This site is intended for health professionals only

Show us the evidence for the flu jab

GPs aren't ‘selfish' for refusing flu vaccinations, says Dr Margaret McCartney – they're just not convinced that it's evidence-based.

There's something unsettling about being told that your evidence-based decision making is ‘selfish'.

The chief medical officer, Dame Sally Davies, recently told the press that doctors not rolling up their sleeves for flu vaccination were guilty as charged.

She told the Daily Telegraph: ‘It's selfish [of] healthcare workers, if they don't protect their patients from infecting them, if they don't make sure they are fit to go to work, to look after their families and not take it home too. So we are making a noise and a big effort to try to improve that.'

Noise there is. The Daily Telegraph went on to report that doctors and nurses were ‘putting lives at risk' by refusing to be vaccinated, and said a study had found ‘dozens of patients have either died or become seriously ill' after catching the virus in hospital.

Well, the reason some professionals don't get vaccinated is to do with the evidence – or lack of it.

Do we really know that vaccination of frontline healthcare workers will reduce flu rates among patients?

Many vaccinations are strongly evidence-based – MMR, for example – but the flu vaccination industry seems to have sneaked in under the cloak of respectability and assumed itself a vital role in our winter armoury.

Cochrane reviews

Far from being highly evidence-based for healthcare workers, it is actually an intervention that is largely carried out on the basis of faith. A Cochrane review in 2010 found that ‘there is no evidence that vaccinating healthcare workers prevents influenza in elderly residents in long-term care facilities'.1 

The authors recommended high-quality randomised controlled trials to attempt to answer this question better.

It's worth noting that Cochrane also published a review asking if flu vaccination prevented influenza in healthy adults (whom we could presume would make up the majority of healthcare workers being told they should have the vaccine).2

The researchers concluded: ‘Thirty-three healthy adults need to be vaccinated to avoid one set of influenza symptoms. In average conditions (with a partially matching vaccine) 100 people need to be vaccinated to avoid one set of influenza symptoms. Vaccine use did not affect the number of people hospitalised or working days lost, but caused one case of Guillian-Barré syndrome for every one million vaccinations.' Hardly a ringing endorsement.

The authors also noted that pharma-funded trials tended to be positive, but that publicly funded trials did not. They added: ‘The review showed that reliable evidence on flu vaccines is thin, and that there is evidence of widespread manipulation of conclusions and spurious notoriety of the studies.'

The independent Drugs and Therapeutics Bulletin also reviewed the evidence,3 and it concluded that staff working in long-term care facilities might be able to reduce risk of influenza-like illness in residents through their own vaccination, but ‘outside long-term care settings, there is a lack of evidence to justify such vaccination'.

This didn't, however, stop Professor Peter Openshaw, director of the Centre for Respiratory Infection at the National Heart and Lung Institute, Imperial College London, telling the BMJ that he thinks ‘all healthcare staff should wear badges saying "I've been vaccinated and ask me why."' He added: ‘I can see no ethical or moral reason why we should not all be vaccinated.'

But without evidence, our jolly little badges may as well say we've taken homeopathy. The research led by Professor Openshaw and later cited in the Daily Mail was a descriptive study of patients developing H1N1 flu in hospital,4 and not a trial about staff vaccination.

It's misguided to stick a badge on a problem like this – wasting our time and effort, and spreading fear when the real issue is a lack of evidence.

Rather than scolding us, those doctors working for the Government would do better to address the evidence gap by inviting us to take part in a randomised controlled trial. No such luck.

Have a look on PubMed and you'll see dozens of studies offering potential ways to increase flu vaccination uptake in healthcare staff. Yet where is the evidence that it benefits patients or staff? Medicine is at its worst when it ignores evidence and takes refuge in name-calling.

Dr Margaret McCartney is a GP in Glasgow


1 Thomas RE et al. Influenza vaccination for healthcare workers who work with the elderly. Cochrane Database of Systematic Reviews 2010;2:CD005187

2 Jefferson T et al. Vaccines for preventing influenza in health adults. Cochrane Database of Systematic Reviews 2010;7:CD001269

3 Seasonal flu vaccination for healthcare workers? DTB 2010;48:122-5

4 Enstone JE et al. Nosocomial pandemic (H1N1) 2009, United Kingdom, 2009-2010. Emerg Infect Dis 2011;17:592-8