The jab is typically formulated to protect against several strains of the virus. In February, the World Health Organisation (WHO) advised on what to include in flu vaccines for countries in the northern hemisphere.
But a pharmaceutical company that develops vaccines is concerned that the lack of influenza data collected during the Covid pandemic could result in the jab being ineffective against some flu variants.
There has been a 62 per cent drop in shipments of influenza surveillance samples due to countries having closed their borders and restricted travel during the coronavirus pandemic.
It is feared that all these aggravating factors as well as lower natural immunity to the flu among the general population, and high levels of Covid infection, could lead to pressures on the NHS.
Dr Beverly Taylor, of pharmaceutical company Seqirus – which provides the UK with flu jabs, told the Daily Telegraph: “We saw quite a big reduction in the labs supplying the genetic sequence data to WHO, and around September last year we saw a 94 per cent drop in the genetic sequence data that was reported into the database.
“So this has had a massive impact in the reporting. We could have reduced the opportunity to identify viruses as they emerge. We certainly have reduced the opportunity to look at which vaccines would give the best overall protection and the best coverage of all the circulating viruses.
“What we’re actually seeing is influenza in geographical pockets, so it’s very difficult to tell which one is going to be the winner. We could see a mismatch for at least one of the subtypes.”
The warning comes after the Department of Health and Social Care announced in July that it would be rolling out this winter its biggest flu jab scheme “in history”.
It said that 35 million people would be offered the jab, more than half of the population of the UK, following the success of the Covid-19 vaccination roll-out.
From September, the jab will be offered to all children aged 2 and 3, and all children in primary school and in secondary school up to year 11.
Those aged six months to under 50 years old in “clinical risk groups”, pregnant women, those aged 50 and over, unpaid carers, close contacts of immunocompromised individuals, and frontline health and adult social care staff, will also be offered a vaccination.
Health and social care secretary Sajid Javid said: “Flu can be a serious illness and we want to build a wall of protection by immunising a record number of people.
“With the nation getting closer to normal life, we must learn to live with Covid-19 alongside other viruses and we’re offering the free flu jab to millions more people to help keep them safe this winter.
“The phenomenal scale of the Covid-19 vaccination programme is a clear demonstration of the positive impact vaccination can make and I encourage all those eligible to get their flu jab when called forward.”
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