Readers may have noticed that a re-vamped "Ask a Scienceblogger" has appeared, with prior questions and responses at Cognitive Daily and Thoughts from Kansas. Aetiology gets the current installment, discussing the question, "Why is it possible to create vaccines for some microbes and not others?"
First, let me start off with a quibble about how this question was phrased, which suggests that it isn't possible to create a vaccine for some organisms. This suggests a pessimistic view not shared by researchers in the field. Just because we've not been able to create them up to this point--or more pointedly, to create successful ones with the potential for human use--doesn't mean that we're down and out. It just means that we have to come up with new targets, new technologies, and even potentially new ways of getting them tested and out into the field.
With that said, there are a number of reasons why we've not yet created successful vaccines yet, even against some pathogens that cause a great amount of morbidity and mortality (including the big three: M. tuberculosis, which cause tuberculosis, Plasmodium species, which cause malaria, and HIV):
1) Lack of knowledge about the pathogen and/or host immune response
This is the most basic reason we don't have effective vaccines against some agents--we're simply still learning about them, and don't have enough information to rationally design an effective vaccine. With HIV, for example, we're dealing with a virus that is highly variable, and can even hide out within the genome for periods of time. We know that the presence of antibody--which blocks or reduces infection with many viruses and bacteria, limiting their ability to result in development of clinical disease--alone isn't enough to put the brakes on HIV. Therefore, alternative strategies, which are less proven and not thoroughly tested, need to be employed.
For other pathogens, we may not have good candidate antigens (proteins or other molecules that induce an immune response, which often includes production of antibodies, in the host) to use as vaccines, or alternatively, the ones we do have may be highly variable and thus more difficult when it comes to vaccine formulation. Additionally, the antigens expressed by a pathogen may change from year to year (as is the case with the influenza virus), making long-term protection from vaccines elusive for the time being.
2) Testing
How do we know if a potential vaccine works? When researching a vaccine, scientists try to answer this in a number of ways. One way is to use an animal model of disease: give the animal the vaccine, and then challenge them later with the pathogen to see if the vaccine is successful in preventing disease. However, good animal models don't exist for every disease out there, and even when they do, a good reaction in an animal isn't a guarantee for the same reaction in the human population.
If the candidate vaccine makes it to human trials, these are done in four phases to first examine safety of the potential vaccine, and then to determine its effectiveness. These are quite time-consuming and expensive, which leads us to the next issue:
3) Time and money, or lack thereof
It takes an enormous amount of time and money to take a potential vaccine from the earliest stages in the laboratory into the human population at large--in the range of $600 million to a billion dollars for each new vaccine. While some vaccine research is funded by the government, much of it is carried out by private companies, who understandably want a return on their investment. Therefore, some types of diseases are prioritized over others (those which are important in developed vs. developing countries, for example). In addition to the cost of research and manufacturing, one must also add in distribution and delivery of the final vaccine, as well as the ever-present risk of lawsuits associated with receipt of the vaccine. Vaccines can be a gamble, and the payoff isn't guaranteed to be large, making some companies reluctant to invest resources in this area.
Though vaccination has been recognized as one of the ten greatest public health achievements of the 20th century, the creation of novel vaccines is more difficult today than it ever has been. Vaccines are put through more hurdles to assure safety today than they were even 20 or 30 years ago. We have lost our best preservative, thimerosal, due to unsubstantiated links to autism and other conditions--forcing a move away from multidose vials of vaccine to single-use vials, which in turn has driven up the cost of each vaccine dose (a major barrier in developing countries). The obstacles that come with creating a new vaccine are significant, but not insurmountable. New vaccines, however, likely will take more creative thinking and funding than have those of the past.
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Thanks for the comment about thimerosal. I have an autistic son and one of things that bugged about the autism activist community was how we lost five years of research going down that rabbit trail. What I wasn't aware of was that it increased the cost of vaccines for everyone. I was wondering why a well check that included a number of vaccinations pushed $1000. Now I know.
When you have a baby; will you care if 125X the recommended dose of mercury is injected into his or her 7 pound body???
Mari: none of the standard childhood vaccines currently in use in the United States contains more than a trace of thimerosal. The only kind-of exception is influenza vaccine, and it's available in thimerosal-free formulations.
