November 13, 2020 -- After catching the common cold, some people may develop antibodies that also protect them from COVID-19, according to a new study published in the journal Science.
Children, in particular, seem to benefit from these antibodies.
“Children are much more likely to have these cross-reactive antibodies than adults,” Kevin Ng, a PhD candidate, the lead study author and a researcher at the University College London’s Francis Crick Institute, said in a statement.
Several different strains of coronaviruses cause the common cold, so it makes sense that antibodies from one strain might help the body to recognize the coronavirus that causes COVID-19, the researchers concluded.
The research team discovered the correlation while developing a new, more sensitive test to screen for COVID-19 antibodies in people who have already been infected. While checking their tests, the researchers found that some people already had antibody proteins that reacted to COVID-19 — even though they hadn’t contracted it yet.
In a more in-depth analysis of 300 blood samples collected before the pandemic from 2011-2018, they found that nearly all of the people had common cold antibodies. In addition, about 5% of the adult samples had antibodies that could “recognize” COVID-19, and 7% had recently come down with a cold with similar antibodies.
Notably, nearly half of the children between ages 6-16 had these antibodies that would recognize COVID-19.
“More research is needed to understand why this is, but it could be down to children being more regularly exposed to other coronaviruses” such as the common cold, Ng said.
The common cold antibodies could also explain why children are less likely to develop severe COVID-19. However, the researchers can’t say for sure whether these antibodies prevent COVID-19, reduce virus transmission or reduce the severity of the disease.
The study raises several questions, the researchers said. Future studies should explore how the immunity to one coronavirus affects another coronavirus and whether the level of immunity is related to other factors such as age.
“This is exciting, as understanding the basis for this activity could lead to vaccines that work against a range of coronaviruses, including the common cold strains, as well as SARS-CoV-2 and any future pandemic strains,” George Kassiotis, the senior study author, said in the statement.
However, people who have recently had a cold should still be careful about contracting COVID-19, he added. With more than 52 million COVID-19 cases worldwide, many people don’t appear to have these pre-existing antibodies that can fight off the virus.
“It is not the case that people who have recently had a cold should think they are immune to COVID-19,” he added.