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HPV not studied enough? You judge

A girlfriend sent me a note today, after my previous blog, saying her GP told her the HPV vaccine has "not been studied enough" and advised her against having her daugther get  it.

I will present a summary of some of the research facts and you can judge.

But first, if you don't trust my interpretation, you can go yourself to read abstracts from all the medical literature at the US National Library of Medicine. The US National Institutes of Health provides an incredible free research tool which is a searchable database of every medical journal in the world. Just put "Pub Med" into google and it will come up. Then in its search bar put "HPV vaccine" ( for everything about it) or "HPV" adverse events" if you are particularly interested in the risks.

The medical language can be hard for neophytes, but I go to Pub Med almost everyday to look up something in my job as a medical writer and summarzing medical literature is a big part of what I do.

Since 2000, there are more than 3100 research studies, commentaries and reviews about the HPV vaccine in the world's medical journals. One or both of the two available vaccines are now licensed in 98  countries and being used in high school innoculation campaigns in hundreds of jurisdictions, including all of the provinces of Canada. Australia has been doing school innoculations since 2006, UK since 2007, so Canada is slow to adopt it as this is the first year it is being offered to highschool girls in mass immunizations. Millions of girls and women have now been vaccinated

  • Prior to licensure in 2006, more than 60,000 young women had been given the vaccine in trials. In that number, the incidence of adverse events following immunization (AEFI) was very low but 60,000 was too small to find the true incidence of serious rare events.
  • In August of this year, the US Centre for Disease Control published in the Journal of the American Medical Association the "Postlicensure Safety Survelliance" of the vaccine now that millions of women and girls have received it. All jurisdicitons report AEFI rate. ( It is a passive system, in that the people doing the shot must report. So some events may go unreported, but not likely the serious ones.)  Here is the most recent AEFI per 100,000 innoculated :
    • 8.2 girls per 100,000 fainted ( syncope)
    • 7.5 had local site reactions
    • 6.8 got dizzy
    • 5.0 were nauseated
    • 4.1 got headaches
    • 2.6 got hives (uticaria)
    • 0.02  ( 2 in a million) got a venous-thromboembolic event (a blood clot) or developed Guillan-Barre syndrome ( they are not clear these events were vaccine related)
    • 0.01 had anaphylaxis and/or died  ( 1 in a million )
    • There have been 32 deaths reported world wide now that upwards of 32 million women have been innoculated. Some of the deaths such as a 14 year old girl in Coventry England two hours after the shot is now being ruled not related.
  • The first women innoculated were back in 1998-1999 in Seattle. IN that research study 100 % of the women with the vaccine were negative for HPV and there were no AEFI except site soreness, dizziness and headache. Koutsky has followed up with 200 of these women and found, 9 years later, more than 90 per cent were still negative.
  • Australia also now has data on about 8 years post vaccine followup. They report an 87 per cent still negative rate  8 years later.
  • There is a lot of debate in the medical literature about the psychological impacts and a number of studies have done surveys of parents and young girls for attitudes. Here are some of the findings
    •   Parents not signing the form, more than 50 percent feel it encourages sex without risk and condones premarital sexual activity. (Hmm, "I would rather have my daughter at risk of cancer, genital warts than have her think sex is normal and healthy.")
    •   Most 11-12 year old girls, when surveyed, say they want the vaccine when told about the pros and cons. Among girls whose parents did not sign the form, 50 per cent said they wanted it but their parents wouldn't allow it.

A lot of debate exists about HPV's impact on the PAP screen and fear that it will undermine the Pap Screen process and the 40 years of its success.  Here is some of that debate:

  • All agree, women must still have regular paps
  • With much fewer cases, will the PAP screen have a higher false negative rate? ( Screeners seeing less cancer, and therefore becoming less good at catching it?)  - This to me is a quality control issue and saying we need more women getting cancer so that our screeners can properly read the slides is a ridiculous argument. We already know in some jurisdicitons, quality control is poor. I say put the resources in primary protection ( stopping it in the first place) and not secondary ( catchng after it has occured and women need invasive treatment to cure it.)
  • 50 per cent of women who get cervical cancer haven't had a PAP in 7 years. Many of these are aboriginal, immigrant or poor women.  Pro side says mass innoculation of young girls removes this socio-economic determinant and levels the playing field. Cons say " we have to reach out to them more and get them regular medical care and not accept the status quo." I say do both -protect all the girls equally now, and work upstream to ensure disadvantaged women are not lost to medical care through life circumstances. Where's the conflict?
  • Cons say only 1,700 women in Canada each year get cervical cancer but the cost of the vaccine is so high that it is disproportionately spending resources on a cancer that is no longer a big problem.  But, as the pro side points out, it is not just cervical cancer in the total cost. HPV causes ( and costs) for all the following:
    •  genital warts ( 50 per cent of all sexually active people get it) - it can take multiple trips for docs to burn off the warts.
    • recalls of PAP tests
    • Colposcopies ( viewing the cervix)
    • Cone biopsies of precancerou cells
    • treatments of displasia ( - freezing, buring, cutting away the cervix) all in the pre cancer stage.
    • other cancers likely caused by HPV ( penile, anal, oral and esophageal, vaginal and vulvar -- although low in numbers, collectively significant.)

Despite the PAP test and the huge drop in cervical cancer, world wide cervical cancer remains the second most common malignant disease in women. In third world countries it is still the leading cause of death for women. In developing countries like Africa and South East Asia, where PAP screening is deplorable, the HPV vaccine may make a huge impact in protecting women and saving lives.

In the Western world, HPV vaccine provides very high rates of prevention for at least 8 years post vaccine, preventing women from getting cancer in the first place. Why in this day and age, when a vaccine has been proven safe enough and effective for the years when girls are most at risk, would we be arguing that waiting for cancer to strike and then spending all sorts of resources to find it is the more logical option?

( Perhaps look at the vested interests in the systems at work in finding the cancer.)

And note, some of the objections to the HPV vaccine is actually moralistic religious view points, hiding behind "scientific" argument. That moralistic view ( as seen in the parents interviews) has at its basis that sex with less risk is inherently wrong and that teenage sexuality must be discouraged and must have its negative outcomes. That, to me explains, why the Catholic diocese in Vancouver has advised parents not to let their girls have the shot. It is not science folks, its morality.

Me, I know my teenage girls will be exploring with sexuality. It is human. I want them to do so safely.

 But don't just listen to me -- after 7 years of reading about this, I am very firmly in the pro camp. Read the literature yourself at www.ncbi.nlm.nih.gov/pubmed/

 

Posted on Friday, October 9, 2009 at 12:34PM by Registered CommenterAnne | CommentsPost a Comment

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