Childhood Vaccinations – Necessary or Overkill? Sequal Thread

You do realise that going from 1 in 120 to 1 in 2500 is a decrease in prevalence right Buz? Did you maybe get those numbers a bit mixed up?Of course as was gone into in some detail on the previous thread there are a whole host of factors which suggest that this 'mushrooming' is at least in significant part due to changes in what is classified as being part of the autistic spectrum and a much higher profile for autistic spectrum conditions both among medical practitioners and the general public. So rather than a mushrooming in the prevalence of autistic spectrum conditions what we are seeing is a mushrooming in the identification and reporting of autistic spectrum conditions.For an interesting summary, although not exactly the most up to date, there is a meeting report from 2000 on the possible link between MMR and autism http://pediatrics.aappublications.org/...tent/full/107/5/e84 . It has to be said that since 2000 there have been several other large scale studies which have failed to show any link between MMR and autism.TTFN,WK

Further to that I have a relevant reference 'Epilepsie bei Kindern und Teenagern ' which deals directly with the Jim Adams study.I don't have time now but I will come back later on and flesh this out into a proper post not just a hit and run link.TTFN,WK

I'd say there is a whole lot of claim and no way of judging its credibility. There are many very technical assertions and without knowing where they come from, i.e. what research they are based on, it is very hard to evaluate their worth.TTFN,WK

I seems very unlikely. I can't see what the selective pressure there would be associated with it. If the side effects had a consistent frequency of associated lethality or sterility you might see something I suppose.There is quite probably enough metabolic variation in the population that people have a range of responses to various chemical factors, but in the absence of compelling evidence that there is any significant effect associated with Thimerosal it seems pointless to look for even subtler effects which might exist at very low frequencies in a population.I certainly see no reason to suppose such differences would be recent developments.In terms of looking for genetic links to susceptibility I can't see how you could identify any candidate genes on any basis other than genes already known to be associated with Autistic spectrum disorders, which still wouldn't show any link between thimerosal exposure and the development of Autistic symptoms.Perhaps if whole genome sequencing were cheap enough it would be possible to identify novel common genetic elements associated with Autism but it would require pretty extensive investigation of a variety of populations, some of which it might be very hard to isolate. Ideally you would have a control population, a population of unexposed autistic children and a population of exposed autistic children.That is a massive effort to go for to detect a theoretical unknown genetic effect so subtle that it doesn't seem to show up statistically in any of the studies done looking at Thimerosal as a causative factor. That of course supposes that the effect is genetic.TTFN,WK

Um, I'm not just shocked by this question but also by Crash's answer.The correct answer should be virtually all of them. Smallpox vaccination has not been routinely carried out for decades. Smallpox vaccination was one of vaccinations great success stories, it was and is thought to be eradicated in the wild.Pretty much the only people in the state likely to have had smallpox vaccinations are people likely to be exposed to the virus through their work. Possibly post 9-11 there are other groups which qualify as protection against potential bio-terrorism.TTFN,WK*ABE* I see nator already addressed this briefly, but seriously this needs emphasis!Edited by Wounded King, : Typographicla errors corrected

I have to say PD, I'm pretty shocked that you've been on EvC for 3 years and aren't familiar with the concept of selective pressure.A susceptibility to some environmental factor which decreases fertility will tend to lead to less offspring. Therefore a variant without such susceptibility will tend to outcompete one with the susceptibility, all other things being equal. Therefore the proportion of insusceptible variants should increase.Unless there was some trade off between reproductive success and likelihood of development of autistic spectrum disorders, both of which could be triggered as a response to these vaccinations, then I don't see why evolution would have played any part. If there was such a demonstrable decrease it could well be the basis for selective pressure if there was a complementary less susceptible variant available. As to how specific a pressure has to be, that would vary widely depending on what the pressure was and what the different variants were. If there were differing responses with a genetic basis then they could be. Think of antibiotic resistance in bacteria. The chemicals in their environment create a selective pressure which favours bacteria with antibiotic resistance. This example also helps with the specificity question since some antibiotic resistance strategies cover a wide range of antibiotics, such as multi drug resistant transporter channels, while others could be very particular strategies for avoiding one particular antibiotic.TTFN,WK

I'm not sure I'd agree with delusion. Psychosomatic certainly but that deosn't mean that in many cases the people aren't actually better if they feel people. This will obviously work better for some things than others.For one good example of how this may operate I would recommend looking at Ben Goldacre's recent analysis of the latest studies of the efficacy of accupuncture, the ones where real and sham accupuncture worked as well as each other, and both were better than a pill placebo in the treatment of chronic back pain.TTFN,WK

Its a commonly repeated caveat in the sciences that correlation does not imply causation. It may well be that recent increases in diagnoses of Autism have occurred in the same time frame as large increases in the uptake of vaccination, so what? The vast majority of the actual research done suggests there is no causal link. you might as well ascribe the increase in divorce rates to increases in rates of vaccination, any other phenomenon which has occurred in the same time frame. So 'subtile' in fact that it is effectively undetectable scientifically. But Vaccination is so widespread that if there were a significant effect then for it not to be detectable it must be so minute that it going to make a pretty infinitesimal dent on the balance of risk.On the other hand you ascribe to a completely untested methodology of 'prevention, education and natural remedies', which has never been shown to be effective. Why do you think that this is not going to present possible significant health risks?You seem to be advocating everyone giving up vaccination wholesale and going over to an effectively untried system, why on earth would a sane society do any such thing?TTFN,WK