If you like red herrings, go buy one at the grocery store. They don't belong on a science blog.
Rich, I'm not aware of one taxpayor penny being spent on clinical studies looking at the affects of injecting newborns and infants with organic mercury. Oh, you must mean those population studies done in other countries that banned this crap in 1992. Or do you mean the one done by the CDC which has 4 different outcomes. Don't you think that when this was published by Pediatrics (which published all the fudge studies) they should have mentioned that the lead author, Verstraeton, had already been working for Glaxo for the previous two years.
"We have lost our best preservative"? Who do you think you are kidding? Lets deal with facts, and this is not one of them. In 1982 the FDA banned Thimerosal from over the counter medications because of injury and death from mercury poisoning and because it did not work. There are at least 7 peer reviewed papers since 1948 that tested the effectiveness of Thimerosal as a preservative and all found it to be a weak agent as an anti-infectious agent. One study found it no better than water. In 2004 Chiron flu vaccine supply was contaminated with Serratia bacteria IN SPITE of containing mercury. This cost the company millions and the US over half of its flu vaccine supply. Almost nowhere in hospitals and clinics can you find multi-use vials of anything. It is more important in developing countries that have less reliable sources to expect them to keep a multi-dose vial sterile. Removing the added cost of a preservative is more than enough to make up for the marginal cost of a single vial. Furthermore, a single use syringe is the best way to avoid needle re-use that according to the WHO was responsible for thousands of cases of AIDS in infants in Africa.
The flu vaccine schedule has been expanded and heavily promoted since 2004, about the time Thimerosal was out of DTaP, HiB and HepB vaccines. As a result the total mercury a child will get by age 5y is 53% of the peak in 1999, so Thimerosal is still a major issue today.
This column has missed the mark badly on facts, therefore your opinion is unsupported.
To lament the reduction in the use of thimerosal in infant vaccines is akin to reflecting back on the loss of tetra ethyl lead as an additive to gasoline to avoid that terrible "knock" if you remember. Luckily the knock seems to have disappeared on its own but we also lost that "boosted octane" level. Please stop making unsubstantiated generalizations about things you appear to know little about and misinforming the public, by downplaying flu shot exposure to pregnant women and seniors. Wake up and look for safe products to try to sell if you are really interested in human health. You do not need to have a disabled family member and a suspicion about what might have effected them to act to protect people from dangerous substances, but having an unfortunate circumstance may make someone more aware of the damage that is being done every day. Perhaps you should listen to people and look at individuals rather than worship statistics that someone ordered prepared. How many seniors with health issues have regular exposure to thimerosal? This one isn't even in your list of other unsubstantiated conditions, because no one has ever looked. When people in Iraq were exposed to mercury based fungicides the claim was that they didn't recognize the skull and crossed bones symbol what is your excuse?
Ignoring the mercury nuts for the moment... I guess I always assumed that the reason there was no vaccine for HIV was that the first thing it does when it enters the body is disable the immune system, thus immune response is impossible. Is that not true? Would it be possible for a properly prepared immune system to destroy the virus before the virus destroys the immune system?
A study commissioned by the Kaiser Family Foundation and conducted by researchers at the Harvard School of Public Health (M.B. Rosenthal and A.M. Epstein), Massachusetts
Institute of Technology (E.R. Berndt), and Harvard Medical School (J.M. Donohue and R.G. Frank) back in 2003 showed that this industry had no problem investing several billion dollars each year schmoozing the doctors who administer their poisons.
Yet they're "reluctant to invest resources in this area"? And you don't think they should actually be held accountable for the safety of the very products they sell?
If you've followed the politics of autism over the last few years, you'd see just how (tragically) laughable these notions are.
Please stop defending an industry that sugar-coats the ROI argument and uses it as an excuse to harm innocent children.
-randy
"Additionally, the antigens expressed by a pathogen may change from year to year (as is the case with the influenza virus), making long-term protection from vaccines elusive for the time being."
Indeed. And even more startling are those infections that can change from day to day. Trypanosomes, which cause sleeping sickness, periodically change their coat molecules to one of a thousand potential candidates. Trypanosomes have genes for a vast wardrobe of coat proteins that they cycle through systematically. Designing a vaccine against any one would be futile.
It is also worth remembering that the "immune system" is not as simple as some vaccination "rethinkers" make out. Different parts of the immune system play a decisive role in different diseases.
