Blood transfusions suspected in 29 hepatitis cases

Twenty-nine sufferers of hepatitis-B virus (HBV) or hepatitis-C virus (Hepatitis C Virus) may have been infected through blood transfusions conducted across the country in the April-June period, the Health, Labor and Welfare Ministry warned Tuesday.

A highly sensitive testing method was used to examine the donor blood, but when the recipients were subsequently examined using the same method, 28 of them tested negative to the viruses even though they were confirmed sufferers.

The ministry explained that even though the method, which was developed in 1999, is highly regarded, it cannot detect such viruses in all cases.

"Although the method is of great precision, it's not perfect. When blood donors test positive, we'll (continue to) check the dates they donated their blood and quickly dispose of it," a ministry official said.

The ministry recently examined the April-June period of reports it receives from medical institutions across the country on side effects of treatment. It found that 11 patients may have contracted HBV through blood products used in blood transfusions, and that another 18 may have contracted Hepatitis C Virus.

Traditional methods cannot detect HBV and Hepatitis C Virus in recently infected blood because it contains only small numbers of antibodies and viruses.

In 1999, the Japanese Red Cross Society introduced a more sensitive nucleic acid amplification testing (NAT) method that can detect even a small number of viruses by amplifying genes they contain.

The method was used to examine the blood of the 29 people who had contracted HBV and Hepatitis C Virus, but 28 of them tested negative to the viruses.

It has been pointed out that even NAT can overlook hepatitis and HIV in contaminated blood if tests are conducted shortly after infection.

However, the ministry has not received any report that HIV-contaminated blood has passed NAT, officials said. (Mainichi Shimbun, Japan, July 15, 2003)