FLEMINGTON, NJ - Everyone is talking about tests for COVID-19.  Here is a brief explanation of the tests and what they mean.

There are two general types of COVID-19 tests: PCR tests and antibody tests: 

COVID-19 Testing or PCR Tests

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These tests are used to diagnose someone who is sick.  PCR stands for “polymerase chain reaction”.   It identifies the genetic material of the virus and is usually done with a swab rubbed in the back of the nose, where the virus is found.  Some research centers have developed versions that use saliva instead of the nose swab; the saliva test is limited to the research center where it was developed, so it is not available at Hunterdon Medical Center.  

Up to 30% of people who have symptoms have a negative PCR test.    This could mean that there is another reason for the symptoms, but it could also mean that the swab didn’t catch the virus, or that the test was not accurate and the person did have COVID-19.    

Because the materials needed to do the test are in limited supply, there is guidance about which patients to test.  Higher priority is given to hospitalized patients and to those who are elderly or have chronic diseases.  Healthcare workers and first responders are also a high priority for testing in order to keep a workforce ready to take care of our citizens. 

Results for most of these tests take a few days to come back.  There are some tests that offer results in an hour; since these are in limited supply they are reserved for patients in the hospital.

Antibody Tests

These are blood tests used to tell if someone had COVID-19 and recovered.  They are not used to diagnose someone who is sick now.  The test looks for proteins in the blood called “antibodies” or “immunoglobulins” known as “IgG”.

More than 90 companies are selling COVID-19 antibody tests, but not all give reliable results.  It is very important to understand the accuracy of the test before deciding whether to do it.  Tests can be falsely positive or falsely negative.  At Hunterdon Medical Center, we only offer tests done at labs we know and trust, but the meaning of the results is still being investigated.  Ask your doctor for help understanding how the test can help you, and how to interpret the results.

High levels of IgG for other viruses can mean that a person had the virus and is now immune.  We believe that persons who test positive for COVID IgG were infected, but we do not know whether people can get COVID-19 more than once.

California and other states have begun to test their population to try to understand how many people have been exposed to coronavirus.  New Jersey is considering implementing this in the future.

Convalescent Plasma Donation

Convalescent Plasma has been shown to help people sickened by COVID-19. For people who have been diagnosed with COVID-19 and have recovered from the virus, you can help save a life of someone else with COVID-19 by donating convalescent plasma.
To participate you must meet the following criteria:
● You must be free of symptoms due to COVID-19 for at least 28 days.
● You must be in good health and eligible to be a volunteer community blood donor.
● You must be able to show that you were diagnosed with COVID-19. This can be done by having your doctor complete the Attestation Form available via this link: https://www.giveapint.org/covid-plasma-form/
● If you have had a pregnancy, tissue transplant or transfusion you must be negative for HLA antibodies. If your HLA antibody status is unknown the blood center can test you.

If you are interested in being a donor and meet the donor criteria listed below, please contact the Miller-Keystone Blood Bank at (610) 691-5850, extension 1279, and tell them that you are interested in helping Hunterdon Medical Center patients with COVID-19 by making a convalescent plasma donation.

The same precautions are necessary for everyone, whether tested or not. Everyone should continue social distancing, masking, staying home when sick, hand washing and disinfecting high touch surfaces.

For more information, visit www.hunterdonhealthcare.org.