Specific types of immune responses fade quickly in older people immunized against Covid-19, Elizabeth Tracey reports


We know that Covid viruses bind to a cell surface protein known as ACE2, and that antibodies can block the virus at this location as well bind directly to the virus, so called neutralizing antibodies. Research by Johns Hopkins geriatrics expert Sean Leng has shown that in older people who are vaccinated against Covid, these responses fade quickly.

Leng: The issue is actually the immunity wanes particularly when you looked at the functional aspect, the ACE2 inhibition as well as the neutralizing antibody titers, it actually went down pretty much immediately at the three months time point, and by the six month time point after the second dose, the initial series of two dose vaccination, particularly the ACE2 inhibition, that went down almost back to the baseline. It looked like those people have never been actually vaccinated.  :29

Leng says this points to the need for well timed boosters especially for those who are older. At Johns Hopkins, I’m Elizabeth Tracey.