HIV RNA / DNA PCR Test – Nucleic Acid Amplification Testing (NAAT)
HIV RNA / DNA PCR Test
a.k.a Nucleic Acid Amplification Testing (NAAT)
The HIV RNA test has revolutionized HIV screening especially for people at high risk.
The test directly measures the amount of HIV virus in a person’s blood.
This same test is also used to monitor how a person with HIV is responding to treatment. When used this way, it is called a Viral Load test.
The HIV RNA test is deemed to be 100% conclusive if done after 10 to 12 days from the date of exposure.
There are some theories that say this test becomes less accurate from about 3 months post exposure. This is because at 3 months post exposure, the body would have made antibodies to fight the HIV virus. Therefore, the amount of virus in the blood may drop below the detection limit of the RNA test.
Acute HIV infection is very challenging to identify because its symptoms are not specific and antibody tests often are either still negative or indeterminate. However, this is also the time when an infected person is most contagious due to a high viral load. Detection of acute HIV infection not only enables us to counsel the patient on taking active steps to reduce transmission, it also enables us to better identify potentially infected partners as the time span we need to focus on is still relatively short.
Currently the vast majority of HIV tests are conducted using antibody tests. These include rapid tests such as Oraquick™ (Rockeby) and Determine™ (Abbott) and also conventional blood ELISA tests.
The limitation of antibody tests is the window period. Antibody tests may not be able to pick up HIV infections for up to 3 months after an individual is infected. This is far from ideal because this is exactly the period that a person is most infectious with the highest viral load. Acute HIV infection contributes disproportionately to HIV transmission due to its high viral load and negative antibody tests.
NAAT tests for HIV require only 10 days post exposure to be accurate. It is the only option for detecting HIV infection before seroconversion.Click here for HIV Testing FAQ
Benefits of NAAT include:
- Earlier identification of infected persons leading to reduced transmission risks
- Facilitate partner identification, counseling and testing
- Early diagnosis leads to early initiation of follow up and treatment leading to better prognosis
However, NAAT increases the cost and turnover time for HIV testing.
A screening program for Acute HIV Infection using pooled NAAT was successfully conducted by the New York City Department of Health and Mental Hygiene1. Specimens from all patients whose rapid HIV antibody test was negative were tested by polymerase chain reaction in pools of 512 specimens. If the pool was positive, component specimens were tested to identify which specimen(s) contained HIV RNA. The report findings confirmed that pooled NAAT can increase Acute HIV Infection diagnoses among high risk STD patients. It can also be used to identify areas or populations in which HIV infection is spreading.
The usual turnaround time is 2 weeks.
However, the Lab can conduct an expedited test for a surcharge.
If you wish to have a HIV RNA test done, please come down to our clinic.
There is no preparation like fasting necessary.Click here to see the full range of our HIV/STD Services
Need more advice?
- Robertson Walk (Anonymous HIV Clinic) (+65 6238 7810)
- DUO Galleria (Bugis MRT) (+65 6976 5023)
- Novena Medical Centre (+65 6397 2095)
- Somerset – Orchard Building (+65 6262 0762)
- Raffles Place – PLUS (+65 6962 7144)
- Holland V (+65 6235 1339)
- Siglap (East Coast Road) (+65 6962 2144)
Where to find us – here
Selected clinics are open on Saturday and Sunday.
For lady patients who prefer female doctors, we have professional certified female Doctors to attend to your medical needs.
Our Andrology and Infection Centre at Novena Medical Center is open.Call us at 63972095 now to book your appointment.Feel free to email your queries, feedback and suggestions on what other topics you want to see in the comments section below.If you have any questions, visit our free online forum on sexual health, HIV and STDs.1. CDC. MMWR, November 27, 2009/58(46);1296-1299
About Dr. Tan
Dr. Tan graduated from the National University of Singapore in 2001. His residency was in the two largest public hospitals in Singapore; Tan Tock Seng Hospital and Singapore General Hospital.