Vaccination of all healthcare workers is widely recommended by health authorities and medical institutions and support for mandatory vaccination is increasing. This paper presents the relevant literature and examines the evidence for patient benefit from healthcare worker vaccination.
Published research shows that personal benefit from vaccinating healthy nonelderly adults is small and there is no evidence that it is any different for HCWs [health care workers].
The studies aiming to prove the widespread belief that healthcare worker vaccination decreases patient morbidity and mortality are heavily flawed and the recommendations for vaccination biased.
No reliable published evidence shows that healthcare workers’ vaccination has substantial benefit for their patients—not in reducing patient morbidity or mortality and not even in increasing patient vaccination rates.
The arguments for uniform healthcare worker influenza vaccination are not supported by existing literature. The decision whether to get vaccinated should… be that of the individual healthcare worker, without legal, institutional, or peer coercion.
The growing pressure on HCWs to vaccinate as part of their ethical professional responsibility… is being taken even a step further with recommendations and pressure on institutions to mandate such vaccination at the expense of individual freedom and as a condition for continued employment increases the urgency of examining the evidence. Is it sufficient for such draconian measures?
The discussion of these arguments is based on critical appraisal of the few published studies, mainly randomly controlled trials, examining the effect of vaccination and on relevant systematic reviews
The central effort was directed at taking a fresh critical look at the trials examining patient benefit. The studies’ internal validity (bias, confounding, chance effects), the correlation between their content and conclusions, and their applicability were examined.
The 2010 Cochrane review on vaccines for preventing influenza in healthy adults detected a statistically significant reduction in confirmed influenza cases, the size of which depended on the degree of vaccine matching to the circulating virus.
However, the reviewers point out that the small overall average absolute difference of about 1% suggests that 100 adults would need to be vaccinated to prevent one case of influenza. The review showed that vaccine reduced time off work by an average of 0.13 days. This small effect was of borderline statistical significance.
Vaccination did not have a statistically significant effect on hospitalization or complications, and no evidence was found that vaccines prevent viral transmission.
As the review included industry funded trials, the authors found it necessary to include a warning as to the interpretation of it’s content…
The reviewers suggest that although serious harm from vaccination may be rare it cannot be ignored and conclude that the results of their literature review discourage the utilization of vaccination against influenza in healthy adults as a routine measure.
[T]he repeated conclusion that staff vaccination has preventive value for elderly patients in nursing homes appears to be the result of major methodological errors and wishful thinking. Even when there appears to be less morbidity and mortality in the intervention hospitals this probably resulted from other factors.
The severely biased conclusions of these articles are the crux of the “proof” presented by authorities supporting HCW vaccination.
It is somewhat depressing to see the prejudiced manner in which the literature can be presented, as illustrated by the 2010 CDC advisory committee on immunization practices recommendations on HCW vaccination.
The above reviewed flawed studies are presented by this [CDC] committee as evidence and further support is added by stating: “a review concluded that vaccination of HCP in settings in which patients also were vaccinated provided significant reductions in deaths among elderly patients from all causes and deaths from pneumonia.”
This statement does not correctly represent the referenced 2006 review which presented the flawed data from the two studies published at that time but actually concluded, very differently, that “. . .an incremental benefit of vaccinating health-care workers for elderly people has yet to be proven in well-controlled clinical trials”.
This review was updated in a 2010 Cochrane systematic review… which concluded that “no effect was shown for specific outcomes: laboratory proven influenza, pneumonia, and death from pneumonia…”
“…We conclude there is no evidence that vaccinating HCWs prevents influenza in elderly patients in long term care facilities.” This important and unambiguous conclusion was disregarded by the CDC committee in their recommendations, published six months later, favoring HCW vaccination.
This paper is of special importance due to the increasing pressure to mandate HCW vaccination.
Such drastic action, at the expense of personal freedom, should not be accepted in the absence of very strong evidence for a very strong population benefit. The decision whether to vaccinate is, at present and in most situations, not a moral issue and should remain that of the individual HCW, preferably based on real information.