Nucleic Acid Based Testing for HIV

Traditional testing for the human Immunovirus (HIV) has typically involved looking for antibodies against the virus to make a diagnosis. Antibodies are highly specific molecules generated by your body in response to the presence of invading pathogens, and as such are tested for as indicators of particular infections and diseases. Antibody testing is a staple of medical testing, however, when applied to HIV it can present with a few limitations. Nucleic Acid Testing is a relatively new method of detecting HIV which has been touted as a potential replacement for traditional antibody tests. In this article we look at why nucleic acid based tests, or NATs as they are also called, are being used more and more in modern medicine.

Why was NAT developed?

While antibody tests have been an effective tool in the diagnosis of HIV and many other conditions for many years, the process does have some limitations. Antibody tests are limited by their window period, which is a length of time after infection during which the test can’t be used reliably. The window period for antibody testing for HIV is hugely variable, lasting anywhere from 3 weeks to 6 months depending on a number of factors. For patients potentially suffering from the illness, waiting for such a long time before getting a concrete result can be very emotionally difficult. Similarly this delays clinical actions which can improve the outcome of the infection.


NAT techniques were developed as an alternative to antibody tests and one of their most astounding results is that they can reduce the window period to a matter of days. This is a huge step forward in the diagnosis and treatment of HIV, with many positive implications for patients.

How does NAT work?

Nucleic Acid Testing works by looking for particular sequences of nucleic acid which are specific to HIV. Every living organism possesses its own unique genetic material which acts as the blueprint that dictates any and all of its body’s workings. A virus is a very simple organism largely composed of this genetic material.

Genes are essentially specific sequences of nucleic acids which are unique to each organism, and by looking for the genes specific to HIV, NAT techniques can generate highly accurate results after a very short window period.

Where can I get NAT?

The usage of NAT for HIV is becoming increasingly widespread because of the reliability and efficiency of the procedure. NAT has been integrated into parts of the NHS including donor services which screen all blood samples for HIV to prevent its inadvertent transmission. The cost of NAT is higher than traditional antibody tests, which is why its use is not hugely prevalent as of yet.

You can get nucleic acid testing for HIV from private healthcare and online services if necessary, however as mentioned above, the procedure can be expensive. The antibody tests broadly used by healthcare services across the world remain highly effective methods of detecting and treating NAT.


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