Nucleic Acid Testing (NAT) is a molecular technique used for screening blood donations. It can detect early-stage infectious agents such as HIV, hepatitis-C and hepatitis-B by looking at genetic markers of viruses (DNA and RNA), making it a highly sensitive tool.
Normally, blood screening for viruses is done through serological tests that search for antibodies. These sometimes may not show up in early stages of an infection.
Experts said the prevalence of HIV in blood donors is 0.5%. In the general population, the prevalence of hepatitis-B is between 2% and 8%, and for hepatitis-C, it is about 2%. So far, Madhya Pradesh, Jammu & Kashmir and Odisha have synced NAT with all blood banks in the states. Elsewhere, the technology has been adopted by the AIIMS-Delhi and the Christian Medical College-Vellore.
Dr Diptiranjan Rout, assistant professor at the department of transfusion medicine, AIIMS in NCI Jhajjar, spoke about the risk of spreading infections through transfusions. “The risk of any of these infections is multiplied three-four times as the single unit (of blood donated) is broken into three or four components, and transfused into patients depending on their need,” he said.
On adoption of NAT, he said: “NAT detects early-stage infectious agents and helps maximise safety. All health centres conducting blood transfusion should ideally adopt this.” The doctor said the antibodies for an infection are normally detected in serological (blood) tests about 20 to 80 days after a virus invades. With NAT, this time period is reduced to 3-20 days. He added that NCI is the first facility in Haryana to incorporate this technology.