There has been a lot of talk about COVID-19 antibody testing, and even more questions. When can I get it? Where can I get it? Is it even accurate? What does it mean if I test positive for antibodies? It’s a complicated topic, but we’ll try and make some sense of it for you.
First, let’s start with the basics:
What are antibodies?
Antibodies are proteins created by your body to fight off pathogens, like bacteria and viruses. Your immune system makes specific antibodies to each particular pathogen you encounter and successfully fight off. Your body also makes antibodies when you receive vaccines, so you can get the same immune benefit of having an illness without having to go through the discomfort of actually having the illness. These antibodies remain in your blood after you’ve fought off the infection, and antibody tests, also called serology (fancy way of saying blood) tests, can detect them.
How long do antibodies last?
This completely depends on what the antibody is designed to fight. Some antibodies, like those against chicken pox and tetanus, potentially last decades or even a lifetime. Others, like those that fight against the common cold, have shorter lives, usually just a few months.
The common cold is often caused by coronaviruses. If antibodies against the novel coronavirus behave in the same way, immunity to COVID-19 may not last very long. It’s possible that the antibodies will last for years, or it’s possible that people will be susceptible to reinfection much quicker than that. Once a vaccine is produced, you might need just one immunization in your lifetime or you may need a yearly vaccination in order to stay protected. It’s just too early to tell.
Can an antibody test tell me if I have COVID-19?
No, it can take 1-3 weeks – or longer for some people – after infection for your body to start making antibodies, so a serology test can only tell you if you may have had the virus in the past and now have antibodies to it. If you want to know if you have an active infection, you’ll need a viral test that looks for virus DNA. These tests are generally a nasal swab test or a nasopharyngeal swab test. You can request a test from your health care provider or go to the drive-thru testing site at Skagit Valley College, Monday-Friday, 9am-4pm.
Many people have wondered if the drive-thru testing site will start offering antibody testing. At this time, there is no plan to do so. The main goal of the drive-thru testing site is to catch active cases and stop the virus from spreading.
Are COVID-19 antibody tests accurate?
Well, that depends. Some tests are more accurate than others. There are a lot of tests floating around that are completely bogus. Your best bet is to contact your health care provider and get the test from them. But even with the most accurate serology test, there is a chance that you’ll receive a false positive, meaning the test says you have antibodies but you really don’t.
Even if you do have antibodies present in your blood, indicating you’ve had the infection, we do not know how long those antibodies will last. You might be protected this week, and vulnerable to reinfection next week. Or you might be protected for months or years. Nobody knows for sure!
For both of these reasons, it’s important that you don’t view a positive antibody test as a free pass to do whatever you want. You still need to follow social distancing guidelines, wear a mask in public, try your very hardest not to touch your face or mask, and wash your hands or use hand sanitizer often. We know it’s not what you want to hear, but it’s the truth, and we want you to know the facts so you can keep yourself safe and healthy.
If you want more information about serology testing, the CDC and FDA have plenty of research available. Please note that not all tests that are available have been approved by – or even applied for approval from – the FDA, so if you want to take an antibody test, talk to your healthcare provider so you can ensure the test you take (and spend your money one) is FDA approved.
So, why bother getting an antibody test at all?
Skagit County has tested thousands of people for active COVID-19 infections, but we know that many people who had COVID-19 were never tested. It’s possible that they had mild or completely asymptomatic cases of COVID-19 and never knew they were sick, or caught the virus before tests were widely available. They may have never been formally diagnosed with COVID-19 but still have antibodies present in their blood.
Antibody tests can be used to get a general sense of how widespread COVID-19 has been in the community. While it might not be a good idea to base your individual actions on your antibody test result, experts can use the data of a population to form their health recommendations going forward. You can learn more about the research being done here. Researchers can also use the data to figure out what exactly it means to have antibodies in your system: Are you immune to reinfection? For how long?
Additionally, there is ongoing research into whether “convalescent plasma” – a specific part of the blood – from those who have recovered from COVID-19 can be used as a treatment for those who are seriously ill from COVID-19. If you have antibodies in your blood, you could help scientists develop a treatment that potentially saves lives. You can find out more information about donating your plasma and where you can do so here. There are locations in Bellingham and Everett, and several others in King and Pierce counties.
Right now, there are a lot of unknowns about antibody testing and what a positive test result means for your future health. This is a new virus, and we’re still learning a lot about it. As researchers find out more about COVID-19, Skagit County Public Health will share this information with you. Your health is our priority.