UK Health Security Agency News and Media

15 Nov 2021

JCVI issues advice on COVID-19 booster vaccines for those aged 40-49 and second doses for 16-17 year olds

  • The JCVI is now advising that those aged 40-49 years will be eligible for a booster vaccine 6 months after their second dose
  • Separately, the JCVI is advising that a second dose of the COVID-19 vaccine should be offered to 16-17 year olds who are not in a COVID-19 at-risk group

Updated advice on COVID-19 boosters

JCVI has advised that, in addition to those aged over 50 years and at higher risk from COVID-19, all adults aged 40 to 49 years should be offered a mRNA booster, six months after their second dose, irrespective of the vaccines given for the first and second doses.

Recent UK and international data have provided early signs of a slight fall in the levels of protection against severe disease from the primary doses, in those who had their initial vaccines a long time ago. Booster vaccines are being offered to eligible groups to help them maintain high levels of protection against hospitalisation, severe illness or dying over the winter.

The vast majority of the UK adult population has received a COVID-19 vaccine since the programme was launched in December 2020 – including 87.9% of the population who have received a first dose and 80% who have received two doses.

JCVI has previously advised booster vaccination for all adults aged 50 years and over, and those in a COVID-19 at-risk group. The offer has now been broadened to include those aged 40-49 years.

Booster vaccination should be with either the Pfizer-BioNTech vaccine, or the Moderna vaccine, as previously advised. Both of these vaccines are expected to give a good level of extra protection.

The advice comes as the UKHSA publishes the first data on booster vaccine effectiveness in the UK. The analysis shows that people who take up the offer of a booster vaccine increase their protection against symptomatic COVID-19 infection to over 90%. Protection against more severe disease is expected to be even higher.

Following two doses of the vaccine, as yet, there is no robust evidence of a decline in protection against severe COVID-19 (hospitalisation and deaths) in those aged under 40 years. JCVI will continue to closely review all available data to develop further advice in due course.

JCVI issues advice on second doses for 16-17 year olds

The JCVI is advising that all 16 – 17-year olds who are not in an at-risk group should be offered a second dose of the Pfizer vaccine. The second vaccine dose should be given 12 weeks or more following the first vaccine dose.

For those in this age group who have had COVID-19 infection, the second vaccine dose should be given 12 weeks or more following the first vaccine dose, or 12 weeks following a positive COVID-19 test result, whichever is later.

This advice is in addition to the existing offer of two doses of vaccine to 16 – 17 year olds who are in ‘at-risk’ groups, as described in the Green Book.

The decision to advise the second dose is based on a review of the latest evidence of the benefits of the vaccine programme, compared to the risks of any side effects. A second vaccine dose increases the level of protection and is important for extending the duration of protection. As protection from the first dose will eventually start to decline, the benefits from the second vaccine dose will become more important over time. A second dose may also offer a reduction in the risk of hospitalisation and onward transmission to vulnerable close contacts.

In reports originating from outside the UK, extremely rare adverse reactions, such as myocarditis (inflammation of the heart) have been reported more frequently after the second vaccine dose compared to the first vaccine dose. However, in countries such as Canada and the UK who have a longer interval between the first and second doses, rates following the second vaccine dose are closer to the reporting rate after the first dose.

The latest available data indicate that myocarditis following vaccination usually resolves within a short time, most cases respond well to treatment and where information is available, no major complications have been identified in the medium term (months).

Taking these factors into consideration, JCVI has concluded that the balance of risks and benefits supports offering a second dose of the Pfizer-BioNTech COVID-19 vaccine in persons aged 16 – 17 years who are not in an at-risk group.

Professor Wei Shen Lim, Chair, COVID-19 immunisation, JCVI said:

“Booster vaccine doses in more vulnerable adults, and second vaccine doses in 16 – 17 year olds are important ways to increase our protection against COVID-19 infection and severe disease. These vaccinations will also help extend our protection into 2022.  

“If you are eligible, please make sure to have these vaccines and keep yourselves protected as we head into winter.”

Contact Information

Sarah Cowen-Rivers

Notes to editors

Those responsible for implementing and the deployment of COVID-19 vaccination for 16-17 year olds should be appropriately trained and confident in providing information to enable young people aged 16-17 to take up their offer of the second dose of the Pfizer vaccine. It is also important that those with parental responsibility provide young people with information regarding the risks and benefits to aid them in making this decision.

If younger people experience any of the following symptoms after receiving their vaccination, they should call 111 or see their GP:

  • pain and/or tightness in the chest which may spread across the body
  • pain in the neck that may spread across the shoulders and/or arms
  • shortness of breath when lightly exercising or walking
  • difficulty breathing when resting or feeling light-headed
  • flu-like symptoms such as a high temperature, tiredness and fatigue
  • palpitationsor an abnormal heart rhythm
  • feeling like you need to be sick

More information on myocarditis and pericarditis is available from the British Heart Foundation.