Friday, March 19, 2010

Immunization Debates Generate More Heat Than Light - We Need Facts on Vaccinations

Unless you have been on mars for most of the last twelve months you would have heard about the H1N1 virus also known as swine flu. In response to the perceived “killer” virus, governments around the world ordered mass dosages of a vaccine against the virus in a bid to save the populace from the terror of flu.

As things turned out there was no threat and many governments in the northern hemisphere have scaled back their orders considerably. In fact latest figures from the USA show that this flu season has been particularly mild with far less cases than usual. The Australian government was not able to cut back its order and hence has a lot of vaccine in storage. It is looking to get rid of this by another scare campaign about second waves (which is tricky when there was no first wave).

Through all this though there has not been any questioning of the basic assumption that giving people a flu vaccine protects them from flu and that in turn they and society benefit. Many countries have annual flu vaccination programs for those over 65. Some of these have been going for many years.

It was with some interest then that it emerged recently that there is not actually any evidence to show that this does any good! The well-respected Cochrane collaboration released a report, which looked at 75 studies over a 40-year period. The conclusion was that “The available evidence is of poor quality and provides no guidance regarding the safety, efficacy or effectiveness of influenza vaccines in people aged 65 years or older”.

In simple terms after 40 years we do not know if giving people over 65 a flu vaccine does any good or any harm. Now to be fair there is nothing at all to suggest that there is any harm done even though the safety of its use has not been proved. Also it could be that nobody was able to find the evidence of benefit even though it may be there.

However after 40 years and 75 studies on a commonplace medical procedure you would expect evidence of benefit to be apparent. The assumption that because it involves vaccination it must be good is not a scientific position but one of faith. Interestingly it is exactly the type of criticism that is leveled at those opposed to vaccines by health authorities and doctors. Unfortunately “debates” over vaccination generate heat and no light as positions are entrenched and facts are of little interest.

Some drugs are more useful than others. Those, which are shown to be not useful, go out of use. Medical procedures too, become superseded. There is no reason the same logic should not apply to vaccination. Those, which are shown to be useful, should be continued. Those where there is not shown to be benefit should not.
Last year serious questions were raised over the papiloma virus vaccine (marketed as the Cervical Cancer vaccine) as how long it lasts in the system is unclear and by giving it to 13 year old it may have worn off by the time they need protection. Also there is the lingering question about whether the body will in most cases clear the virus anyway.

An Australian report showed that after the introduction of the Chicken Pox vaccine there was an increase in the rate of hospitalization of the elderly with Shingles, which is caused by the same virus. This led a call for another vaccine program. Whilst there was a reduction in cases of chicken pox, in children this is hardly a massive achievement as it is essentially a minor childhood illness (yes there can be complications but this is rare).

The bottom line is that this matters. Governments spend large sums of money on vaccine programs. There is in many instances some compulsion about being vaccinated and penalties for not doing so. This does not occur with any other area of medicine. Assessments made on the basis of facts, not pre conceived notions, faith in vaccines, or opposition to vaccines, is what is needed. Those, which are shown to have benefits outweighing risks, are worth doing. Those where this is not the case, are not worth continuing.

Vaccination is a medical and public health issue. It is not a sacred cow. Programs need to be assessed, criticized and changed or stopped if not found to be of benefit. Justification on the basis that vaccination, of itself, is good is no better an argument than vaccination, of itself, is bad.

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