Bumbleymummy,
'RW, my comment about under reporting was in response to her comment: "They will say that doctors wont admit there are any side effects to vaccines.
But the side effects are well known, and except in very rare cases quite mild."
That was why I mentioned under reporting in relation to vaccines.'
Well Jennifer Raff is talking about vaccine side effects. Now vaccines are extremely thoroughly tested before being licensed. I will happily admit that my view of this aspect of vaccines will be coloured by the fact that my daughter was part of a vaccine trial. The way we, as a family, were treated by the group conducting the trial was absolutely brilliant. I have no way of knowing if every baby enrolled in such a trial is treated as well, but it was extremely impressive. And they did want to know about absolutely anything that might even possibly be a side-effect. In fact they wanted to know some stuff which was clearly quite impossible to be related to the vaccines, because they took a very cautious approach. This is clearly the sort of thing that goes on before a vaccine is licensed for use. To quote:
"Many steps occur to assure the safety of vaccines--starting with laboratory testing, animal studies, and several phases of clinical testing in humans."
www.vaccinesafety.edu/VAERS.htm
As the quotes in my earlier post point out vaccine testing is actually more rigorous than for other drugs. Clinical trials for vaccines will involve more individuals, for a start. Which makes it more likely they'll pick up any adverse reactions:
"Phase III Vaccine Trials
Successful Phase II candidate vaccines move on to larger trials, involving thousands to tens of thousands of people. These Phase III tests are randomized and double blind and involve the experimental vaccine being tested against a placebo (the placebo may be a saline solution, a vaccine for another disease, or some other substance).
One Phase III goal is to assess vaccine safety in a large group of people. Certain rare side effects might not surface in the smaller groups of subjects tested in earlier phases. For example, suppose that an adverse event related to a candidate vaccine might occur in 1 of every 10,000 people. To detect a significant difference for a low-frequency event, the trial would have to include 60,000 subjects, half of them in the control, or no vaccine, group (Plotkin SA et al. Vaccines, 5th ed. Philadelphia: Saunders, 2008)."
So they're actively searching out possible side-effects at this stage of development. And any possible side-effects must legally be recorded.
So the vaccines in question will have undergone considerable testing before they come to be used by the general public. This is why before vaccines are even used by people not enrolled in clinical trials it is reasonable to put some figures on the frequency of some side-effects. The pack inserts for the vaccines list these side-effects, and doctors or other health care professionals administering vaccines should be aware of them and tell you about them. I have never had any problem with individuals administering vaccinations to me or my children denying that they have side-effects which we know about. But as Jennifer Raff says they're generally quite mild. Just to pick a vaccine at random, the MMR has the following recognized side-effects:
www.nhs.uk/Conditions/vaccinations/Pages/mmr-side-effects.aspx
No one is denying these, or I would seriously hope they're not.
So all of this happens before the vaccine is licensed. Then it (if it's safe and effective and cost-effective etc.) will get licensed for use. Sometimes manufacturers will do Phase IV trials, but let's presume not. Then, the vaccine starts being used. Hopefully by this point the main side-effects will have been identified and only those not detected in the populations used for the trials will be those that are so rare that the numbers used were not large enough to detect them. Or as this handy page points out:
"...adverse events occur in less than one per 20,000 vaccinations, it is possible that none will be detected before licensure.
Individuals in subgroups, such as those with certain medical conditions, may not have been represented in the prelicensure trials.
The numerous possible combinations of vaccines (as well as drugs and biologics) that may be concomitantly administered with the new vaccine may not have been represented in the prelicensure trials."
