A new study indicates that antibodies developed by a person who catches an ordinary cold may also provide some protection against Covid-19.
The small-scale study, published in the scientific journal Nature Communications, examines 52 people who live in the same house with someone who has recently contracted Covid.
It seems that those who develop antibodies that strengthen immunity after the cold are more difficult to catch Covid.
Experts especially stress that no one should rely on such immunity alone, and that the vaccine is critical.
But they think the findings of this research still offer useful information for understanding how the human immune system fights the virus.
Covid-19 disease is caused by one type of coronavirus, and there are colds caused by other types of coronaviruses.
So the scientists conducted this research to examine whether immunization against some types of coronavirus provides protection against others.
However, they remind us that it would be wrong to think that someone who has a cold recently is automatically protected against Covid-19, because not all colds are caused by coronavirus types.
The scientific team at Imperial College in London aimed to investigate why some people exposed to the coronavirus get Covid while others do not.
‘New vaccine approach’
In their research, they focused on T cells, which form a very vital part of the human body’s immune system.
Some of these T cells function to kill any cell infected with a certain threat, such as the cold virus.
After the cold has passed, these T cells remain in the body like a kind of memory bank and are ready to take action the next time the virus is encountered.
In September 2020, the research team followed up with 52 people who had not yet been vaccinated but were living with someone who had just recently had COVID-19.
Half of the group got Covid from the person they lived with within 28 days, the other half did not contract the disease.
It was noted that one-third of those who did not get the disease had a high amount of T cells that carry a certain memory in their blood.
These T cells were likely produced when the body encountered another virus that was similar to the coronavirus that causes Covid-19, but that caused the common cold.
The researchers acknowledge that many other factors, such as how airy the homes are, may have contributed to the subjects’ absence of the disease.
University of Reading’s Dr. Simon Clarke said that although this is a small-scale study, it is useful in understanding how the immune system fights the virus and may be useful in developing vaccines in the future.
Dr Clarke said: “These data should not lead to different interpretations. It is unlikely that anyone who has contracted the disease, suffered severe or died from a coronavirus-related cold, and it would be a big mistake to think that someone who has a cold soon will not catch Covid-19. “Only 10-15 percent are due to coronavirus,” he said.
Professor Ajit Lalvani, who reported on the Imperial research, also agrees that the most important protection is vaccination.
“Learning what the body is doing right can be helpful for new vaccine designs,” he says.
The vaccines currently used specifically target protein projections on the outer surface of the virus. But these protrusions change a little more with each new variant of the virus.
But the T cells produced by the body target the proteins in the virus and they do not change from variant to variant. According to Professor Lalvani, this means that vaccines that can replicate the function of T cells could provide more comprehensive and long-term protection against Covid.