Changing vaccines: a ‘foolish decision’

As I mentioned before, there are two vaccines for the ‘cervical cancer’ virus, HPV – Cervarix and Gardasil. But why do some countries choose one over the other? And how do these decisions get made?

As you can see from this cervical cancer research timeline, studies about a possible HPV vaccine started in the 1990s.

In the UK, once the vaccines were proven safe and effective, the Joint Committee on Vaccination and Immunisation looked at the evidence and made its recommendation to the Department of Health in 2008. As a result, the government decided to use Cervarix in their screening programme. But following a debate on whether the NHS should replace Cervarix with Gardasil, it seems that the committee might have to go through the whole long-winded procedure all over again.

To find out more about what should happen next, I spoke to Dr Anne Szarewski – a clinical consultant at Cancer Research UK’s Centre for Epidemiology, Mathematics and Statistics at the Wolfson Institute of Preventive Medicine.

You can listen to our conversation below – but these are the main issues that Dr Szarewski raised:

Given that the vaccination programme is only just being rolled out, switching now would prevent us from comparing the effectiveness of each of the vaccines. Therefore, “the government would be foolish to change at this point”.

Similarly, a country needs to decide whether it is more important to prevent cervical cancer with a greater protection or to prevent genital warts and cervical cancer with less protection for the latter. “Cervarix offers much greater protection against cervical cancer than Gardasil does because it has a lot of cross-protection against other high-risk HPV types that are actually not included in the vaccine,” says the expert.

There are countries where culture and religion affect this decision. As Dr Szarewski says, “what’s going to work for example in a Muslim society is not likely to be the same in ours.”

Therefore, she believes Cervarix tends to be more popular in conservative countries. Vaccinating a woman against a sexually transmitted disease in those countries is “alien”, says the expert. Why would you vaccinate women against genital warts when they are supposed to have one sex partner their entire life?

Additionally, a country’s infrastructure determines the effectiveness of a vaccination programme. Without good transport and call-recall systems, which ensure that girls are given the jabs at the right time, women will not be looked after appropriately.

And finally, “the pharma industry of course is involved but ultimately it is the Department of Health that has to make the decision.”


Understanding policy over vaccination

The fight against cervical cancer can begin as early as the age of 12.

In September 2008, the UK National Health Service (NHS) started a national programme to vaccinate girls aged 12 to 13 against the human papillomavirus (HPV).

But the UK is just one example of how the discovery of a vaccine leads to a national vaccination programme. In fact, not all countries have invested in one. Those who did, may not have chosen the same vaccine. And also the way vaccination programmes are designed can differ – concerning the age vaccines are taken, the price paid by the governments and whether all those covered by the programme actually have access to the vaccine.

There are two vaccines that can protect against cervical cancer: Gardasil and Cervarix.

The Gardasil vaccine was created by German pharma company Merck, and was first approved by the US Food and Drug Administration (FDA) in 2006. Although it does not prevent all types of cervical cancer, Gardasil protects against four types of HPV: two of them (16 and 18) cause most of cervical cancer cases; the other two (6 and 11) are responsible for 90 per cent of genital warts cases. It is given as three injections over six months (if starting in January, the second would be given in March and the third in June).

The Cervarix vaccine was created by the UK’s GlaxoSmithKline (GSK) and licensed by the European Medicines Agency (EMEA) for use in the UK in 2007. Cervarix protects against HPV types 16 and 18. Like Gardasil, it is given as three injections over six months, but in different times (if starting in January, the second and third ones would be given in February and June respectively).

Nevertheless, this brief description of both vaccines is not enough to judge the effectiveness of each one nor the reasons that lead certain countries to choose one or the other. Some issues should be considered when comparing both vaccines:

– HPV is not only responsible for cervical cancer, but also for other types of cancer (such as neck, anal, penal, head) as well as genital warts;

– Being a sexually transmitted virus, HPV is a taboo in rather conservative countries;

– A vaccination programme is only effective with an effective calling system (i.e every person covered by the programme receives an invitation) to ensure that the three vaccine doses are taken appropriately;

– Vaccinating girls will affect how often they need cervical screening later in life, so the information given to both children and parents needs to be clear and accurate;

–  Although the evidence on vaccinating young girls is relatively clear-cut, research has not yet shown whether the uptake of the vaccine by young adults is effective, appropriate, cost-effective – or even harmful.

You can find more information on HPV vaccines here.

