连结：https://www.nytimes.com/2021/12/23/health/booster-protection-omicron.html
两针AZ后打BNT或莫德纳
Among people who received two doses of the AstraZeneca vaccine, a booster
with one of the mRNA vaccines, made by Pfizer and Moderna, was 60 percent
effective at preventing symptomatic disease two to four weeks after the shot.
After 10 weeks, however, the Pfizer booster was just 35 percent effective.
The Moderna booster was 45 percent effective at up to nine weeks.
2-4周 有症状保护力60%
10周以上 BNT 35% 莫德纳45%
For people who were given three Pfizer doses, vaccine effectiveness dropped
from 70 percent one week after the booster to 45 percent after 10 weeks.
Pfizer recipients who received a Moderna booster, on the other hand, seemed
to fare better; their vaccine regimen remained up to 75 percent effective at
up to nine weeks.
BNT三针 一周后保护力70% 十周后45%
莫德纳 九周后75%
但英国打BNT应该还是多很多，可能有总数上的差异
简而言之，打第三针还是不能防感染