Flu vaccination: worthwhile for most?

Flu vaccination season rolls around again, but what is the evidence for the benefit of mass flu vaccination of the general population? A review published recently in BMJ (British Medical Journal) cuts through the fog of assumptions:

"For each healthy adult, a Cochrane review found that vaccination saved an average of just 0.04 days off work and concluded that no evidence supported it as a routine public health measure."

No real evidence for seniors either

"And among over 65s, Cochrane reviews found only poor quality data and were unable to draw conclusions of any benefit, thus recommending more trials."

Similar paucity of evidence for children

"As for children, Cochrane again found the available studies to be of poor quality: the number needed to vaccinate to prevent one case ranged from seven (live vaccine) to 28 (inactivated vaccine), and effectiveness varied greatly depending on the season."

Interestingly, the authors of the Cochrane review of studies on flu vaccination for children state:

"This review includes trials funded by industry. An earlier systematic review of 274 influenza vaccine studies published up to 2007 found industry-funded studies were published in more prestigious journals and cited more than other studies independently from methodological quality and size. Studies funded from public sources were significantly less likely to report conclusions favourable to the vaccines. The review showed that reliable evidence on influenza vaccines is thin but there is evidence of widespread manipulation of conclusions and spurious notoriety of the studies."

Flu vaccination for healthcare workers?

While there is evidence to support flu vaccination in select categories such as pregnant women and patients with COPD, it appears not to yield any significant benefit when applied to healthcare workers attending the elderly:

"The evidence is uncertain among people with asthma; however, flu vaccination does seem to usefully reduce exacerbations in people who have chronic obstructive pulmonary disease. And a review of flu vaccination trials for healthcare workers who looked after older people in long term residential care found no meaningful difference in the number of cases of laboratory confirmed flu, admissions to hospital, or deaths from respiratory infections in residents."

Four 100ths of a day saved

Dogma in the UK is pretty much the same as here according to policies advanced by the NHS (National Health Service) and hardly justified by the result:

"The NHS has a “Flu Fighter” campaign to encourage uptake and offer incentives for staff to bare their biceps. In return for vaccination, hospitals have offered their staff entry into cash prize draws, as well as chocolates, lollipops, cakes, biscuits, stickers that read “I’m a Flu Fighter,” and even an extra day’s annual leave, some freedom of information requests have shown. But will those days off work be offset by the average 0.04 days saved through vaccination?"

The author concludes were her personal view as a practicing physician:

"Treating children is one thing; treating adults like children is quite another. The Department of Health wants trusts to achieve a 75% uptake in flu vaccination for staff, when it would be better off ensuring that resources are used where they can do some good. I would have the vaccination if a high quality trial showed that it was worth it for me or my patients. But flu vaccination is offered millions of times every year at huge opportunity cost; given so much uncertainty, this policy is impossible to justify."

For the record: I am assuredly not 'anti-vaccine', one of the greatest boons of medicine for the world. But both vaccines and patients differ. They should be used when supported by the evidence, with an assessment of each patient's immune status and capacity to respond to the vaccine. Of course it should not be necessary to mention that there are additional supports for resistance to opportunistic infections.