By Alison Campbell 08/07/2019

New Zealand’s measles outbreak keeps on ticking along. So do the media stories about it. (The FB posts associated with each article aren’t moderated and I suspect this is partly because they generate so many clicks.)

A couple of days ago, TVNZ’s Breakfast show carried an interview with a doctor, on the importance of Gardasil, a vaccine that offers protection against several strains of HPV (Human Papilloma Virus). This virus is causally implicated in the development of cervical cancer, genital warts, penile & anal cancer, and some cancers of the mouth and throat. So anything that can reduce rates of infection with the virus will have an impact on the rates of these cancers further down the track. The news story came on the heels of a new paper (summarised here): a meta-analysis of research on Gardasil’s effectiveness that shows significant drops in rates of HPV infection in the vaccinated cohorts.

Anyway, as you might expect, the anti-vaccine activists are all over the story’s FB post. And thus it was that I was alerted to a new “study” by an Italian group, Corvelva, which purports to show that Gardasil contains a number of contaminants, including foreign DNA. (You’ll see why I wrote “study” shortly.)

Now, Corvelva has “published” several documents setting out their findings¹. I say “published”, because as far as I can tell their reports exist as on-line pdfs only. That is, they haven’t been through even the rudimentary peer-review process associated with bottom-tier journals, such as those in the OMICs stable. Rather surprisingly, the document hasn’t listed the names of those who wrote it.

The document leaps straight into their results, and yes, up-front they look alarming. The Corvelva group claim to have found both DNA and RNA, from a wide range of sources, as contaminants in the vaccine.

However, it’s not obvious that they used controls in this study. So there’s no way of telling whether or not there were any external contaminants present e.g. DNA shed by workers in the lab. Certainly a lot of the contaminants they claim to have found in their Gardasil samples are from bacteria that are part of the human microbiome, and without proper controls it’s not possible to draw conclusions about where they came from. (There’s a discussion about the nature of appropriate controls here.)

There is no statistical treatment of the results.

There is no discussion – that important section of a report that puts the findings in context, and relates those results to those of other workers in the field. Come to that, there’s no attempt to link to relevant research literature at all, just a very scanty (N = 3) “Bibliographic references” section that relates to sequencing techniques. Heck, they even say things like “see research by Prof. Lee”, but provide no citation at all²! Honestly, if a first-year uni student submitted a write-up like this they’d get a big fat F for it.

Anyway, I said all this (albeit more briefly) on that particular thread on the Breakfast story. (Plus some comments on other statements by the same individual.)

The response (below, & I’m leaving it complete given it was made on a public page) rather effectively reinforced my impression that many anti-vaccine activists plague enthusiasts really don’t understand the scientific research process at all.

Suuuure I’m denying “inconvenient science”, Karen³.


¹ The Skeptical Raptor has had a more detailed look at Corvelva’s output (see here, for example).

² Although, I have my suspicions as to who this might be.

³ Karen mentions “the BMJ article just published that speaks to the clinical trials and how adverse events were minimised or ignored”. She helpfully does not provide any link to this. (Also, since many BMJ articles – both research papers and editorials – are behind paywalls, I’m not sure if she’s read more than an abstract.) Fairly sure it’s not this editorial, though. But here’s the list of research papers published in the British Medical Journal in May & June this year.


The post “i’ve done my research!” appeared first on BioBlog.

0 Responses to ““I’ve done my research!””

  • Hi Alison,

    I posted a question to Sceptical Raptor to which I have had no response, and I invite you to address it. I think it is fair to question results of the Corvelva study – but then which analysis is the correct one? Do you have ANY laboratory analysis of a vaccine, whether independent or not? In the absence of any alternative, surely the Corvelva study is quite literally the best available?

    I should add, I have had laboratory test results done e.g. for blood samples, and in no case were the results peer-reviewed.

    • The Corvelva study is not ‘the best’ available; it’s not worth the electrons used to spread it around.

      The difference between your personal blood tests & the Corvelva study is that the latter is being promoted in a way that could have a negative impact on public health. Also, if your tests were of concern, a) they’d probably be reviewed by another specialist, & b) you’d have the opportunity to ask for a 2nd opinion.

  • Patrick,

    Just quickly elaborating on your points and Alison’s comment –

    “Do you have ANY laboratory analysis of a vaccine, whether independent or not?”

    Not sure what you’re asking as to my reading it’s lacking context, but you read as if asking if there are any studies at all on any vaccine, but that’d be an odd question given sheer number of tests on vaccines.

    (If you mean tests on contents—you don’t say—they’re done before vaccines are licensed and have to as they’re needed for the licensing, if nothing else. Put it another way, if a vaccine has been licensed, you know the contents have been tested. If you mean something more specific, you’ll have to say — we don’t have ESP or don’t offer cold-reading services! 😉 )

    “In the absence of any alternative, surely the Corvelva study is quite literally the best available?”

    That’s not how scientific papers are looked at. Just because something is published doesn’t necessary mean it’s worth looking at or taking as “truth”. Researchers look at if what is presented can make the claims it does. If it can’t, then it doesn’t matter how many other studies have been published or not, that work isn’t good.

    As Alison was explaining, that study doesn’t come out well of a closer look.

    “I should add, I have had laboratory test results done e.g. for blood samples, and in no case were the results peer-reviewed.”

    Two different things there, the tests and the interpretation of them.

    The tests themselves will have been developed from a lot work, peer-reviewed. They’ll also include recommendations and instructions on how to interpret (“read”) the test; those recommendations will also be peer-reviewed.

    Your doctor isn’t sitting there thinking, “Oh, I’ll just read these like this” — they’re leveraging the ground work lay down by a lot of science (peer-reviewed).

  • Patrick,
    Asking at my local medical laboratory reveals that they have daily internal controls and weekly external controls for each test they perform.

    If the daily controls are not met then the results of the test will not be released. Problem solving occurs until the equipment reads the controls accurately.

    External controls ensure that each laboratory results are comparable to those from other laboratories. If a laboratory does not meet the external controls then their license can be revoked.

    So yes, effectively your local laboratory is peer-reviewed. But then it’s up to the person requesting the test(s) to interpret and act on the results.