What explains Covid-19’s lethality for the elderly? Scientists look to ‘twilight’ of the immune system
Researchers on Monday announced the most comprehensive estimates to date of elderly people’s elevated risk of serious illness and death from the new coronavirus: Covid-19 kills an estimated 13.4% of patients 80 and older, compared to 1.25% of those in their 50s and 0.3% of those in their 40s.
The sharpest divide came at age 70. Although 4% of patients in their 60s died, more than twice that, or 8.6%, of those in their 70s did, Neil Ferguson of Imperial College London and his colleagues estimated in their paper, published in Lancet Infectious Diseases.
The new estimates come as scientists have been scrambling to figure out the underlying reasons for older people’s greater susceptibility to the virus — and, in particular, why some mount a stronger