I know there are groups looking at vaccines designed to stimulate cell-mediated immunity (rather than antibodies) to the malaria parasite.
Development and regulation of cell-mediated immune responses to the blood stages of malaria: implications for vaccine research.
Constant exposure to the malaria parasite at very low levels can induce cell-mediated immunity without the development of antibodies.
I was looking for an article discussing cell-mediated immunity and possible HIV vaccines and found this excellent primer by Richard Jefferys.
Vaccines that trigger cellular immunity: what can we hope for?
In 1982, the FDA proposed a ban on over-the-counter products that contained thimerosal (like mercurochrome and merthiolate) because of the chemicals' demonstrated toxicity to animal fetuses and humans. (The ban did not go into effect until October 19, 1998.) In 1977, five years earlier, topical thimerosal killed 10 babies at a Toronto hospital when it was dabbed on their umbilical cords as a disinfectant. In 1991, thimerosal was banned for use in injections for animals.
I see I've struck a nerve. I've discussed thimerosal previously on this blog for those who want to see my views, but again for the record:
1) I have children; they are fully vaccinated. And I was vaccinated for influenza while pregnant.
2) I've read the research on thimerosal. I've not seen anything to make me believe any connection exists between thimerosal and autism or any serious adverse condition.
Give me more than anecdotes, fear-mongering and conspiracy theories. Thimerosal is a non-issue.
David, while I certainly agree that needle re-use is a bad thing, I don't see how the two necessarily correlate. One can still re-use needles even with single-use vials, and one can use new needles with a multi-use vial.
Can one of you point me to more info on the FDA thimerosal OTC ban that aren't from "thimerosal causes autism" sites?
I also find it delightfully ironic that so many of the anti-thimerosal folks use the Geier's research, and at the same time decry the profit and ethics of pharmaceutical companies.
Dear Tara,
I would be grateful until the day I die if you could point me to the safety research conducted by the FDA on the injection of ethylmercury into infants. So far I can find nothing, but I am assuming that you must have access to a peer reviewed study which gives a scientific foundation to your assertion that thimerosal is safe. Please don't dismiss 1.5 million American families as anecdotal or inclined to promote fear mongering. We need safety studies. All best, Caroline
Why are you limiting it to the FDA? Thimerosal was introduced in the 1930s; I'm not sure I could find similar data on from the FDA, say, aspirin either, or penicillin, or other old drugs. Instead, we have years of studies conducted by researchers and other agencies around the world that show their safety (or lack thereof, for example aspirin in children with fevers).
And Caroline, you don't speak for all American families with an autistic child. Many have come to the conclusion that their child's condition has nothing to do with thimerosal or vaccination, a conclusion supported by the evidence.
For Mari:
Thimerosal dissociates into equal masses of salicylic acid and ethylmercury. However, there is currently limited human data for exposure to either thimerosal or ethylmercury. Therefore exposure limits are based on the more extensive toxicity data for ethylmercury's close relative methylmercury. The US EPA limits infants' cumulative exposure to methylmercury to 69.3 µg over the first 6 months of life; this figure is based on a female infant on the 5th percentile for weight (i.e. as small and therefore as vulnerable to toxicity from a xenobiotic as any healthy infant is likely to be).
Now: 125 times that exposure limit would be 8.68 mg of methylmercury. (NB. there is no recommended dose as it has no physiological rôle.) That is the same mercury content as 9.23 mg of ethylmercury, or 18.6 mg of thimerosal. I know of no country whose vaccination schedule that exposures infants to anything like that amount - do you?
PS. Do you like tuna?
"I've read the research on thimerosal. I've not seen anything to make me believe any connection exists between thimerosal and autism or any serious adverse condition". Tara, go to Pubmed and type in thimerosal and autism. You will get references to 77 papers. Type in thimerosal alone and you will get 1200 hits. To say there is no evidence is ridiculas. All you're doing is repeating the CDC, AAP and AMA's propoganda.
"It takes an enormous amount of time and money to take a potential vaccine from the earliest stages in the laboratory into the human population at large--in the range of $600 million to a billion dollars for each new vaccine."
Tara, those numbers are from Tufts' center for pharma studies for small molecules, and they're problematic themselves and also problematic for application for biologics like vaccines.
