“My view is that the focus on increasing staff vaccination rates should be on ensuring that organisations can demonstrate they have offered every single member of staff the chance to have a vaccine and made it easy for them to do so. This is what organisations with high vaccination rates do.”

On the specific issues around Pandemrix and the lack of support for the staff affected by the vaccine, Keogh said: “It would seem both fair and reasonable and in keeping with the values of the NHS that if somebody suffers as a result of trying to do the right thing for others that they would be looked after appropriately.”

Matt O’Neill, chair of Narcolepsy UK, a charity supporting some of the families affected, believes there should be a public inquiry into the use of the vaccines, what was known at the time, and how staff have been treated since.

He said: “NHS staff vaccinated with Pandemrix have been treated pretty disgustingly. Having a vaccination is an act you take on behalf of the community, for the benefit of the herd. When it goes wrong it makes sense that the herd should look after you.”

“More staff would sign up for vaccines if they saw the NHS admit when it went wrong and that it supported staff. At some point, there will be another pandemic and we will need staff to have confidence they will be looked after if something goes wrong.”

In 2010, Andy Burnham, the Labour health secretary at the time, and other ministers contributed to a review of the handling of the pandemic. It said: “[Management] personally would prefer to be criticised for doing too much rather than the alternative, where there could have been unnecessary deaths from doing too little.”

Guy Leschziner, a consultant neurologist at Guy’s and St Thomas’ Foundation Trust, has treated a number of people who developed narcolepsy after having the swine flu vaccine.

On the use of Pandemrix, he told BuzzFeed News: “It’s always easy with the benefit of hindsight. What we have to remember was what was going on at the time, which was that we thought we were going to have an epidemic of a very severe flu. Now today, knowing we didn’t have quite the epidemic we thought we were going to have, you might come to a different conclusion, but at the time we didn’t know that Pandemrix was associated with narcolepsy in comparison to the other vaccine.”

GSK refused to answer questions from BuzzFeed News but issued a statement saying further research was needed to understand what role Pandemrix played in the development of narcolepsy. The company did not renew its licence and the vaccine is no longer authorised by the EMA.

On its website, the EMA said: “Understanding the link between narcolepsy and Pandemrix remains the subject of investigations and may have implications for the future use of similar vaccines.” It said GSK had agreed to continue investigating the vaccine.

Guido Rasi, the executive director of the European Medicines Agency, said: “Immunisation has helped us to bring some major human diseases under control. Worldwide, vaccines are saving the lives of approximately 9 million people every year, more than the whole population of Austria. Today, no child in Europe has to die from formerly common childhood diseases.”

He accepted vaccines were not 100% risk-free but added: “No medicine is. There is a one in a million chance that an adverse event happens. In Europe, we are actively monitoring the safety of medicines, including vaccines, and also looking at all reported side effects. These are recorded in a database and reviewed regularly to identify any potential problem at an early stage.” Around a million reports are made every year.

The Department of Health said its decision to use the vaccine was based on evidence and advice from experts but declined to comment due to the ongoing legal action. Although the DWP has previously admitted causation in the case of Josh Hadfield, it refused to answer questions, saying it would not detail its policy on Pandemrix unless a Freedom of Information Act request was submitted.