Should boys and girls be vaccinated against HPV, the virus that causes cervical cancer? The government's proposed introduction of a national vaccine programme demands the scrutiny of us all. Website editor Jim Pollard researched the FAQs.
What is HPV?
Human papilloma virus (HPV) is a sexually-transmitted virus. There are about 100 different strains, of which about 40 can infect the genitals.
The vast majority cause no ill-effects. But strains HPV 16 and 18 cause cervical cancer, a disease which kills over 1,100 women in the UK every year. Other strains such as HPV 6 and 11 can cause genital warts.
There is a 10-20 year gap between HPV infection and the development of cervical cancer.
Can vaccination protect against it?
At the Health Protection Agency's annual conference last month, modelling data was presented which suggested that up to 70% of cases of cervical cancer and 95% of cases of genital warts could be prevented by the introduction of HPV vaccination.
Is the HPA model reliable?
The HPA themselves say: 'there is considerable uncertainty in many key factors used in this modelling work, and the team notes that careful monitoring of the effectiveness of HPV vaccination will need to be in place to assess the true impact of a programme in the UK.'
Who will be vaccinated?
In June, government advisors recommend girls aged between 12 and 13 in the UK should be vaccinated against the HPV .
The Department of Health agreed, in principle, to introduce HPV vaccines routinely for these girls, 'subject to independent peer review of the cost benefit analysis. Funding for this will be considered in the context of the Comprehensive Spending Review'.
Why so young?
To be most effective the vaccine needs to be given before girls contract HPV. Research by the HPA suggests that at least one 16 year-old girl in 10 girls in England already has the virus and that the risk of infection is 'substantial' by the age of just 14.
Why the sudden talk of vaccination?
The vaccine drugs have only very recently been approved for use.
In June 2006, the FDA in the US approved Gardasil made by Merck. The EU followed suit in September 2006.
A rival drug called Cerverix made by GlaxoSmithKline which is already being used in the Phillippines was approved in May this year in Australia and on 24 September in the EU.
If they're new I bet they're expensive.
You're right. Gardasil, which will be given in three doses, costs £250 per girl.
The US state of North Carolina, for instance, which currently spends $11 million annually on seven vaccines for every child reckons Gardasil would probably nearly double its bill to $21 million.
Are it worth it?
The HPA's modelling suggests vaccination will be cost-effective (or, as they put it, an effective use of health care resources), 'if the vaccine protected girls against the virus for at least 20 years'.
And will it?
We don't know. These are new drugs and the long-term effects both good and bad are unknown.
To date, the drugs are not yet widely-used although this is about to change. International not-for-profit organisation Path is pioneering use of the vaccine in developing countries and by the end of 2007, will have pilot programmes in India, Peru, Uganda, and Vietnam.
Of course, the balance of the argument is very different in countries where there no programme of cervical screening and where vaccination is the only way of saving lives.
Are there side-effects?
Again we don't really know.
There have been side-effects from the use of Gardasil, mostly minor, although as of 31 July 2007, there had been seven deaths reportedly related to its use. The vaccine is not recommended for pregnant women.
Does a vaccine mean we'll no longer need cervical screening?
No. The vaccine would be in addition to the NHS Cervical Screening Programme.
Professor Pat Troop , Chief Executive of the HPA says: 'Cervical screening will remain important and the best way for older women (who are unvaccinated) to reduce their risk of cervical cancer. Also, current vaccines do not protect against all HPV types that cause cervical cancer, and screening will remain the best way to protect against disease caused by these other types.'
But if HPV is sexually-transmitted don't we need to vaccinate boys as well as girls?
The vaccine is not yet approved for use in boys but Merck in working on it. The New York Times reported that if the company is successful in this, analysts expect that sales could surpass $4 billion by 2010.
But is it right to vaccinate boys for a disease they'll never get?
That's the question the MHF is currently wrestling with. Of course, boys will benefit to a small extent. They'll be protected against genital warts and anal cancer. But it's true that the main benefit — protection from cervical cancer — will only be for the women with whom they have sex.
MHF policy officer David Wilkins who has been following the debate closely points out that 'although it appears unusual to vaccinate people against a disease they will not get, a similar principle applies with German measles vaccine. The disease is not serious for those of us who are vaccinated but it is dangerous for unborn babies if their mothers get it. In other words, we're primarily vaccinated not for our own benefit but for soemone else's.'
Will boys just be guinea pigs?
No more than the girls. To some extent, the introduction of any vaccination programme involves using the population as guinea-pigs but the usual argument is that the benefit — protection against serious disease for the many — out-weighs the disadvantage — relatively minor side-effects for the few.
Having said that, the debate about the supposed link between MMR and autism really tested the strength of this bargain between state and citizen. No link at all has ever been proved in this case but, because it is impossible to prove a negative, the row has raised questions about our attitudes to vaccination in general.
Certainly whether the state has the right to oblige us to take a vaccine or any other drug is a question all citizens have a right to ask.
So what's best?
Mark Jit, who led the research for the HPA, says: 'our models suggest that vaccination could play a beneficial role in preventing cervical cancer and genital warts in the UK . The benefits to health would be worth the cost of vaccination if our model assumptions are correct. However, there are still uncertainties in the model. If a decision is made to proceed with HPV vaccination, then follow-up of vaccinated women for several decades will be important to verify predictions about the long term impact of vaccination.'
Page created on October 1st, 2007
Page updated on December 18th, 2009