Covid protection from two doses of the Pfizer or AstraZeneca vaccines begins to wane within six months, a new study has found.
Analysis from the Zoe Covid study found that in a reasonable “worst-case scenario”, protection could fall to below 50% for the elderly and healthcare workers by winter unless they receive booster shots. The study involved more than 1.2m test results and participants.
After five to six months, the effectiveness of the Pfizer jab at preventing COVID-19 infection in the month after the second dose fell from 88% to 74%,while for the AstraZeneca vaccine, effectiveness fell from 77% to 67% after four to five months.
Under a worst-case scenario, protection could fall below 50% for older people and healthcare workers by the winter, Tim Spector, principal investigator for the ZOE COVID study, said.
“It’s bringing into focus this need for some action. We can’t just sit by and see the protectiveness slowly waning whilst cases are still high and the chance of infection still high as well,” Spector told BBC television.
