England is not alone in being particularly hard hit this flu season, with Australia suffering its worst flu season in two decades and the US now grappling with a severe flu outbreak.

However, the situation could have been eased by the use of the quadrivalent vaccine (QIV), however, it was deemed too expensive at £8 and the cheaper trivalent vaccine, at £5, was recommended instead.

Now, NHS England has reacted by offering guidance to make it available to those younger than 65, who are deemed at risk. As suggested by the name, the vaccine is able to protect against four strains of flu – two strains of influenza A and two of influenza B.

Coming under the umbrella of this protection is the so-called “Japanese flu” (B-Yamagata), which has been responsible for many of the admissions to hospitals in the UK during this winter season.

In addition, a new vaccine, known by its brand name of Fluad, is recommended for those over 65 – as it is found to boost the immune system of those receiving the jab. This makes it particularly effective in protecting those aged 65 and over, whose immune system tends to not be as strong as younger members of the population.

The letter, which was sent out to those responsible for ordering in vaccines, read: “GPs and community pharmacy contractors should review all orders (provisional and firm) for the 2018-19 season and ensure these are in line with the evidence-based clinical view i.e. 65 year olds and over to receive aTIV, and under 65s in at risk groups, including pregnant women, to receive QIV for the 2018-19 flu season.

“Suppliers have confirmed that there will be enough adjuvanted trivalent vaccine and quadrivalent influenza vaccine to meet demand. Orders will need to be placed by 29 March 2018. If you encounter any difficulties from a manufacturer placing or amending an order, please advise your local NHS England team.”

Though the letter stressed that suppliers are able to meet demands, already this is being questioned. There is only one supplier of the aTIV and two manufacturers of the QIV – with concerns that the immediate increased demand placed on their production may be too much for the companies to cope with.

There is also concern that the advice may come too late for some, who may have already ordered vaccines based on previous guidance.