Two in five over-80s have broken lockdown rules within three weeks of their first Covid vaccine dose, research has shown.
Some 41% of people in the priority group reported they had met with someone other than a household member, care worker or member of their support bubble, indoors, since vaccination.
In contrast, one in five over 80s who have received at least one dose of a vaccine reported they had not left home for any reason since receiving their jab.
The Office for National Statistics (ONS) survey was carried out between February 15 and February 20.
A quarter of over 80s who had only received one vaccine dose reported they would be much or somewhat more likely to attend a hospital for medical reasons since being vaccinated; this increased to one-third for those who had received both doses.
Research by Kings College London suggests that individuals who had received the dose three weeks ago would be 67% protected against the virus.
Official NHS England estimates show that by 21 February 2021, some 2,675,253 over 80s had received their first dose of the vaccine and 342,716 had received their second dose.
While studies have shown that a single dose of the Oxford University and AstraZeneca vaccine can offer 76% of protection from day 22 to day 90 post vaccination, experts have warned the public they must continue to follow social distancing rules.
An official spokesperson for the prime minister said: “It’s important that people continue to follow the guidelines that are in place.”
Asked if the elderly were behaving irresponsibly, the spokesperson replied: “We are asking everybody to continue to follow the rules and guidelines.”
This week health secretary Matt Hancock urged Britons not to “blow” progress. He told a Downing Street press conference that people must “keep sticking to the rules, let’s not blow it now” – but said the new data shows “in the real world, across the UK right now that the vaccine is helping both to protect the NHS and to save lives”.
Deputy chief medical officer Jonathan Van-Tam has said those who don’t, risk prolonging lockdown restrictions.
Professor Van-Tam said that if those who have been vaccinated begin easing off because they are protected, they are potentially putting at risk those further down the priority list who still need inoculation.
Writing in The Sunday Telegraph last month, he said it was still not known if people who had been vaccinated could still pass on the virus to others, even though they were protected from falling ill themselves.
“So even after you have had both doses of the vaccine you may still give Covid to someone else and the chains of transmission will then continue,” he wrote.
“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.
“Regardless of whether someone has had their vaccination or not, it is vital that everyone follows the national restrictions and public health advice, as protection takes up to three weeks to kick in and we don’t yet know the impact of vaccines on transmission.
“The vaccine has brought considerable hope and we are in the final furlong of the pandemic but for now, vaccinated or not, we still have to follow the guidance for a bit longer.”