“Is it a cold or is it COVID?” This question is on the minds of many as kids return to schools and the Omicron variant, with less severe symptoms, continues to circulate. In some milder cases, only testing will determine if your stuffy nose and scratchy throat are the results of the common cold or the novel coronavirus. However, if you do catch a cold this winter, research suggests the body’s natural defenses against a common cold may offer some protection from future COVID-19 infection.
According to a recent BBC news report, a small study published in Nature Communications found that participants who developed specific immune cells after having a cold appeared to be less likely to get COVID. But researchers stress that having been infected by the common cold is not a prevention alternative to vaccines, but may offer some additional protection.
What is interesting to scientists is the link between some colds caused by other coronaviruses and COVID-19, and if immunity against one might provide some protection from the other. But it’s important to remember that not all common colds are caused by coronaviruses and so it would be a mistake to believe having contracted a cold is a guarantee of protection from COVID-19. Coronaviruses, which have been traced back as far as 8000 BCE, only account for about 10 to 15 percent of colds.
Researchers did find that a third of the study group who tested positive for COVID-19 in September of 2020 but did not develop an illness, were found to have high levels of specific memory T-cells in their blood. Some of these T-cells kill any cell infected by a specific threat, like the cold virus. Researchers concluded that the group of people who did not become ill with COVID-19 were likely to have created T-cells in their blood when they were infected with another closely-related coronavirus, such as the common cold.
Other factors including household ventilation and contact with other infected people would also influence whether or not study participants developed a COVID-19 illness. The study, although small, adds to the body of knowledge about how our immune system fights the virus and could be useful in developing future vaccines. Current vaccines target spike proteins outside of the virus, but these proteins can change with new variants. T-cells, however, target internal virus proteins which do not change as much between variants. Developing second-generation vaccines that use the work of T-cells could provide more comprehensive and longer-lasting protection against the novel coronavirus.