VACCINE DEBATE:The arguments for and against the cervical cancer vaccination programme
NO
Gardasil has never been proven to prevent cervical cancer, hasn't been sufficiently tested on the target age group, and not enough is known about adverse reactions, writes PAULA BYRNE
MOST PARENTS will do anything to protect their children. The idea that I could protect my little girl from cancer down the road is pretty compelling. This is the scenario with which we are presented by the makers of Gardasil, the vaccine purported to prevent cervical cancer.
However, the reality of this vaccine is far from straightforward.
Cervical cancer is relatively rare, with approximately 3.9 deaths per 100,000 people each year in Ireland. There is no epidemic to warrant the urgent introduction of this vaccine.
Cervical screening (pap screening) has been a public-health success. Deaths from the disease reduced by 70-80 per cent from 40 years ago due to more of these cancers being caught early. Most deaths nowadays are in women who did not get pap smears. So surely more investment in the screening programme is better use of public funds.
There are, as the old saying goes, lies, damned lies and statistics, and one would need to carefully study the clinical trials to understand how this vaccine is being framed as something that prevents cervical cancer when the reality is quite different.
The theory behind the vaccine programme is sound. There is a virus called Human Papilloma Virus (HPV), which is associated with cervical cancer. If we can prevent HPV infection, therefore, we can presumably prevent cervical cancer.
However, Gardasil has never been shown to prevent cancer, and it is disingenuous to present it as such.
HPV is a very common infection, and it almost always clears by itself. In some cases the virus may persist. These woman may go on to develop pre-cancerous lesions and some eventually cervical cancer, but the relationship between infection at a young age and development of cervical cancer 20-40 years later is, at this stage, unknown.
The vaccination programme here targets 12-year-old girls, but the main Gardasil trials did not enrol girls under 15. There was one small trial of nine to 15 year olds, which involved fewer than 1,200 children. Adverse reactions were higher in this group, and the vaccine manufacturers themselves admit that efficacy in this group was “inferred” because only the development of antibodies in the blood was measured.
This is a moot point, as studies into other vaccines have shown that the presence of antibodies to a particular infection does not automatically provide protection. Whether the vaccine will provide any protection in this age group is unknown.
The trials of Gardasil measured lesions on the cervix, which are not cancerous, only a minority of which will ever become cancerous, and the vaccine was very successful in preventing the low-grade types of these (called CIN1). Current guidelines advise not treating these lesions, as they tend to go away by themselves.
The vaccine was significantly less successful at preventing those lesions (known as CIN3 and AIS) that are likely to become cancerous. It would take decades to find out if these small changes in pre-cancerous states will translate into improvements in the death rates from cervical cancer.
There are at least 15 different types of these viruses that are considered cancer-causing. The vaccine targets the two infections most commonly found in cervical cancer. Screening must continue for cancers caused by the other types of HPV. It seems logical, therefore, that investment in cervical screening and education programmes to raise awareness of the disease would be far more beneficial than vaccination.
A disturbing phenomenon was discovered in the course of the trials whereby those women given the vaccine developed lesions associated with other cancer-causing types of virus in larger numbers than the non-vaccinated. In other words, by suppressing two types, other types eventually filled the biological niche left behind. So, in much the same way as we now have antibiotic strains of bacteria, such as MRSA, because of the overuse of antibiotics, we could simply be replacing one cause of cervical cancer with another.
Adverse reactions to the vaccine were analysed in an article in the Journal of the American Medical Association. Serious reactions to the vaccine were estimated at 3.4 per 100,000 doses distributed. Each person receives three doses, so the serious adverse reaction rate is probably closer to 10 persons per 100,000 doses given. This is almost three times higher than the death rate from cervical cancer in Ireland. These reactions, associated with administration of the vaccine, included deaths, blood clots and various progressively degenerative diseases such as Guillain-Barré Syndrome and ALS.
It is not compulsory to report adverse reactions here or in the US. Under-reporting is a problem. The FDA (the drug regulatory body in the US) estimates that only 10 per cent of vaccine adverse reactions are reported. So rates of life-threatening side effects could be higher than the figures.
SO THEN, we are being asked to vaccinate our daughters with a vaccine – that has never been proven to prevent cancer
– that has not been adequately tested on girls of its target age group
– that may only replace one cause of cervical cancer with another
– that cannot replace screening
– and whose safety gives cause for concern.
Also of some concern are the circumstances in which the vaccine was initially licensed at the US Department of Health and Human Services (DHSS). Researchers at the National Institutes of Health (part of the DHSS) patented the technology that provokes Gardasil's immune reaction to HPV and licensed its technology to the vaccine manufacturer. This involvement is declared by the two scientists involved, Lowy and Schiller, in an article published in the Journal of Clinical Investigationin 2006.
The trials that led to the vaccine being licensed were called FUTURE I and II, and the Journal of the National Cancer Institutepublished a review of these in 2010. According to this review, the 38 researchers involved received payment from the manufacturers in various forms, usually as consultancy fees.
In a study in the Journal of Contemporary Clinical Trialsin 2008, it was established that when a pharmaceutical company funds drug trials it is more likely that the trial results will be favourable to the drug in question.
Proliferation of cervical cancer awareness conferences and campaigns seem to have pushed the Gardasil vaccination up the political agenda.
