PCR vs. Rapid Test for COVID-19: Pros and Cons

More than 650 million COVID-19 tests have been done in the United States since early 2020, and nearly 50 million of those tests identified the COVID-19 virus responsible for a global pandemic.

Testing rates decreased for a time once vaccines became available and the numbers of new cases started to decline. However, new variants and a desire to return to a semblance of normal life have increased the demand for tests again.

There are more options for testing now than there were at the start of the pandemic. Lab testing is still available, but new types of at-home tests have made testing easier. Not every test is created equal, though, and there are pros and cons to each type of COVID-19 test.

This article will review the different COVID-19 tests and the benefits and drawbacks of each.

PCR Test

Polymer chain reaction (PCR) tests are typically performed in a laboratory or healthcare setting. Using a swab, you or a technician will collect a sample of cells from your nose, mouth, or throat.

After collection, the samples are treated with an enzyme solution and examined under extreme amplification (copied multiple times). The technique allows test centers to identify the exact genetic materials in the sample, including the identity of a specific virus. The test can also differentiate between different variants—or strains—of a virus.

Since the tests examine microscopic bits of a virus's genetic material, they are highly reliable—often close to 100%. The downfall to the process is the time that it takes and the fact that lab analysis is required to get results.

PCR tests can be performed quickly when there is an urgent need, but they take at least a few hours to produce results. If you are not close to the lab that is doing your test, it can add extra time. Increased demand and the number of tests a particular lab is responsible for can also delay your results. The hours that the test takes to complete can turn into days when distance and demand are factored in.

In mid-2020, the Food and Drug Administration (FDA) began approving at-home PCR test kits that allow you to collect a sample at home and then send it to a lab for testing.

There are also a few options for nucleic acid amplification tests that can be used at outpatient clinics and can provide a result in about 20 minutes. These tests look for nucleic acid from the virus instead of antigen.

Rapid Test

Rapid antigen testing looks for pieces of the viral proteins from the SARS-CoV-2 virus (antigens) that causes COVID-19 rather than genetic material (nucleic acid from the virus). These tests are quick and are often used to detect other viruses that cause illnesses like the flu, respiratory syncytial virus (RSV), and sexually transmitted infections (STIs).

The FDA has approved several rapid antigen tests for COVID-19 because they offer a more simple and accessible option for testing. They can also produce results in under an hour.

Which Test Should You Use?

There is no right or wrong answer when it comes to which COVID-19 test is best. There is a time and place for each type, and which one you choose will depend on your situation and symptoms.

For example, if you are sick and wondering whether your symptoms could be caused by COVID-19, a rapid test can give you that answer quickly. That's helpful because it would allow you to isolate yourself from other people to help reduce the spread of the virus.

However, if you do not have symptoms or you're simply taking a test before an event to make sure that you're not sick, a rapid antigen test may not be able to give you the most accurate result.

People who are symptomatic who need testing before a medical procedure, people who are testing because they were exposed to someone with COVID-19, or people who remain sick despite numerous negative rapid tests are the best candidates for PCR testing. While this type of testing takes longer and is more expensive than rapid tests, it can provide you with the most accurate result.

Summary

Both PCR and rapid antigen tests offer reliable options for testing if you have symptoms that could be from COVID-19. Rapid antigen tests can be more effective if you need to do repeated (serial) testing.

A Word From Verywell

The COVID-19 test that you choose will depend on how you are feeling, why you are taking a test, and how vulnerable the people around you are to getting sick. If you need immediate results, a rapid antigen test might be the best option. However, if you need the most accurate test, or you are still sick and want to validate your rapid test result, PCR is the better choice.

If you have questions about COVID-19 testing, symptoms, or treatment, talk to your doctor or another trusted healthcare provider.

The information in this article is current as of the date listed, which means newer information may be available when you read this. For the most recent updates on COVID-19, visit our coronavirus news page.