Understanding COVID-19 PCR Testing

Author: Doreen Gao

Aug. 11, 2025

Understanding COVID-19 PCR Testing

Primers attach to the end of these strands. Primers are small pieces of DNA designed to only connect to a genetic sequence that is specific to the viral DNA, ensuring only viral DNA can be duplicated (right). After the primers attach, new complementary strands of DNA extend along the template strand. As this occurs, fluorescent dyes attach to the DNA, providing a marker of successful duplication. At the end of the process, two identical copies of viral DNA are created. The cycle is then repeated 20-30 times to create hundreds of DNA copies corresponding to the SARS-CoV-2 viral RNA.

Goto TSKT to know more.

What do results mean for a COVID-19 PCR test?

A positive result happens when the SARS-CoV-2 primers match the DNA in the sample and the sequence is amplified, creating millions of copies. This means the sample is from an infected individual. The primers only amplify genetic material from the virus, so it is unlikely a sample will be positive if viral RNA is not present. If it does, it is called a false positive.

For more information, please visit PCR Kits.

A negative result happens when the SARS-CoV-2 primers do not match the genetic material in the sample and there is no amplification. This means the sample did not contain any virus.

A false negative result happens when a person is infected, but there is not enough viral genetic material in the sample for the PCR test to detect it. This can happen early after a person is exposed. Overall, false negative results are much more likely than false positive results.

If you are looking for more details, kindly visit qPCR Kits.

22

0

Comments

Please Join Us to post.

0/2000

All Comments ( 0 )

Guest Posts

If you are interested in sending in a Guest Blogger Submission,welcome to write for us!

Your Name: (required)

Your Email: (required)

Subject:

Your Message: (required)