In common with many other drugs and vaccines, some scientific and patient groups have promoted information on the issue with financial assistance by the manufacturer, according to an article by Rothman and Rothman, published in the Journal of the American Medical Associationin 2009. The same article says that, in some cases, the financial support has been indirect, so patients are unaware that expert advice has been at least partly paid for by the vaccine manufacturers.
This vaccination policy is based on presumptions: the presumption of life-long protection of the vaccine, that the vaccine has the same effect on adolescent girls as on older women, that no replacement of cancer-causing strains of HPV occurs, that the vaccinated women continue to attend screening programmes, that natural immunity to HPV is unaffected, and that the side effects are worth the risk.
More long-term studies would be required to answer these questions, and the real value of vaccination with Gardasil will not be known for decades.
Most of all, further unbiased research must be carried out, free from possible conflicts of interest and over long periods of time to establish efficacy. Until then there is good reason to exercise caution.
Paula Byrne is a therapeutic radiographer and homoeopath who has researched Gardasil
YES
The vaccine has been fully tested and will protect women from the most common forms of HPV-related cancer - and it is free, write
DR DARINA O'FLANAGANand
DR BRENDA CORCORAN
EACH YEAR in Ireland about 250 women are diagnosed with cervical cancer, and 80 die from it. At least 70 of these cases are linked to Human Papilloma Virus (HPV).
We now have a new vaccine to protect women from the most common forms of HPV-related cancer. From September, the HSE will offer a safe, fully tested HPV vaccine called Gardasil to every girl in the country who is starting first and second year in secondary school. It will then be offered to all future first years.
The vaccine is free, and international studies have shown that vaccinated women are less likely to become infected with HPV, and are therefore less likely to develop cervical cancer. Australia has already seen a reduction in genital warts, a key indicator of HPV, since vaccine was introduced.
The HSE programme, which will be mostly school-based, aims to achieve a high uptake of more than 80 per cent for the vaccine. Each girl will need three doses of the vaccine over a six-month period, which will substantially reduce their risk of developing cervical cancer as adults.
In Ireland, 1.68 million females aged 15 and older are potentially at risk of de- veloping cervical cancer, the eighth most frequent type of cancer among women here, and the second most common among females aged 15-44. Worldwide, cancer of the cervix is the second most common cancer among women, with more than half a million new cases and 274,883 deaths reported in 2008.
Ireland is one of many countries that is offering protection against HPV- related cancer. Although the vaccine is relatively new, all the evidence has shown that it is safe and effective. The World Health Organisation monitors and reviews the safety of HPV vaccines. By March 2009, more than 60 million doses of HPV vaccine had been distributed either as part of national immunisation programmes or by private doctors, without raising any significant issues.
Gardasil has a good safety record. It has been tried and tested in large clinical studies that lasted more than a decade and included more than 25,000 subjects in 33 countries. The most frequently reported adverse events were local redness and/or swelling at the point of injection, and fever. These are typical, and usually mild and temporary reactions to any vaccination.
While these reassurances are welcome, the collection of high-quality data on the vaccine from different geographical locations and epidemiological settings is ongoing. As with all vaccines, there is extensive surveillance in place for Gardasil to detect any unusual and unexpected events. Surveillance is carried out by the manufacturer, and also independently by the Irish Medicines Board. The effectiveness of the vaccines is also being monitored.
Infection with HPV is common. Most people will get at least one infection, which can be in active or dormant form, during their lifetime. The virus infects the skin, and mucous membranes of the upper respiratory and genital tract. There are more than 100 types of HPV, and some types are easily recognisable, such as the ones that cause common warts that might be found on a person’s hands. About 40 types can infect the genital tract. Some of these are low-risk types, while others are high-risk and associated with various cancers such as those of the cervix, vulva, vagina, anus, penis and throat.
About 11 per cent of women in Ireland are estimated to be infected with cervical HPV infection at a given time. More than 70 per cent of Irish women developing cancer are infected with a high-risk type (16 or 18).
Worldwide, 71 per cent of invasive cervical cancers are attributed to HPV types 16 and/or 18, both of which can be prevented by the new vaccine. There is increasing evidence linking HPV with cancers of the anus, vulva, vagina and penis. Between 15 and 20 per cent of head and neck cancers are associated with HPV. Although these cancers are much less common than cervical cancer, their association with HPV means that preventative strategies similar to the one for cervical cancer could be used in the future.
As the HPV vaccines protect against only 70 per cent of cervical cancers caused by the HPV types included in the vaccine, it is important that girls vaccinated in the HPV programme avail of smear testing offered by the Cancer Screening Service through Cervical Check (cervicalcheck.ie) when they are older. This screening, via smear tests, will help detect problems that arise from other types of HPV, allowing them to be identified and treated before they develop into invasive cancer. Countries with cervical cancer screening programmes in place have seen a marked decrease in cervical cancer.
Like Ireland, every one of the many countries implementing HPV vaccination programmes are doing so in the best interest of their citizens to maximise health, prevent disease and prolong life. In Ireland the proposed HPV vaccine has been assessed by the Health Information and Quality Authority (HIQA), and is considered to be a cost-effective health intervention. Around the world a failure to implement a HPV vaccination programme would be considered a withholding of potentially life-saving preventive treatment.
Dr Darina O’Flanagan is director of the Health Protection Surveillance Centre. Dr Brenda Corcoran is consultant in Public Health Medicine at the HSE National Immunisation Office
More information on the HSE HPV vaccine programme is at hpv.ie