COVID-19 Diagnostic and Antibody Tests Explained

COVID-19 is uncharted territory. The 2009 H1N1 Pandemic, often referred to as swine flu, served as an ominous precursor to 2020’s Coronavirus, which has already greatly surpassed H1N1’s mortality rate.

Most employers today have not experienced a pandemic like COVID-19 in their adult life. Due to this, they may be seeking out advice on topics they have not previously researched.

Finding a cure has been on everyone’s minds throughout this crisis, particularly those working with customers face-to-face. Staying safe is important, and the workplace has had to shift drastically throughout many companies to keep clients and employees safe. Without yet a cure, social distancing and testing have been two ways to combat spreading of the virus. Testing specifically may determine who is or is not allowed to come to work.

COVID-19 tests have been authorized by the FDA under an Emergency Use Authorization. EUAs occur when major public health crises call for quick action. A product distributed under an EUA may obtain less successful results than a product that has been approved. The United States’ Secretary of Health and Human Services declared a public health emergency on January 31st, 2020, and President Trump declared a national emergency on March 30th, 2020. This declaration allocated up to 50 billion dollars’ worth of federal funds towards various methods of fighting Coronavirus.

There are two kinds of COVID-19 tests: diagnostic tests, which determine if someone is positive currently, and antibody tests, which determine if an individual has antibodies in their system, indicating that they had the virus in the past. Given the newness of both tests, it may be difficult to initially understand that they are checking for separate things. If one does not yet understand the difference, it could lead to them sending home employees who could actually be working safely.

When an individual tests positive for a diagnostic test, this means that they have the virus now. There are two types of diagnostic testing, a polymerase chain reaction test (PCR), and an antigen test. Both the PCR and antigen test are typically performed by a healthcare provider taking a nasal or throat swab. Note that while a positive test using either diagnostic test indicates an active COVID-19 infection, a negative antigen test does not rule out COVID-19 and it is recommended that if COVID-19 is still suspected, a PCR test should be given.

The incubation period for Coronavirus may range anywhere from two days to two weeks, meaning that it is possible for an infected individual to be symptom-free for fourteen days following an exposure. While most people with symptomatic COVID-19 will show symptoms around five to six days into infection, it is essential that someone who knows they have been exposed must wait two weeks before returning to work or receives a negative diagnostic result. There are different kinds of diagnostic tests which receive results between a few minutes and multiple days.

Antibody tests determine a post-infection diagnosis to Coronavirus. For an antibody, a blood sample is usually taken and sent to a lab for testing. These tests work largely toward researching the virus — a positive antibody test can offer very useful information including tracking community spread, determining who is able to form antibodies, as well as potential treatments for individuals who are dealing with the most severe forms of COVID-19. A positive antibody test does not mean an individual has Coronavirus currently.

Also, as to what a positive test means as far as a person having immunity or resistance to COVID-19, the CDC states that “Having antibodies to the virus that causes COVID-19 might provide protection from getting infected with the virus again. If it does, we do not know how much protection the antibodies might provide or how long this protection might last.”     

For employees who have tested positive initially, two negative test results, with samples collected a minimum of 24 hours apart, should be obtained prior to an employee’s return to work as individuals may still have the virus even after symptoms go away, or, may be completely asymptomatic. The safety of coworkers and clients should be top priority of a company leader as the nation continues to endure the changes that come with this pandemic.

Physicians Health Centers has programs designed to help local employers with both PCR diagnostic testing and antibody testing. Please email if you would like to learn more about our programs or visit our website at