Less biologics wash out 'cos of side effects than is the case for small molecules, and the clinical development time tends to be shorter (Not familiar with vaccine development time, but recombinant proteins a la Genentech or Amgen take about 2 years less to develop than .
Also, Tuft's numbers are on the (IMHO) high end for the accounting costs used in their estimates, and they also are economic (i.e. opportunity) costs expressed as future values, not expressed as accounting or out-of-pocket costs: i.e. they're calculated including a rate of return on the investments of 15% (IIRC), so a hefty profit is assumed and factored into Tuft's numbers. They also include basic R&D overhead costs and the cost of failed drug candidates. And yes, they assume the same rate of return on the overhead and the investment in failed drugs.
To draw an analogy, to show how problematic Tuft's numbers are: you buy a house for (say) $400k, and live in for ten years. But let's assume you could have invested the money for those same ten years at 15%. So at dinner parties, using Tuft's methodology, you'd say the house "cost" you $1,600K. Both are the same Net Present Value at 15%, but one is more eye-popping than the other.
The old Office of Technology Analysis had a good report on this back in oh, 1991. Unfortunately, as Gingrich shot the OTA in the head in 1995, we don't have recent unbiased quality analysis of Pharma R&D costs.
Johnny, you're right: I just typed autism and thimerosal into Pubmed, and I did indeed get 77 hits. When I told it to limit itself to papers about humans with abstracts, that dropped to 44.
But it's really too bad that you seem to be illiterate, because you obviously decided that the magic 77 number was all you needed to know. It's not. You actually have to go in and read the material. If you'd done that, you'd have found out that most of the results (in the 44 papers with abstracts) don't show any association between thimerosal and autism, and most of the ones that do are from the mercury mafia types like Body Haley or the odious Geiers.
Don't try to impress people by just throwing around numbers, especially when you don't know what the numbers mean.
Ironically (or, at least, interestingly), the reason anti-vaccination advocates have so much material to work with is that the possibility of mercury toxicity in vaccines was taken very seriously and investigated very thoroughly. In 2002, Arthur Allen wrote an excellent profile of Neal Halsey, the pediatrician whose concerns were a major factor in starting those investigations. His article has been widely reprinted, and seems to be regarded by many in the anti-mercury camp as a vindication of their position. Unfortunately for that position, by the time the dust settled, thimerosal was found to be ... well, safe. Not that it's made a lot of difference. Some minds, under the toxic influence of conspiratorium and self-righteose -- both present in high concentrations on the Internets -- are too badly injured at this point to be changed.
Peter: my question should have been in past tense since thimerisol has been largely removed from vaccines since it is a known neurotoxin; FYI On July 9,1999 "Thimerisol in Vaccines: A Joint Statement of the American Academy of Pediatrics and the Public Services" was released "Some children could be exposed to a cumulative level of mercury over the first 6 months of life that exceeds one of the federal guidelines on methyl mercury" the calcution of how much mercury was being injected into American infants was given to the FDA's Center for Biologics Evaluation and Research. Despite the differences between ethylmercury and methylmercury, FDA researchers assumed the 2 equal in toxcity. When FDA converted the amount of ethylmercury in vaccines from from volume percentages to actual weight, they found that most American children were being exposed to level in exess of federal limits, especially when calculated in single-day bolus doses. A child weighing 5 kilograms could have been exposed to 62.5 micrograms of mercury in a single day; 125 times more than the EPA limt (.5 micrograms a day)
PS I never eat tuna- heard it's full of mercury
"I have children; they are fully vaccinated. And I was vaccinated for influenza while pregnant."
I wish your kids the best of health (sincerely) - as I do with any child (vax'd or un-vax'd). I believe 100% in informed choice - something apparently lacking in public health. Where do we draw the line when it comes to vaccines or any intervention for that matter? the benefit to society vs the risk to the individual? this is an unbalanced risk equation, but that's what's I've seen being used to push a parent into compliance.
"I've read the research on thimerosal. I've not seen anything to make me believe any connection exists between thimerosal and autism or any serious adverse condition."
was your focus on epidemiology or toxicology (or both)? are you saying that research to support a mercury hypothesis simply does not exist, or that any such studies (in your opinion) are essentially "junk"?
