Women Have Stronger Immune Response to COVID Than Men, Study Says

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Since the early days of the coronavirus pandemic, it's been known that older men have a higher risk of getting very sick and dying than older women.

A study published Wednesday in the journal Nature says that may be because women's bodies produce a stronger immune response than men's bodies.

Even into old age, women produce more T cells, which can stop the virus from spreading, the study said.

"Female patients mounted significantly more robust T cell activation than male patients during SARS-CoV-2 infection, which was sustained in old age," Nature said. "Importantly, we found that a poor T cell response negatively correlated with patients' age and was associated with worse disease outcome in male patients, but not in female patients."

"When (men) age, they lose their ability to stimulate T cells," Dr. Akiko Iwasaki, an immunologist at Yale University who led the work, told The New York Times. "If you look at the ones that really failed to make T cells, they were the ones who did worse with disease."

The researchers studied 17 men and 22 women hospitalized after becoming infected with the virus, the Times reported. Patients on ventilators were excluded, as were people taking drugs that affect the immune system.

The study supports the idea that a patient's sex should be taken into account when and if a coronavirus vaccine is developed, researchers said.

"You could imagine scenarios where a single shot of a vaccine might be sufficient in young individuals or maybe young women, while older men might need to have three shots of vaccine," Dr. Marcus Altfeld, an immunologist at the Heinrich Pette Institute and at the University Medical Center Hamburg-Eppendorf in Germany, told the Times.

Sources:

Nature. "Sex differences in immune responses that underlie COVID-19 disease outcomes"

New York Times. "Why Does the Coronavirus Hit Men Harder? A New Clue"