguards to ensure that this doesn't happen again."
Mr Gan said the committee would take about two months to complete its work, following which it would share the results with the public as well as the various healthcare clusters.
"We hope that SGH as well as all our healthcare institutions will learn from this incident and work hard to continue to improve our patient safety," Mr Gan said.
This article was first published on Oct 7, 2015.
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