Tragedy in the UK

Last week I presented the safety study for the Gardasil qHPV vaccine, after this a reader remarked that it was a relief to see as she was concerned by a story she had read. It revolved around the unfortunate case of a UK school girl who died shortly after receiving a vaccine. As the full story does not yet seem to have been covered adequately by local news I thought I would cover the salient points here.

Firstly there are two competing HPV vaccines in the world market, Gardasil produced by Merk and Cervarix made by GalaxoSmithKline (GSK).  Here in New Zealand we have opted for the Merk version of the vaccine while the UK uses GSK’s product. Cervarix immunizes against the HPV strains 16 and 18 which are implicated in development of cervical cancer while Gardasil also covers strains 6 and 11 which cause genital warts.

Thus the first point to be made in relation to New Zealand readers is that the vaccine this young girl was exposed to is not the same one that is being given to our population.

To summarize the facts about this case, as reported by TimesOnline on the 29th of September, 14 year old Natalie Morton died in hospital on the afternoon of the 28 of September. Preceding her death by several hours was her injection of the GSK HPV vaccine Cervarix, this proximity in time is the only evidence that linked the vaccine to the girl’s death.

Late on the 29th the news that Natalie had a “serious underlying medical condition” was reported in the Guardian. At this point it was still unclear (to the public) whether the vaccine was in any way related to Natalie’s death. Health officials were however preparing to continue the vaccinations that had been put on hold following Natalie’s perceived complications.

By the 2nd of October the full story was clear, as covered in Medical News Today, Natalie’s death was revealed to have been caused by a previously undiagnosed and apparently asymptomatic malignant tumour in her chest. The tumour was described as having heavily infiltrated her heart and gone into her left lung. The HPV vaccine was officially cleared of any causitive agency in her death, in fact according to Dr Caron Grainger, Joint Director of Public Health for NHS Coventry and Coventry City Council, it could have happened at any point.

This story, if the end had been less definitive, could have been a very powerful anecdote against the use of HPV vaccines, as comments both within and about the early news stories reveal. Some with a vested interest of discrediting vaccines will undoubtedly still try to use it as such, already there are attempts to label the cause of death as fiction.  This shows a deeply unsettling conspiracy mindset as well as disrespect to Natalie and her family in trying to use her tragic tale to further their own agenda.

Gardasil Post-licensure Study

Last month the Post-licensure safety study for Gardasil (the HPV vaccine) was released. The study focused on the reports of adverse events as reported to the VAERS database by the manufacturer, doctors and patients or caregivers. Much has been made by detractors of the vaccine about the serious alleged side effects that have struck young women given the course of injections. These allegations have been supported by referring to the VAERS database itself so if they are valid they should be upheld by this study.

Of the 12,424 reports that VAERS received in the 2.5 year period following implementation of the vaccine, 772 (6.2%) were classified as “serious”, the total number of vaccine doses distributed in this period was 23 million. The category of “serious” was defined according to the FDA regulatory definition of an adverse event that “is life threatening; results in death, permanent disability, congenital anomaly, hospitalization, or prolonged hospitalization; or necessitates medical or surgical intervention to preclude one of these outcomes”.

It must be noted at this point that the VAERS database cannot determine causality, the events reported merely have to occur after vaccination takes place. Therefore anything that happens to a patient in this time frame that someone thinks might be related to the vaccine may be entered. I point this out only to remind that while we may be looking at vaccine safety life does go on, accidents happen and co-incidences occur. The point of a study such as this is to determine if these events are occuring at a frequency higher than what we would expect in the normal population. In other words, is there really a correlation between these events and the vaccine or is is simply a statistical fluke.

The study looked into each type of adverse report in detail and attempted to answer the above question, does the rate of reporting exceed that which would be expected in the general population? In almost all cases the answer appears to be “No”, the exceptions to this were reports of syncope (fainting) and venous thromboembolic events (blood clots), this finding will certainly be followed up in future studies. Curiously one of he more prominent adverse effects that has been concerning many on both sides of the debate, Guillain-Barre´ Syndrome was not found to occur more than expected.

Guillain-Barre´ Syndrome is an auto-immune condition that can be brought on by vaccines but also by normal infections. The syndrome is caused when the immune system is stimulated by an antigen but then starts to target the body’s own nervous system, it usually exhibits as an ascending paralysis noted by weakness in the legs that spreads to the upper limbs and the face along with complete loss of deep tendon reflexes. As vaccines are made to induce an immune reaction the link between vaccines and the syndrome is biologically plausible and not controversial in the medical community.

The study concludes favourably but cautiously, as scientific studies are wont to do:

Vaccination with qHPV has the potential to decrease the global morbidity and
mortality of HPV-associated diseases, including cervical cancer. After hepatitis B vaccine, which can prevent liver cancer, qHPV is only the second vaccine licensed with an indication to prevent cancer. The postlicensure safety profile presented here is broadly consistent with safety data from prelicensure trials. Because VAERS data must be interpreted cautiously and cannot generally be used to infer causal associations between vaccines and AEFIs, postlicensure monitoring will continue, and identified signals may be
evaluated using epidemiologic observational studies.

The full study can be found here, a summary of the study here and a comprehensive discussion of the study here.

