- Covid-19 disproportionately affects older adults and males, causing severe disease and death.
- Scientists have recently discovered many clues to explain why this happens.
- In a new study, researchers say it may have to do with our antibodies and their blocking of interferons in patients who have immune diseases.
One of the lingering questions of the Covid-19 pandemic is why the disease, caused by SARS-CoV-2, appears to hit older people harder than young adults and children.
A new study suggests that one of the answers may have to do with our antibodies.
"We found that persons with serious Covid-19 disease have antibodies that are blocking so-called interferons, which are an important part of the body's defence mechanism," Professor Eystein Husebye from the Department of Clinical Science at the University of Bergen (UiB) in Norway said in a news release issued by the university.
Husebye conducted the study together with his French colleagues and their findings were published in the journal Science.
The discovery may allow for possible treatment
He has had plenty of experience with patients who have autoimmune polyglandular syndrome (APS1) – a serious, but rare, immune disease.
Patients who have APS1 have a high concentration of antibodies against interferons. Interferons are proteins that are produced by the body's cells and they act as a defensive response to viruses.
Huseybe and his team found that if patients who have APS1 become infected with Covid-19, their bodies work against their own immune systems.
This response, the authors wrote, was also seen in patients who had milder immune diseases.
"It is relatively easy to see if young people with Covid-19 have these antibodies in their blood. If so, it might be possible to supply them with extra interferons as treatment," Husebye explained.
More clues to explain why the disease hits men harder
According to the researchers, their findings help clarify other mysterious findings relating to Covid-19.
"Deaths and severe Covid-19 are more frequent among men than women. Our study has shown that men have more of these antibodies," Husebye said.
In addition to antibodies, other research on why the disease appears to affect the sexes differently points to evidence of differing levels of viral load and other immune responses.
However, in spite of the convenience of blood tests that can discover antibodies against interferons, Husebye cautions against mass screening of healthy people.
This is because most people living with APS1 are commonly diagnosed in their childhood, and most people with immune failure have already been diagnosed.
"Immune failure is just a piece in the puzzle when it comes to understanding why young people may die of Covid-19. Old people generally die of more complex causes," he commented.