England’s top doctor has appealed for those eligible to get their spring Covid jabs, as he warned “we cannot let the recent sunshine fool us”. Some 7.3 million people are eligible for a booster vaccination in this round. Three million have received jabs since the rollout began last month.

With six weeks to go, the health service is urging those at highest risk of severe illness to come forward. Professor Sir Stephen Powis, NHS England’s national medical director, said: “Covid-19 is not just a winter illness and we cannot let the recent sunshine fool us into thinking it is no longer a threat.

“The virus continues to be dangerous for those most at-risk, particularly older people and those with weakened immune systems

, so we are encouraging all those who are eligible to come forward as soon as possible and join the three million people already vaccinated so far over the last month.

“Previous immunity can wane over time, so it is important to top-up your protection and while we are sending out invites, you do not need to wait for this to book.

“Just visit the NHS website, use the NHS App or call 119 to get an appointment in your diary.”

Those eligible for the jab to top-up protection include all over 75s and people who have weakened immune systems.

More than 9.7 million invitations and reminders have been issued by text, email, letters or through the NHS app.

NHS teams are also visiting care homes to ensure elderly people are protected.

Minister for Public Health and Prevention Ashley Dalton said: “The Covid-19 vaccine is a crucial weapon in the fight to protect those most vulnerable to serious illness.

“That is why it is essential that everyone who is eligible for the spring jab gets it as soon as possible and tops up their protection.

“You can get yours for free at thousands of sites open across the country, including local pharmacies and GP practices.”