Researchers compared people who had received two doses of the Pfizer-BioNTech COVID-19 vaccine to unvaccinated individuals who had recovered from the virus. They found that participants with natural immunity were up to 13 times less likely to contract Covid than those who were given two jabs. The team, from Maccabi Healthcare and Tel Aviv University note that their study - which has not yet been peer-reviewed - has many limitations including the more highly transmissible Delta variant being dominant at the time and participants not being required to be tested. The study looks at breakthrough infections and does not discourage...