In the latest development on the hepatitis C outbreak saga at the Singapore General Hospital's renal ward, some 1,000 people who have passed through the ward in the first six months of this year will be screened for the virus.
The hospital says it is getting in touch with those who had passed through the renal ward - both staff and patients - to come in for hepatitis C screening.
According to local news reports, eight of the 22 affected patients have died.
"Among these deaths, four are linked to the virus infection, while a fifth is under review," says the TODAY newspaper. "Two of the remaining 14 survivors are still warded."
The 1,000 people which SGH says will be involved in the test are a much higher number than the initial 411 which the hospital said, on Tuesday, it would be conducting tests on.
Professor Fong Kok Yong, chairman of SGH’s medical board, had told the media then, “We will be calling back patients who passed through the ward from January to June 2015, and to date, we’ve actually looked through all those who passed through and we’ve identified 411 of them, whom we’ll be calling back just to check.”
By 6pm on Thursday, the hospital had managed to contact 298 of these patients. 251 of them have fixed appointments. SGH said it has also screened 78 patients, as well as 169 staff.
As for the staff themselves, it is reported that 42 doctors and 51 nurses had "provided direct care to renal patients.” These staff members will also be screened, along with other doctors who covered the ward during the period.
While the cause of the outbreak is still unknown and is still being investigated, one possibility which has been raised is a lapse in the use of multi-dose vials.
For the uninitiated, a multi-dose vial “is a vial of liquid medication intended for parenteral administration (injection or infusion) that contains more than one dose of medication”, according to the United States Centers for Disease Control and Prevention (CDC).
The medication from each of such vials can also be shared by two or three patients.
Application of the medicine from such vials is made through the use of new needles and syringes each time, to prevent or avoid contamination.
According to the CDC website:
“Multi-dose vials should be dedicated to a single patient whenever possible.
"If multi-dose vials must be used for more than one patient, they should not be kept or accessed in the immediate patient treatment area. This is to prevent inadvertent contamination of the vial through direct or indirect contact with potentially contaminated surfaces or equipment that could then lead to infections in subsequent patients.
"If a multi-dose vial enters the immediate patient treatment area, it should be dedicated to that patient only and discarded after use.”
Singapore’s Ministry of Health (MOH) said on Wednesday that “both single-dose and multi-dose injection medication vials are used in our public hospitals.”
"Our public hospitals utilise multi-dose vials where the preparation is specifically formulated for such use, and governed by safety protocols,” the ministry added.
However, it also said in a statement on Wednesday that “it is not yet conclusive that the use of multi-dose vials is the cause of the Hepatitis C infection in this incident.”
Nonetheless, it explained that “as multi-dose vials are potentially at risk of contamination between uses, their safe use requires additional safety and infection prevention and control measures that staff have to comply with, such as opening only one vial of a particular medication at a time in each patient-care area, as recommended by WHO. Failure to comply to safety protocols may cause infection.”
The MOH has thus far convened an independent review committee to provide an “independent, objective and critical review of SGH’s report” which was submitted to the ministry in September, and to “review the work and findings of the two Committees convened by SGH to investigate this Cluster (i.e. the Medical Review Committee and Quality Assurance Review Committee)”, among other things in the Terms of Reference issued by the MOH to the committee.
It is, however, unclear if the authorities are also considering the possibility of intentional contamination, as some have pointed out.
“There’s of course also that possibility for the infection to have been caused intentionally, i.e. it was malicious or sabotage,” wrote blogger Zit Seng.
Thus far, there has neither been any indication that this has happened, nor have the police been brought in to investigate any possible criminal act with regard to the hepatitis C outbreak.
But with the cause or causes of the outbreak unknown, nothing should be ruled out.