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JCVI considering shortening vaccine dose interval to eight weeks


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The Joint Committee on Vaccination and Immunisation (JCVI) is considering shortening the vaccine dose interval to eight weeks for the under-50s, its deputy chair has said.

It comes as the Scottish Government yesterday announced that all second doses should be brought forward for the over-40s if scheduled more than eight weeks after their first dose, in order to combat the ‘Delta’ variant first recorded in India.

It said that the eight-week gap will also apply to the under-40s ‘supplies permitting’.

Northern Ireland last week cut the AstraZeneca and Pfizer vaccine gap to a maximum of eight weeks for all over 18s who haven’t had their first jab, while in Wales it is at the discretion of individual health boards.

Last month, an extra payment of £1,000 was announced for GP-led Covid vaccination sites in England to enable the rebooking of second jabs following the announcement that all risk group patients – including all the over-50s – should now have them sooner.

Speaking on the BBC’s Radio 4 Today programme this morning, deputy JCVI chair Professor Anthony Harnden said bringing forward second doses for the over-40s ‘makes sense’ amid ‘plentiful supply’ of the AstraZeneca vaccine and growing concern around the Delta variant.

He said: ‘We are still vaccinating over 50-year-olds with their second dose in the UK at the moment so we want to complete that and we want to carry on reaching out to those unvaccinated individuals above 50 who are at risk, but as we move down the age groups, particularly with plentiful supply of AstraZeneca vaccine, it would make sense to shorten that dose interval from 12 to eight weeks.’

However, he warned of a ‘short-term trade-off’ as a shorter dosage interval with the AstraZeneca vaccine ‘probably offers less good protection longer term’.

Professor Harnden added that JCVI advice is ‘permissive’ regarding the Pfizer vaccine, saying that second doses ‘can be given between three and 12 weeks’.

Asked about shortening the dosage gap for all adults like in Northern Ireland, he said the JCVI will ‘keep a very close eye on the data as it emerges’ and ‘create policy accordingly’.

He told the programme: ‘Clearly, we want every adult to be offered a vaccination in the country as quickly as possible and we want every adult to have a second dose as quickly as possible. But we want to absolutely make sure that they have reasonably good longer term protection as well, so we’ll keep a very close eye on the data as it emerges.

‘We will discuss this, we’re looking carefully at what the Scottish Government has done – it seems to be a sensible strategy – and we’ll advise the Government accordingly.’

It comes as the Delta variant is posing an ‘emerging problem’ in the UK, Professor Harnden added.

He said: ‘Earlier on in the second wave when we had the Alpha variant [first identified in Kent], we knew that one dose of the vaccine was highly effective against the variant and actually getting many more doses into many more people was the right strategy.

‘But now we know that with this Delta variant the first dose only offers about 33% protection against infection – of course that’s not against serious illness, it will offer more against that – but still it is less than against the Alpha variant and hence the drive to get as many second doses done as quickly as possible.’

The AstraZeneca vaccine is mainly being used to vaccinate the over-40s after it was announced last month that practices should offer patients under 40 an alternative to the AstraZeneca vaccine amid blood clot fears

Meanwhile, the vaccines minister has today urged GPs to ‘maintain momentum’ on the Covid vaccination campaign despite the ‘enormous pressures’ practices are facing in an exclusive blog for Pulse.