Sound like a word salad with a few bare assertions thrown in like croutons.If you accept that there is a necessary balance of risks concerning vaccination then why do you refuse to accept that the balance of risks favours vaccination in the vast majority of cases, is it due to anything other than your own convictions and anecdotal evidence? One problem is that the concerns aren't necessarily based on any actual effect and are exacerbated by sensational stories in the media.TTFN,WK

PD bought up this same example previously in the original version of this thread and it is predicated on some specious thinking.The most important problem is that the incidence of Mumps encephalitis associated with the urabe strain in vaccines is massively lower than the incidence associated with infection by Mumps.While the urabe strain has a higher incidence of encephalitis/meningitis than other strains it is about 1% of the chance associated with contracting mumps. There are also positive benefits to the urabe strain such that some governments still preferred to use it even when alternatives were available. For more details see my posts Message 33 and Message 61.The damage is phenomenally less than that of contracting mumps. Did you not realise that mumps encephalitis was principally associated with mumps? One obvious reason would be to encourage uptake amongst the rabidly anti-thimerosal segments of the population?TTFN,WK

Can you tell me where this supposed anomaly comes from? The only references to autism and the amish I can find in the scientific literature are in a paper discussing a genetic disorder causing language regression similar to that seen in autism (Strauss et al., 2006).TTFN,WKEdited by Wounded King, : No reason given.

I'd suggest there can be some difference. Exposure to full live viruses can provoke a stronger immunogenic response than some of the more attenuated forms in vaccines.Of course this is one of the contributing factors to people becoming much sicker when they are exposed to full live viruses and acquiring the immunity requires you to be exposed to the virus with a high likelihood of becoming syptomatic. So one has to wonder why any sane person would wish to develop 'natural' immunities to things like smallpox, mumps, polio and diptheria rather than choosing vaccination.I can understand why the balance of risks still means that vaccination in the UK for chicken pox is rare, but for many of these diseases choosing not to vaccinate just seems insane.TTFN,WK

Because they are protected by the herd immunity presented by everyone else being vaccinated.The only reported case of polio in the USA since the 70's has been an outbreak in an Amish community, seee heres. Although I believe that the most severely affected infected subject was also immunocompromised. A fuller account and details of some other polio outbreaks amongst communities with religious objections to vaccination can be found here.In this instance the form of polio was a vaccine-derived poliovirus. In other words a mutated form of one of the live polioviruses use in the oral polio vaccine. Luckily the virus doesn't seem to have mutated or recombined to the extent of regaining its capacity to produce paralysis, however were it to remain extant in immunocompromised or unvaccinated populations there is every chance that it could do so in the fullness of time.There have also been reported outbreaks of Rubella in Amish communities (Mellinger. et al., 1995).The principle reason that unvaccinated communities like the amish are not frequently exposed to debilitating viruses is that they rarely travel outside of countries where they are protected by the herd immunity of the vaccinated populace surrounding them.TTFN,WKEdited by Wounded King, : No reason given.

Evidence for this?If the mother has lost her vaccine acquired immunity over time I would agree but if she does indeed have vaccine acquired immunity then there is no reason that it shouldn't be transmitted to the child as effectively as 'natural' immunity. Ans suppose she caught smallpox? That would still be around were it not for vaccination.Since when has it been claimed that chicken pox is a killer disease? Certainly people do die of chicken pox and associated complications, estimated to be around 100 deaths a year, but it certainly isn't portrayed as a killer disease in any medical account of the disease I have come across.Can you really not discriminate between a disease like chicken pox and one like smallpox?TTFN,WK

Not in the 1979 outbreak which Rhrain referred to, that was caused by a wild strain of Polio see the CDC MMWR follow up of that outbreak. In the states it is now but there are countries in the world where polio is still endemic and people around the world travel to and from these countries. Is that a good reason to just not bother doing anything? The mutation can't readily occur if the virus is successfully eradicated. As with the polio example in the Amish population the virus managed to mutate because it could go through multiple replicative cycles in immunocompromised individuals. Without a reservoir of replicating virus the risk of such a mutation is considerably reduced, one other reason why pockets of unvaccinated people present a health risk not just to themselves. A good example might be the recent study in Brazil where they carefully followed cases of CRS and Rubella epidemiology in the region(Miranda et al., 2007).Similarly unless there is a particular cryptic form of rubella causing all of these hidden CRS cases you posit the current monitoring procedudres for rubella should be able to detect such a trend, see(Meissner et al., 2006). Except there is no reason to assume that this is what would happen. if you look at the populations where Rubella is endemic they don't have low incidences of CRS.Your argument seems to be that the well off and privileged shouldn't have to vaccinate because they can assure themselves of a sufficient standard of living not to be at risk. Even if this were true, which is by no means certain, the problem is that there are plenty of people who don't have the sufficient standard of living to ensure this and unless you live in a gated community or a bubble there is no way to ensure that you do not come into contact with them and these people are just as likely to be taken in by the anti-vax propaganda as you are.TTFN,WK