How Antibody Testing Is Helping Fight COVID-19

How Antibody Testing Is Helping Fight COVID-19

  • This page was last updated at June 17, 2024.

Since the impact of COVID-19 hit a global scale, the medical world has made numerous attempts to deal with the disease. Currently, thorough research on the disease is still ongoing and antibody testing is starting to take place.

The studies of the human ability to develop these antibodies will help medical practitioners understand the nature of the disease. Hopefully, these broad steps will provide a permanent solution to the disease. 

COVID-19 Tests

COVID-19 can be identified using two tests. These are the virology test; and the antibody test. 

The Virology Test

The virology test is also called the "Polymerase chain reaction (PCR)" or the molecular test. It traces the genetic matter left by SARS- CoV-2, the virus that causes COVID-19.

The virology test is the appropriate test to check whether the virus infects an individual. The test is done by taking samples from swabs from the mouth, throat, and nose of the individual. The FDA has authorized various companies to provide these tests. Their services differ on the method of collection of samples and the testing process. 

The Antibody Test

The second test, the antibody test, is also called the serological test. It is done by taking blood samples from individuals. The test seeks to establish whether an individual was affected by the virus in the past.

When the immune system of an infected person fights the SARS-CoV-2 virus, it releases antibodies. It is these antibodies that are detected by the test to indicate a past infection. The medical practitioners can also use the antibodies to look at the immunity of the tested individual. An individual with a weak immunity will not produce these antibodies well. 

It should also be noted that the antibody test must be done when the individual has been infected for over three weeks. Before this time, the antibodies might not show in the individual's sample. Therefore, the test might give a negative result where, in reality, the individual is infected with the virus. Interestingly, asymptomatic individuals will also produce these antibodies.

Immunity and the Antibody Test 

The Center for Disease Control (CDC) said that it is not clear whether having these antibodies can protect an individual from having COVID-19 again. However, theoretically, people who were asymptomatic for the disease are deemed to have successfully overcome the virus. This is how the immune system operates with other infections. Research on COVID-19 is still undergoing. Therefore, until a conclusion is found, it remains uncertain whether the antibodies' presence means the individual is immune from the disease. 

Scientists are researching how long the immunity evidenced by the antibody testing lasts. A research done on non- human primates revealed that they could develop an immunity 28 days after their infection with the SARS-CoV-2 virus. However, it is not clear how long this immunity lasts. In other research, scientists compared the COVID-19 disease to SARS. SARS-CoV-2 and the virus that causes the SARS disease are similar. Therefore, a study of antibody activity in SARS patients would help understand the immunity of individuals with SARS-CoV-2 antibodies. 

Countries around the world can use the antibody tests to check how many individuals got infected with the SARS-CoV-2 virus and recovered. Because of this, the demand for antibody test kits has been on the rise. Currently, in the United States, for example, it is estimated that there are over 200 companies that produce SARS-CoV-2 antibody testing kits. 

Some FDA Approved Testing Kits

Initially, the FDA had strict guidelines for the distribution of the antibody test kits. It gave direct authorization to 12 companies to provide the antibody testing kits. However, with the rapidly rising numbers, the FDA came up with updated testing guidelines. These guidelines set a policy to ensure the mass distribution of the serology testing kits through the Emergency User Authorization (EUA). 

Under the EUA, the companies providing the testing kits may not be subjected to the strict authorization from the FDA. Currently, over 200 companies distribute testing kits all over the United States. 

The companies that get authorization to distribute the testing kits differ in the collection methods and testing processes. 


As of May 25, 2020, Labcorp began distributing antibody testing kits at a national level throughout the United States. The testing kits are not available commercially. Users can only access them via their doctors. The company also provides a telehealth service, where individuals can request for the tests through the company's website, Sometimes, the users may fill in online forms to check whether they need the testing kits.

The company also has several collecting points for the testing kits. Currently, there are almost 2,000 such centers all around the United States. 

For pricing, Labcorp bills according to the guidelines provided by the Centers for Medicare and Medicaid Services (CMS). To settle the cost, the company sends the users' bills to the users' insurance company. In situations where the users do not have insurance coverage, the bills are sent to the responsible government program.


On May 11, 2020, Abbot received an Emergency User Authorization to distribute its COVID-19 antibody testing kits. The company projects that by June this year, the Alinity usage will hit the 60 million mark. The EUA allows for the companies to distribute different systems of testing kits. For example, Abbott had initially been producing the antibody testing kits under the ARCHITECT system.

According to the company, the Alinity system is more efficient in conducting the serology tests. It performs more tests on a relatively small space. It also seeks to reduce the risk of human error. The system is currently in use in hospitals, research facilities, and laboratories across the United States. 

Clinical tests done on the Alinity system revealed that scored a high percentage, above 95%, in both its ability to exclude both false positives and negatives when in use. It follows; through Alinity, Abbott aims to provide quality results. 


EverlyWell is widely known for its COVID-19 home testing kit. The users order the kits online and mail the results back to certified labs within 48 hours. These kits are only available for the virology tests.

To access the kits, they must first fill an online form that gets reviewed by online healthcare providers. After the review, it is determined whether one is fit to undergo the testing. Results for the tests are provided online. Individuals who test positive can follow steps provided on the company's website. The test is done by a nasal swab done by the users at their homes. 

Guidelines on Testing

The guideline that provides for EUA makes companies have their products in the market faster than usual. Besides, after notifying the FDA for their intention to seek EUA, the companies can start distributing their test kits. The FDA requires that the companies provide their EUA requests within ten official days after submitting their notification. 

The relaxing of strict authorization has brought issues. Some companies take advantage of the lack of it to produce sub-standard testing kits. To deal with this, FDA has partnered with the CDC, the Biomedical Advanced Research and Development Authority (BARDA), and the National Institute of Health (NIH) to assess and check the performance of antibody tests.

Since the FDA does not approve the results obtained by these testing kits, the companies carry their validations themselves. The guidelines provided by the FDA require that the tests are taken by the commercial distributors of the testing kits to be validated. The reason for this is that a false test can harm public health.

The FDA also encourages the companies to use the templates it has provided for conducting serological tests. It also advices these companies to seek recommendations from them when the companies intend to use their templates instead. 

FDA requires the companies that manufacture the testing kits to use precise language to help users understand the results. For example, they should clearly state that the antibody test does not show one is infected with COVID-19. 

When released into the market, high priority testing should be done. Priority should be given to people who have been exposed to the SARS-CoV-2 virus, for example, doctors, nurses, and other individuals providing essential services.

The antibody test can be used by countries to end lockdowns. They can also be used to qualify those who have immunity to resume their work. It has been suggested that for this to work effectively, virology tests should follow the antibody tests. This move will help the individuals to be sure they are entirely free of SARS-CoV-2.