What is Nucleic Acid Test (NAT)?

The Supreme Court of India has agreed to examine whether blood banks across the country should mandatorily conduct the Nucleic Acid Test (NAT) to detect infections in donated blood.

A Bench headed by Chief Justice of India Surya Kant, along with Justices Joymalya Bagchi and Vipul M. Pancholi, raised questions regarding the cost-effectiveness of NAT compared to the widely used ELISA test during the hearing.

Petition Before the Court

The case was brought by the NGO Sarvesham Mangalam Foundation. Its counsel, advocate A. Velan, argued that safe blood transfusion is an essential component of the right to life under Article 21 of the Constitution of India.

The petitioner urged the court to consider making NAT testing mandatory in blood banks to ensure safer transfusions and reduce the risk of infection.

What is Nucleic Acid Test (NAT)?

NAT is a highly sensitive molecular diagnostic technique used to detect the genetic material (DNA or RNA) of viruses in blood samples.

It is capable of identifying infections such as:

• HIV/AIDS
• Hepatitis B
• Hepatitis C

Unlike conventional tests, NAT can detect viruses at a very early stage, even before antibodies are formed in the blood.

NAT vs ELISA

The court also discussed the cost and practicality of NAT compared to the commonly used Enzyme-Linked Immunosorbent Assay (ELISA) test.

Feature	NAT	ELISA
Detection method	Detects viral genetic material	Detects antibodies or antigens
Detection window	Earlier detection	Slightly longer window period
Sensitivity	Very high	Moderate
Cost	More expensive	Cheaper and widely used