Sometimes this does, obviously, happen. Which is where the post licensing monitoring comes into effect, and atthis point the possible issue of under-reporting becomes an issue. I've been doing a certain amount of reading to understand how much of an issue this will be. Because there is, indeed, under-reporting of adverse effects in general. The numbers from studies vary very widely. You quoted earlier in the thread from here: www.cs.berkeley.edu/~daw/teaching/c79-s13/readings/AdverseDrugReactions.pdf
Which is about all drug adverse reactions. We are specifically talking vaccines here, so a paper like this one might be relevant:
archpedi.jamanetwork.com/article.aspx?articleid=517131
But the above is all about a vaccine with a very serious side effect, so the very low rates of under-reporting aren't perhaps applicable across the board.
Also vaccines are subject to scrutiny not given to other drugs. There is, for example VAERS:
www.vaccinesafety.edu/VAERS.htm
The link above discusses under-reporting and over-reporting amongst other issues.
This paper discusses one side effect and VAERS:
aje.oxfordjournals.org/content/154/11/1006.full
It does seem from my reading that the more serious the side-effect the more likely it is to be reported (I would suppose this would come as a surprise to no-one). The more serious effects however can potentially be under-reported too, and this is the more worrying situation.
What does the history of vaccines tell us about rare serious side-effects being picked up after the vaccine has been licensed? There have cases, most recently I would suppose the narcolepsy link with H1N1 vaccination springs to mind:
www.hpa.org.uk/NewsCentre/NationalPressReleases/2013PressReleases/130227Pandemicflunarcolepsy/
In this case:
"This suggests a risk of narcolepsy following vaccination with Pandemrix of around one in every 55,000 doses of the vaccine."
This was a side-effect initially picked up upon in Sweden and Finland, and led to studies in the UK identifying a similar pattern here in the UK:
"In conclusion, we found evidence of an increased risk of narcolepsy in children who received pandemic A/H1N1 2009 influenza vaccine (Pandemrix) in England. Despite attempts to minimise ascertainment bias, the potential for overestimation of risk remains because of more rapid referral of vaccinated patients. Long term follow-up of the cohorts exposed to the vaccine is needed to properly evaluate the attributable risk."
www.bmj.com/content/346/bmj.f794
Which shows how the issue of vaccine safety has become very global in nature. Which is I would hope you'd agree a good thing? Whilst you may feel the Yellow Card System in this country is under-publicised, systems such as VAERS are certainly well known. There are also global initiatives like:
www.who.int/vaccine_safety/initiative/en/
So, apologies for the long post. I agree with Jennifer Raff that vaccines have well documented and mostly mild side-effects. There are rare more serious side effects, but clinical trials are designed to try to identify these too. There may, as with the narcolepsy example above, be side-effects that do not get picked up upon, but these seem to be rare where serious. The global nature of vaccine monitoring is a positive aspect of today's globalisation. Admittedly there must be unknown side-effects which are not picked up on in trials, and escape notice from all the systems which are in place. But these are by their very nature hard to quantify. I suppose my conclusion is that there are side-effects from vaccines. Generally these are well recognised and characterized. The commoner ones are mild. There are more serious side-effects which we are again aware of that have been identified from clinical trials. Sometimes rare serious side-effects won't be identified in clinical trials, but the monitoring systems in place and the global nature of information in today's world abet the identification of these. If a vaccine causes an unrecognised side-effect then that side-effect might be mild and/or self limiting. In this case if it goes unreported then the impact is low. More serious side-effects would clearly need treating, and hopefully if the causal nature between the vaccine and the effect in an individual case was unrecognised and/or unreported this should be no barrier to effective treatment. The problem in this case would be that the side effect would not become associated with the vaccine as soon as possible. Such side-effects would mostly be detected in trials, but clearly this will not always be possible. The evidence appears to be that serious side-effects are reported with a higher rate than lesser ones, and that the systems in place are capable of detecting even rare side-effects. So, despite the fact that side-effect reporting isn't perfect I am failing to see this would lead me to disagree with Jennifer Raff when she writes:
"They will say that doctors wont admit there are any side effects to vaccines.
But the side effects are well known, and except in very rare cases quite mild."
Anyway, I'll stop there for now.
Cheers,
Rosewind