The T-cell COVID cavalry

The vaccines generate antibodies against Covid, but those defenses have been found to be less effective over time. T cells, a type of white blood cell, are a second line of defense that have held up better. The Dutch study found that while antibody responses fade against Omicron, the T cell response remains robust.

This may explain why Omicron infections so far appear to have resulted in relatively fewer hospitalizations and deaths. While antibodies block infection, T cells attack and kill cells that are infected. This helps reduce the spread of the disease. So far at least, Omicron infections among the vaccinated don’t seem to attack the lungs the way other variants have.