SINGAPORE - The Singapore General Hospital (SGH) has apologised for an outbreak of the hepatitis C virus in one of its renal wards, which has led to 22 patients being infected with the virus.

Of the 22, four - who were also ill with other serious conditions - have since died.

At a media briefing on Tuesday (Oct 6) afternoon, the hospital said it had noted an increased frequency of hepatitis C virus infections (from an average of two to four infections per year to five in a few weeks) in early June in the ward.

It prompted SGH to step up urgent checks for the virus in patients with abnormal liver function test results staying in the same ward.

Investigations into the cause of the infections are ongoing, but initial checks have indicated that the source could be attributed to "intravenous (IV) injectable agents".

In a separate statement, the Ministry of Health (MOH) said it has set up an independent review committee, tasked to determine if SGH had taken all possible measures to identify the possible lapses, as well as remedy any weak points in the overall workflow with regard to infection control.

Health Minister Gan Kim Yong said: "I am gravely concerned and disappointed with the occurrence of the cluster of hepatitis C cases in SGH. My thoughts are with the affected patients and families.

"MOH takes this incident very seriously...I have decided to appoint an independent review committee to provide added assurance that there is an objective and critical review of the internal findings by SGH."

Hepatitis C, which causes chronic liver cancer, is mainly transmitted through blood-to-blood contact associated with IV drug use, poorly sterilised equipment and transfusions.

About 0.3 per cent of the general population in Singapore suffer from it.

SGH chief executive officer Ang Chong Lye said: "We would like to apologise unreservedly for the grief, pain and anguish this has caused our patients and their families.

"Patient safety is non-negotiable. What happens to our patients is always our responsibility. We will spare no effort in reviewing our processes and examining all possible sources of infection to prevent recurrence."

Prof Ang added that SGH is in touch with the affected patients and their families, and will "continue to provide full support and the appropriate care in managing their condition".

The 22 patients were admitted and stayed in the newly-renovated Ward 67 between April and June this year. Ward 64A, the original renal ward, was under renovation.

All were suffering from some form of renal disease, with the majority having undergone renal transplants.

Professor Fong Kok Yong, chairman of the SGH medical board, stressed that while there has been no conclusive evidence to what caused the infections, the hospital had taken "aggressive" steps to rectify any shortcomings detected during the ongoing investigations.

SGH has since taken added precautions to fortify its infection control measures, including "stopping long established and accepted practices in healthcare institutions" such as multi-dosing.

The hospital's renal care team, including doctors and nurses, have undergone hepatitis C screening. The screening will also be extended to other doctors who covered the ward during the affected period.

Meanwhile, SGH has been contacting patients who were admitted to Wards 64A and 67 from the start of the year to June for screening.

No new hepatitis C cases related to admission outside the affected April-June period have been identified.