Cancer experts have kindly agreed to talk to me about some of these issues and I will soon be sharing their thoughts here. In the meantime, please feel free to share your experiences and doubts. The same experts might be able to answer your questions. How much is known about the vaccination of cervical cancer in your country?

Cancer Research UK

Video: What cervical cancer is about

This video helps understand the main issues that this project aims to investigate. I spoke to Professor Jack Cuzick from Cancer Research UK, who highlighted the importance of changing cervical screening methods and the understanding of the human papilloma virus (HPV). I also heard the opinion of three women in the streets of London.

Video Transcript:

Débora Miranda: According to the World Health Organisation, over 12 million people are diagnosed with cancer every year. Two in five cancers are potentially preventable. The Human Papillomavirus or HPV causes cervical cancer, and is the second biggest cause of female cancer mortality. There are two main weapons against the disease. Screening for cervical cancer, which has been widespread in developed countries for many years, and newer techniques aimed at the virus that causes the disease.

Prof Jack Cuzick: There clearly is not very much understanding about the human papillomavirus. I think most people know that they should get screened and get an invitation. There has been a drop in acceptance of invitations in younger women. There is a lot of misunderstandings and fears about the virus because it is a sexually transmitted virus and it raises all sorts of issues about behaviour and partners behaviour which need to be handled with quite sensitively so doctors and people in general do need to understand more about this virus. It’s a very common virus. Like the common cold in most cases it leads to very minimal changes.

Voxpop 1: I’m not one of those organised people who makes a note of when the next smear test should be. I wait to get a letter from my GP or from the hospital.

Voxpop 2: When I got the letter I didn’t read it that well. I just sort of knew that I had to go. My friend had recently got a letter because she had just turned 25 as well, so we decided to book our appointments for the same day so we could both go to the doctor surgery together. That was quite nice to have the moral support. And even though I didn’t read the letter that much the nurse was really nice and she explained everything really well. The whole experience was much better because of that.

DM: Different countries implement different cancer screening programmes. It is important to understand the scientific evidence on which worldwide governments are based to make their decisions.

Voxpop 3: I grew up in another culture, where you get a yearly smear test if you’re on the pill. When I was in my early twenties I was taking the pill and so I would have the test every year and that was part of the culture. I grew up in the south of France and I think people are probably a bit more laid back about their sexuality or anything which involves your body It’s not seen as a taboo as maybe in an Anglo-Saxon culture.

Voxpop 1: I think it’s become better since there’s been so many high-profile cases. And I think Jade Goody’s case really brought to the general population the importance of testing and that it can happen to you at a very young age.

JC: The most important thing in screening programmes (and it’s been clearly demonstrated in cervix cancers) is high coverage. Screening can only work if people that can be screened do it. The coverage is very very important. The second most important thing is having an effective test and we’re seeing now that the HPV testing is more effective, more sensitive than cytology. So we do need to move to HPV testing as a method of screening.

DM: Cervical cancer raises controversial questions. Why does the age to start screening change from one country to another? Is there enough information about the vaccine? And what are the harms of screening?

JC: As with all screening there may be some harms. The main harm associated with cervical screening is, there is increasing evidence now that the treatment associated with lesions at a young age leads to increase miscarriage, early pregnancy rates because you basically have to loop out a piece of the cervix and that makes the cervix weaker.

DM: But before these questions are answered, follow the advice:

Voxpop 2: It wasn’t pleasant, I don’t think it would ever be pleasant to have that sort of thing but it was fine. It’s uncomfortable but it’s five minutes of your day compared to possibly the rest of your life if you catch something early. It’s a necessary evil but it’s really not that bad.

The key cervical cancer questions

These are some of the main questions I aim to investigate:

  • What is the incidence of false positives and unnecessary treatment for cervical cancer?
  • What is the difference between the Gardasil and the Cervarix vaccines?
  • Should men be vaccinated?
  • Are there any cervical screening programmes running in Africa?
  • Is it cost effective to run screening and vaccination programmes in tandem?
  • What is the scientific evidence that governments are based on to implement cancer prevention programmes?
  • What is the link between HPV and other types of cancer?

Feel free to add any questions.

Picture courtesy: Jan Christian, Creative Commons

Opening the discussion

The Cancer-Screening project is now open to your thoughts. Whether you want to comment on my interviews with experts, to ask questions about the presented data or to share your own experiences, make sure you write it down.

If you would rather not write your comments in English, you can do it either in Portuguese, German, French or Spanish, and I will make sure they are accurately translated.