Prof Van-Tam said “no vaccine has ever been” 100% effective, so there is no guaranteed protection.
It is possible to contract the virus in the two- to three-week period after receiving a jab, he said – and it is “better” to allow “at least three weeks” for an immune response to fully develop in older people.
“Even after you have had both doses of the vaccine you may still give Covid-19 to someone else and the chains of transmission will then continue,” Prof Van-Tam said.
“If you change your behaviour you could still be spreading the virus, keeping the number of cases high and putting others at risk who also need their vaccine but are further down the queue.”
Source: BBC News