FACT CHECK Common cold doesn’t yield positive COVID-19 tests
As coronavirus case counts surge across the country, social media users claim that the recent increase in cases is the result of common colds producing positive test results.
Users on Instagram and Facebook are sharing a screenshot from the Centers for Disease Control and Prevention’s website.
“(Sharing) let this sink in... the COMMON COLD can produce a positive COVID test!! do the increase of numbers really mean ANYTHING at this point??” a June 28 Facebook post reads. “So we are shutting down businesses, mandating masks & causing mass hysteria of this ‘second wave’ for THIS?!! 99.99997% survival rate!!”
A similar post was shared on Instagram of a screenshot of an article headlined, “Now Even the COMMON COLD Is Being Counted As A Positive COVID-19 Result, CDC Says.”
Though the posts link to the CDC’s website and the text in the screenshot is real, the information is being misinterpreted.
“A positive test result shows you may have antibodies from an infection with the virus that causes COVID-19. However, there is a chance a positive result means that you have antibodies from an infection with a virus from the same family of viruses (called coronaviruses), such as the one that causes the common cold.” Centers for Disease Control and Prevention website, in regards to antibody testing, not viral diagnostic testing, a distinction ignored by social media posts misrepresenting the quote to claim the common cold can cause a positive test result
COVID-19 viral test confused with antibodies test
The information shared online about common colds relates to antibody testing, not coronavirus tests.
“A positive test result shows you may have antibodies from an infection with the virus that causes COVID-19,” the CDC states on its website, on a page dedicated to past infections. “However, there is a chance a positive result means that you have antibodies from an infection with a virus from the same family of viruses (called coronaviruses), such as the one that causes the common cold.”
On the website, it is noted that “except
in instances in which viral testing is delayed, antibody tests should not be used to diagnose a current COVID-19 infection.”
According to the CDC, an antibody test may not show if a person has a current COVID-19 infection because it can take from one to three weeks for the body to develop antibodies. To test for a current infection, a viral test is needed.
How do tests differ?
Antibodies are Y-shaped proteins produced by white blood cells to stop a virus from intruding. Tests look for immunoglobulin M (IgM) and immunoglobulin G (IgG) in the blood, USA TODAY reported.
Antibodies are measured by testing a person’s blood, according to the Food and Drug Administration.
Dr. Raed Dweik, chairman of the Respiratory Institute at the Cleveland Clinic, told USA TODAY that some of the antibody tests he has seen aren’t accurate enough to determine if someone is immune to COVID-19. That’s because antibodies for the coronavirus appear very similar to other coronavirus antibodies that cause illnesses, such as the common cold.
These tests could incorrectly indicate the presence of antibodies that are for the novel coronavirus, creating a false-positive test result.
Dweik said it will take more time to develop a test that can accurately detect the right antibodies.
Viral tests check samples from the respiratory system by swabbing the inside of the nose to detect SARSCoV-2, the virus that causes COVID-19, according to the CDC.
There are two types of viral diagnostic tests – molecular (RT-PCR) and antigen tests – that can show an active coronavirus infection, according to the FDA.
“Antibody tests should not be used to diagnose an active coronavirus infection,” the FDA’s site reads. “At this time researchers do not know if the presence of antibodies means that you are immune to the coronavirus in the future.”
Our ruling: False
The posts being shared misinterpret information, confusing antibody testing for viral testing. Our fact check work is supported in part by a grant from Facebook.