High levels of protective immune cells that fight common colds, a specific type of white blood cell that plays a critical role in the immune system, can also make people protective to contract covid.
However, experts warn that no one should rely only on this defense, and immunizations remain critical.
This is the result of a small-scale study, published in Nature, which included 52 people who shared an apartment with someone who had recently contracted Covid-19.
Will you offer us a hand? Every gift, regardless of size, fuels our future.
Your critical contribution enables us to maintain our independence from shareholders or wealthy owners, allowing us to keep up reporting without bias. It means we can continue to make Jewish Business News available to everyone.
You can support us for as little as $1 via PayPal at firstname.lastname@example.org.
According to the study, individuals who formed a “memory bank” of certain immune cells following a cold – presumably to aid in preventing subsequent attacks – looked to be less likely to contract Covid.
Because Covid-19 is caused by a type of coronavirus and some colds are caused by other coronaviruses, experts wondered if immunity to one could assist with the other.
The researchers advise that it would be a “grave error” to believe that anyone who had a cold recently was automatically protected against Covid-19 – as not all colds are caused by coronaviruses.
The Imperial College London team hoped to better understand why some patients get Covid following viral exposure while others do not.
‘A novel vaccination strategy’
They concentrated their research on a critical component of the immune system – T cells.
Certain T-cells eliminate any cells infected with a specific hazard, such as a cold virus.
Additionally, once the cold has passed, some T-cells stay in the body as a memory bank, ready to create a defense against the virus upon its next contact.
In September 2020, researchers evaluated 52 individuals who had not been vaccinated but lived in close proximity to those who had recently tested positive for Covid-19.
During the 28-day study period, half of the group received Covid and half did not.
A third of those who were not infected with Covid had elevated levels of particular memory T cells in their blood.
These were most likely formed after the body was infected with another closely similar human coronavirus – most typically, a common cold, they add.
The researchers acknowledge that additional variables – like ventilation and the infectiousness of their household contact – could have an effect on whether people contracted the illness.
Dr. Simon Clarke of the University of Reading said that despite the study’s small size, it contributed to our understanding of how our immune system fights the virus and may benefit in the development of future vaccines.
“These facts should not be over-interpreted,” he added. It seems improbable that everyone who has died or has had a more serious infection has never experienced a coronavirus-caused cold.
“And it would be a major error to believe that everybody who has just had a cold is immune to Covid-19, as coronaviruses account for only around 15% of colds.”
Professor Ajit Lalvani, the study’s lead author, concurred that immunizations were critical for protection.
“Learning from what the body accomplishes correctly may help inform the design of new vaccinations,” he added.
Current vaccines target spike proteins on the virus’s outer surface, but these spike proteins can change in response to novel strains.
However, because the body’s T cells target internal viral proteins that do not vary significantly between variants, vaccinations that more closely mimic the action of T cells could provide broader, longer-lasting protection against Covid, he said.