VAERS Data: A Comparison

My two regular readers are probably sick to death from hearing about a certain HPV vaccine by now but I thought I’d put up a quick comparison of VAERS data for those that are interested.

The raw VAERS data is quite popular among those who wish to cast aspersions on the safety of the vaccine so I thought I would query the database myself to see what the results would be and compare the Gardasil figures against less controversial vaccines. I decided to compare the data for all reported adverse events between the time 2006-2009 for not only the HPV quadrivalent vaccine but also the flu vaccine and the MMR vaccine. If Gardasil is so dangerous the figures should be significantly higher for this vaccine than the others shouldn’t they?

Gardasil Follow-up: The Evil Toxins

My last post on Gardasil has garnered quite a bit of interest so I thought I would follow it up with a look at some of the other claims about this vaccine that are also geared towards warning women away from it. The focus of this entry is, as the title implies, the ingredients of the vaccine and their alleged toxicity. Now I would first like to make clear that I am not trying to argue that these compounds are not at all toxic, that would be an untenable position almost anything is toxic at the right (or wrong) dose. This brings up the heart of the issue though, the dose is key here, the claims by detractors of the vaccine imply that the amounts of the chemicals in the vaccine are above the toxic threshold. I, along with the medical community so I feel I’m in good company, consider this to be an incorrect conclusion.

Gardasil

(Edit: For those interested in the toxic components of the vaccine please look here.)

Recently I  read a letter in a New Zealand paper decrying the widespread acceptance of the new HPV vaccine Gardasil. The letter contained references to suitably scary statistics from a impressive sounding report, in it it was claimed that Gardasil had contributed to the deaths of 18 people and had over 8000 reports of harm due to the administering of the vaccine. The letter ended with the sentence “This vaccine is essentially a large-scale, public health experiment. With doubt about its safety and efficacy, my daughters will not be getting it.”  I thought it might be useful to provide some information that casts a little more light on the situation, the statistics used in the letter and information on efficacy.

Pseudoscience

Science and pseudoscience, what’s the difference? It’s not a trick question, as you approach the cutting edge of science, where the known becomes the unknown and theories become wild and speculative the line between the two can be quite fuzzy. String Theory anyone? But in general the difference lies in that where science starts with facts and observations and arrives at conclusions pseudoscience starts with a conclusion and twists fact and observation to fit. The two most common avenues to pseudoscience appear to me to be: First, when a hypothesis is retained long after dis-confirming evidence should have rendered it obsolete. Adherents of the “Vaccines cause Autism” movement would fall into this category. Second would be those who attempt to prove their own pet ideology by either conducting flawed research or by willfully misinterpreting the work of others. Creationists and Intelligent Design proponents might fall into this category.

Correctly discerning pseudoscience can be difficult, especially if it appeals to our own biases. Some things to consider are: Arguments from authority, real science shouldn’t be decided by a chosen few, rather it is the sum total of a multitude of efforts and advancements are evaluated by the scientific community as a whole and finally a consensus is reached. Insufficiently detailed references to supporting data, it is important to be able to find the primary sources that are being used to support a position so that you can read it yourself and determine if it has been correctly interpreted. Reliance on testimony, look at the quality of the references used, if they come mainly from personal experience they may not be reliable.

Finally, you may want to look at a larger sampling of the scientific community and see what they have to say about the topic or person you are interested in. There are bound to be many sides to the issue but you may pick up on the general flavour of scientific opinion. Good luck and happy investigations.

Resources

http://www.theness.com/articles.asp?id=30

http://www.uwgb.edu/dutchs/pscindx.htm

Vaccines

Parents have a tough job. That’s a fact. However this job is made tougher by two things, 1. Fear for their children’s safety, 2. False information in the media. The first is completely natural and even necessary. The second unfortunately is also natural and is something that arises because of peoples fear.

Part of the reason is that when you are talking about someone’s child then any risk is too much. That is understood and absolutely forgivable, this leads to trouble though when that fear is misinformed and the public does not have the knowledge to decipher the facts for themselves. An inability to rationally weigh the risks also leads to making decisions that can be detrimental to health long term.

The trouble with the current concern over vaccines causing autism is that this is primarily a case of parents being overwhelmed by media coverage that is intended to produce ratings not provide accurate information. It is a recurring theme that the controversial stories are hyped and the factual follow ups are down played or overlooked altogether.

Multiple studies have shown that the putative link between the MMR vaccine and autism does not hold up, some of these are listed below. In addition the rise in autism diagnoses that anti-vaccination groups point to is widely regarded by the scientific community to be an artifact of the inclusion of a wider variety of disorders under the umbrella term of “Autism” in recent decades. Autism is defined by a certain constellation of symptoms being present and their severity. In recent years less severe examples of these symptoms have been added to the diagnosis of the autism spectrum. This allows for a greater number of diagnoses than in the past.

This is a very complex and emotional debate and I have only touched on it briefly here, I recommend reading up on the subject through the resources listed below.

Resources

http://www.cdc.gov/od/science/iso/mmr_autism.htm

http://www.theness.com/articles.asp?id=74

http://www.theness.com/neurologicablog/?p=37http://www.immunize.org/mmrautism/

http://www.immunize.org/catg.d/p2065.htm

http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=26561

http://www.bmj.com/cgi/content/full/330/7483/112-d

http://www.bmj.com/cgi/content/full/324/7334/393