Virologist says why it's hard for elderly to develop immunity to COVID

Re-infections with coronavirus are most common among older adults, Report informs, citing the virologist, head of the Genome Engineering Lab at Moscow Institute of Physics and Technology Pavel Volchkov’s interview with Izvestia.

“It happens for the same reason that affects the high mortality rate in age groups - due to the aging of the immune system along with the entire body. Our adaptive immunity (B-cell and T-cell) has its own age stages: many T cells and B cells are produced in childhood, in adolescence, and less as we grow up. And in old age, new B and T cells are practically not formed,” the specialist explained.

“A specialized primary lymphoid organ, the thymus, is responsible for the production of T cells. By the age of 40–50, the thymus dissolves and practically disappears. In older people, it is almost nonexistent, so new T cells are not produced. Adults, and especially the elderly, live with the set of T cells that they have managed to form earlier,” Pavel Volchkov noted.

Nevertheless, according to the virologist, older adults still develop immunity to something new, it is simply not as effective as in children, young adults, and middle-aged people. It is important to carry out mass vaccination to protect elderly citizens. This is the only way to cope with the COVID-19 pandemic.