Individuals with severely weakened immune systems are to receive a third dose of coronavirus vaccine as standard following new advice from the Joint Committee on Vaccination and Immunisation.

The Government has accepted advice from the JCVI stating that people over 12 who were severely immunosuppressed at the time of their first or second dose should be offered a third jab. This includes those with leukaemia, advanced HIV and recent organ transplant recipients.

This is because data has shown that some people with underlying conditions or who take certain medications “may not mount a full response to Covid-19 vaccination,” although preliminary results from UK studies suggest “only a modest reduction in vaccine effectiveness against symptomatic Covid-19” among immunosuppressed patients, says the Department of Health and Social Care.

This advice is not connected with the widely anticipated Covid-19 booster programme for the general population, which the JCVI’s professor Anthony Harnden has said is “highly likely” and will “be decided over the next few weeks”.

Health secretary Sajid Javid said: “We know people with specific conditions that make them particularly vulnerable to Covid-19 may have received less protection against the virus from two vaccine doses. I am determined to ensure we are doing all we can to protect people in this group and a third dose will help deliver that.

“The NHS will contact people as soon as possible to discuss their needs and arrange an appointment for a third dose where clinically appropriate.

“This is not the start of the booster programme – we are continuing to plan for this to begin in September to ensure the protection people have built from vaccines is maintained over time and ahead of the winter. We will prioritise those most at risk to Covid-19, including those who are eligible for a third primary vaccine, for boosters based on the final advice of the JCVI.

“Covid-19 vaccines have saved more than 105,000 lives and prevented 24 million infections in England alone. They are building a wall of defence and are the best way to protect people from serious illness. I encourage everybody who is eligible to get their jabs as soon as they can.”

Deputy chief medical officer Jonathan Van-Tam said: “We should be doing all we reasonably can to ensure that this group is not disadvantaged and a third primary dose is one step in this direction.

“We are also working hard to ensure there are other medical interventions that can be used in these groups, including specific treatments like antivirals and monoclonal antibodies.”