Globally, men account for about 60% of deaths from Covid-19, according to the new study published in the journal Nature, and it examined whether differences in immune responses could explain the cause.
Women have a stronger immune response
“What we found is that men and women actually develop different types of immune responses to Covid-19 virus, and these differences may underlie the increased susceptibility to disease in men,” said lead author Akiko Iwasaki, a professor at Yale University.
Researchers collected nasal samples, saliva and blood from uninfected people and patients who had been treated at Yale New Haven Hospital in the United States, and then monitored the patients to look for their immune responses.
The researchers found that the women had a more robust immune response that included T lymphocytes, a type of white blood cell that can recognize and eliminate viruses, and it was also among older women.
In contrast, older men had weaker T cell activity – the older they got, the weaker the response, and in general, men also produced more cytokines, which are inflammatory proteins that are another part of the body’s natural immune defense.
However, severe cases of Covid-19 have been linked to what is known as a “cytokine storm”, when the immune system goes into overdrive, which is harmful and potentially fatal.
The study found that men who showed high concentrations early were more likely to develop the disease, while women who also showed high levels of cytokine seemed to fare worse. According to the authors, this could mean that men and women need different treatments.
For men, for example, “we should boost their T-cell responses with vaccines,” Iwasaki said, while women could be given a treatment to dampen the cytokine response.