What’s the UK’s booster policy ahead of a feared autumn Covid wave?

Covid infections are rising once again in the UK prompting calls for over-75s who have not had their spring boosters to come forward for the shots. But another Covid wave is expected in the autumn. What will happen with boosters then?

What boosters are available now?

The NHS launched the spring booster campaign in March to combat a resurgence of infections caused by the Omicron variant. The first wave in January was mainly due to the BA.1 variant with a subsequent wave in March due to the BA.2 variant.

With over-16s already eligible for two jabs and a booster, the spring shots amount to fourth shots for many people. The spring boosters are still available for the over-75s, care home residents, and those aged 12 and over who have weakened immune systems.

With faster spreading BA.4 and BA.5 variants now pushing up infections and hospitalisations again, Dr Jenny Harries, the chief executive of the UK Health Security Agency, has called on the nearly 20% of the 75-plus group who have not had their spring boosters to come forward for the jabs. The vaccines are not very effective at preventing Omicron infections, but they still reduce the risk of severe disease.

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Will there be another round of boosters?

The current UK wave of Covid is expected to peak in the coming weeks, but another wave is anticipated in the autumn as people move inside with the colder weather.

The government’s independent vaccine advisory group, the Joint Committee on Vaccination and Immunisation (JCVI), has recommended that the NHS and care homes prepare for an autumn booster campaign, which is likely to start in September.

On top of Covid, public health officials fear flu may bounce back hard and early this year, given the experience in Australia, making vaccinations for both flu and Covid a high priority in the autumn.

Who will get an autumn booster?

In May, the JCVI said another round of boosters should be offered to those most vulnerable to Covid before the winter. Under the interim advice, further boosters would be provided to residents and staff at care homes, frontline health and social care workers, all those aged 65 and over, and at-risk adults aged 16 to 64. That amounts to more than 25 million people in the UK.

But the advice is provisional. With Covid still rampant, and the possibility of another troublesome variant cropping up before winter, the plans are not finalised. The JCVI will publish updated advice soon.

Which vaccines will be in the booster programme?

Most people in the UK are offered the so-called mRNA Covid vaccines made by Pfizer and Moderna. Those vaccines, which prime the immune system to defend against the original coronavirus that emerged in Wuhan, are still in stock. But Pfizer and Moderna have tweaked their vaccines for the Omicron era.

Trial data on the updated jabs is still coming through and the vaccines will need to be approved by the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) and recommended by the JCVI before they are offered in the autumn booster programme.

What are the new vaccines?

Moderna’s updated Covid vaccine is a combination or “bivalent” shot that produces spike proteins from both the original Wuhan strain of coronavirus and the first Omicron variant, BA.1. According to the company, the vaccine elicits a “potent” antibody response to the BA.4 and BA.5 Omicron subvariants, which are now dominant in the UK.

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Pfizer has developed a similar bivalent vaccine and an Omicron-specific shot, the latter of which produces spike proteins only for the BA.1 Omicron variant. Last week, the company said the Omicron-specific shot was better than its bivalent vaccine at boosting antibodies against BA.1. More data are being collected on how well the shots work against BA.4 and BA.5.

It is unclear how long the boost from Moderna and Pfizer’s updated vaccines lasts and what impact the shots might have on protecting people from infection and severe disease in the autumn and winter, compared with a booster of the original vaccine formulations.

The MHRA will assess the safety, quality and effectiveness of the tweaked shots once the companies submit the relevant data. If approved, the government will ask the JCVI to advise on which should be used in the autumn booster programme.

In some sense, the decision is a gamble, as no one knows what troubling new variant may emerge later in the year and whether it will be another descendant of Omicron, or a relative of an older variant. The UK’s contracts with Moderna and Pfizer ensure that the country can obtain updated vaccines as the pandemic rolls on.