AIIMS advocates special test to make blood transfusion safer

New Delhi, Nov 21 : About 20,000 patients in India could be at risk of getting infected blood -- unknown to them and even the donors. Doctors at the premier All India Institute of Medical Sciences (AIIMS) here Saturday advocated a special test to detect Hepatitis B and C and HIV so that blood transfusion becomes a lot safer in India.

Armed with a study to show that the current system of blood screening could be a bit risky, doctors said the Nucleic Acid Amplification Test (NAT) -- which is common in Europe, the US and Asian countries like Singapore, Thailand and Malaysia -- would make it more precise and safe to detect these viruses.

"At present Enzyme-linked Immunosorbent Assay (ELISA test) is used to check for infections in donor bloods according to a Supreme Court Order made in the year 2000. This test detects the disease only after the viruses in the blood have proliferated to a certain degree," Kavita Chatterjee, faculty-in-charge of the blood bank at AIIMS, told reporters.

"NAT, which is a molecular test, can actually detect the virus even before it has started multiplying by amplifying the viral genetic materials," she added.

Chatterjee, who conducted the survey on 5,818 donor samples throughout the country for the presence of HIV, Hepatitis B and C, found that there were five such cases where NAT detected infection that could not be detected by ELISA.

"We compared the NAT tests with the standard testing methods and found that it is difficult to identify the viruses during the 'window period' -- where the virus is still multiplying in the body but the donor may not be aware and donates the infected blood. But NAT can do it," she said.

"Moreover each bag of donated blood collected can be transfused in up to three patients. And so with 7.4 million blood donations collected annually in India, it means more than 6,000 donations could adversely affect around 20,000 patients and families," she said.

The study advocates for the implementation of this test throughout the country so that the window period -- the time period between viral infection and viral detection -- is significantly decreased.

"This is the best test to ensure maximum possibility of viral interception," Chatterjee said.

Agreeing with Chatterjee's findings, Kanjaksha Ghosh, director of the Mumbai-based Institute of Immunohaematology, said: "This test should be made mandatory across India in addition to ELISA to decrease the spread of these blood transfused diseases."

While the ELISA test is for Rs.15 in government hospitals, the NAT costs Rs.800.

--IANS