a The booster vaccination plan is “urgent” because the protection offered by two doses of Pfizer and AstraZeneca could drop as low as 50 percent for older adults by winter, a senior scientist warned.
Professor Tim Spector, chief scientist at the Zoe Covid study app, said the results showed that protection from two vaccines begins to wane “even within six months”.
“In my opinion, a plausible worst-case scenario could see less than 50 per cent protection for seniors and health care workers by winter,” he said.
“If there are high levels of infection in the UK, driven by relaxed social restrictions and a highly transmissible variant, this scenario could mean increased hospital admissions and deaths.
“We urgently need to make plans to boost vaccines, and determine if a strategy to vaccinate children is reasonable.”
Zoe’s latest analysis, based on test results from 1.2 million users of the app, suggested that Pfizer jab was 88 percent effective in preventing Covid-19 infection a month after the second dose, but this fell to 74 percent after five to six months. .
For the AstraZeneca vaccine, protection decreased from 77 percent per month after the second dose to 67 percent after four to five months.