People with extra weight may struggle to mount a robust immune response to the coronavirus — and may respond poorly to a vaccine.
In early April, Edna McCloud woke up to find her hands tied to her hospital bed.
She had spent the past four days on a ventilator in a hospital in St. Louis County, Mo., thrashing and kicking under sedation as she battled a severe case of Covid-19.
“They told me, ‘You were a real fighter down there,’” recalled Ms. McCloud, a 68-year-old African-American retiree with a history of diabetes and heart problems. She weighed close to 300 pounds when she caught the coronavirus, which ravaged her lungs and kidneys. Nearly six months later, she feels proud to have pulled through the worst. “They said people with the conditions I have, normally, this goes the other way,” she said.
As rates of obesity continue to climb in the United States, its role in Covid-19 is a thorny scientific question. A flurry of recent studies has shown that people with extra weight are more susceptible than others to severe bouts of disease. And experiments in animals and human cells have demonstrated how excess fat can disrupt the immune system.
But the relationship between obesity and Covid-19 is complex, and many mysteries remain. Excess weight tends to go hand in hand with other medical conditions, like high blood pressure and diabetes, which may by themselves make it harder to fight Covid-19. Obesity also disproportionately affects people who identify as Black or Latino — groups at much higher risk than others of contracting and dying from Covid-19, in large part because of exposure at their workplaces, limited access to medical care and other inequities tied to systemic racism. And people with extra weight must grapple with persistent stigma about their appearance and health, even from doctors, further imperiling their prognosis.