Protection linked to obesity
Another finding that ran against the scientific grain was the data about obesity.
There was a higher and more persistent antibody performance among people with a BMI of 30 kg/m2.
This could relate to greater disease severity and/or a more pronounced initial response to infection among the obese group.
“Our hypothesis is that patients with obesity begin with a more pronounced response – reflected also by the disease manifestation – and the trend of decline is similar, therefore the kinetics of immune response remain higher throughout the study,” Dr. Cohen said.
“The results in the obese group were indeed unexpected and need further research to confirm or dispute,” said Dr. Schaffner, who is also the current medical director of the National Foundation for Infectious Diseases. “Obesity does predispose to more severe disease.”
Before the boosters
Along with using participants from only the earlier part of the pandemic, another limitation of the study was that the vaccinated group had only two doses of vaccine; boosters were not given during the time of the study, Dr. Schaffner said.
“Again, not the current situation.”
“That said, the strength and duration of natural immunity provided by the early variants was solid for up to a year, confirming previous reports,” he said.
A version of this article first appeared on Medscape.com.