badscienceblogs

Martin 29 September 2009 syndicated No Comment

Statistically speaking, the story that broke last night was tediously inevitable. 1.4 million doses of the Cervarix vaccine have been administered to teenage girls since the program began, and eventually - whether by chance or adverse reaction - one person was bound to die. Yesterday, for whatever reason, that teenage girl was Natalie Morton, and my sympathies go out to her kith and kin. Her death, and the manner of its reporting, will affect public health in ways she'll never know.

There are two possibilities here, reaction or coincidence. As a species we're fairly poor at dealing with probability, and events like this seems far less likely to us than they actually are. The raw facts of the matter are that: a) most teenage girls around Natalie's age will be vaccinated in 2009, and b) a number of teenage girls die every year of initially unexplained causes. The chances of a one of those girls dying on the same day she got her vaccine could be as high as one in a few dozen.

On the other hand it could be an a adverse reaction to the vaccine. The chances of this are also fairly small, but there seems to be a lot of misunderstanding about these risks, largely coming from a misunderstanding of vaccine reaction incidence reports. For example, The Daily Mail make the mistake of suggesting that the Cervarix vaccine has been linked to thirty deaths. Of course it hasn't; the mistake they've made is to use the database of Vaccine Adverse Event Reporting System with the mistaken belief that the data shows confirmed vaccine reactions.

In fact the VAERS simply records people's self-reported ill health occuring around the time of vaccination on the off-chance it might be related. More accurate estimates of risk by the MRHA estimate the risk of severe reactions at around one in a million. To put that into context, about 2% of the population have reactions to penicillin.

The Mail also report that:

Critics say the tragedy highlights the risks of mass vaccination because no testing regime can detect the rarest and potentially most lethal side effects.

These critics appear to be JABS, who were quoted prominently in earlier editions of the Mail's online article, and in their print edition today. I'll move on to that coverage in a moment, but first it's worth pointing out that since he vaccine is likely to save around 700 lives a year, any theoretical, extremely rare side-effects would be comprehensively outweighed by the benefits. It's a self-defeating argument to make.

The response of mainstream media organs has ranged from reasonable (the BBC) to dire (the Daily Mail print edfition); and Malcolm Cole has done an excellent review of the coverage on his own blog, with scores for the various papers.

The Guardian have done an excellent job allaying fears, bringing in a doctor to <a href="
http://www.guardian.co.uk/society/2009/sep/29/cervarix-hpv-vaccine-facts">explain a number of facts about the vaccine and the risks involved. But as usual the Mail and Express lead the way in irresponsible scare-mongering. Take for example the following headline, kindly sent to me by the Daily Quail (click to enlarge to read the whole article). Some journalists consult doctors, the Mail speak to JABS:

It'll be interesting to see if they dare print anything similar in their Irish Edition.

The Mail article is horrendously biased towards sensationalism, and the The Daily Quail have covered it well:

"A statement from the Director of public health for NHS Coventry, saying 'No link can be made between the death and the vaccine until all the facts are known' was relegated to the last line of the report, while no mention was made of how many cases of cervical cancer might be prevented by the vaccination or how many womens' lives saved each year, or any research indicating that the vaccination is in fact safe."

"However, it was noted that 'more than 2,000 have suffered side-effects ranging from rashes to paralysis', and that 'some critics argue [the vaccine] will encourage promiscuity'."

The side effects are of course triflingly minor; while the suggestion that the vaccine promotes promiscuity is completely baseless in fact, a moral authoritarian fantasy idea for which no supporting evidence has been advanced. Taken together with the shocking exclusions of any sort of balancing information about the benefits of the vaccine, and the way in which the article leads the reader towards conclusions about tainted vaccines, and what we have is an incredibly irresponsible and potentially dangerous piece of reporting that will affect uptake of all vacccines.

Science Minister Lord Drayson recently took on Ben Goldacre in a debate at the Royal Institute. I was there, and he claimed repeatedly that newspapers and media outlets had learned the lessons of MMR; that in 2009 similar failures in science reporting wouldn't happen.

The fact is, they haven't. And if this sort of sensationalist, unbalanced and misguided reporting of distorted facts and cherry-picked evidence continues, vaccination rates will fall again, and diseases which have no business still existing in the 21st century will continue to plague us.