"Give me more than anecdotes, fear-mongering and conspiracy theories."
the persistent yammering on the evening news about the impending bird flu epidemic? the pharma rep's huge posters with big pictures of really sad kids, hanging in the ped's office? the media trashing of parents with legitimate concerns about vaccine safety (Nancy Snyderman taking a huge dump on BL Fisher a great example)? all these things seem to do a nice job of frightenting the hell out of people.
"I also find it delightfully ironic that so many of the anti-thimerosal folks use the Geier's research, and at the same time decry the profit and ethics of pharmaceutical companies."
nothing about this controversy is delightful - not even the irony you suggest - not matter how you feel about the Geiers, that's bad choice of words Tara. I might want to place my trust in David and Mark Geier, vs, say, Merck and the FDA - given that the latter has a proven track record for tampering with research, and then trying to "silence the dissenters". Are you saying that the Geiers are in this same league?
Dr David Graham JAMA editorial:
http://jama.ama-assn.org/cgi/content/full/296.13.jed60058v1
His Joe A. Callaway award acceptance speech:
http://www.corporatecrimereporter.com/graham122804.htm
"I can guarantee you, there are other whistleblowers at FDA," Graham said. "There are many whistleblowers at FDA. Fear has them by the throat. And they struggle with their conscience and they struggle with the wrong that they see, and they are paralyzed by their fear. And they are looking to see - can that Graham fellow get away with committing the truth?"
ironically (hardly delightful), the other recipient of this award was Mark Livingston, a pharmaceutical quality control specialist who filed a lawsuit in federal court alleging that Wyeth Pharmaceuticals compromised the manufacturing process for the Prevnar vaccine in order to meet demand.
public health efforts seem to be conflicted - would you agree, or would that make you a conspiracy theorist as well? granted some pharma-related businesses save lives - and any business has to make a profit to survive - but some have done harm in the name of maximizing profit - there's good and bad everywhere, but until all conflicts are gone, then all trust is also pretty much gone.
-randy
It is heartening to see all of the mercury wingnuts, with their undisclosed vested interest in suing the drug companies, come out of the woodwork whenever their pet theory is challenged. I guess now that their chances of winning their big omnibus lawsuit are just about zero they're going to take their frustrations out on random science bloggers. They're clearly not interested in science if they think the blatantly lying Geiers are credible sources.
Yet another new paper that fails miserably to correlate autism and thimerosal, this time concerning the use of Rhesus Ig in pregnant women:
http://www.eurekalert.org/pub_releases/2007-05/uom-sfn051007.php
anonimouse
no lawsuits here - never have been
not part of the omnibus proceedings
been 'out of the woodwork" for several years
very much interested in the science - hence my request for Tara to provide a bit more clarity.
I am also interested in the financial and political drivers, as they appear to be at least as important in this ongoing issue.
my son is mercury and lead toxic and he is very sick - it's not enough for anyone with any conflicting interest to tell me, directly or indirectly, that I'm just too damned scientifically illiterate to understand the concept of correlation vs causation.
I just happen to believe that the deliberate and unnecesary injection of a any toxin into a baby is idiotic, and that one-size-fits-all medical policy of any kind is reckless.
if you could convince me today that mercury is in fact a non-issue, my contempt for this broken system still remains intact.
i'm just an average guy with a big bag of various clues about all the factors (mercury included) that may have contributed to his decline
guess that just makes me a "generic" wingnut
sorry if that bothers you
-randy
randy: "I just happen to believe that the deliberate and unnecesary injection of a any toxin into a baby is idiotic, and that one-size-fits-all medical policy of any kind is reckless."
Chlorine is toxic. Wait, that stuff is in saline!
As for the "one size fits all" issue. Yeah, that's a problem. Try to work out a means of predicting specific cases where a treatment will fail. It's not at all easy.
"if you could convince me today that mercury is in fact a non-issue, my contempt for this broken system still remains intact."
Good for you. Whatever. Have you considered moving to Fiji instead?
I just had the misfortune to watch a couple of videos on Youtube about the nutzy PETA. They claim to be in favor of supporting the "liberation" of all animals. However, they don't seem to mention bacteria, protozoa, amoebas.
Are they technically animals--I don't mean the PETAs? Decades ago in high school I was taught that they were. Maybe there is a newer scientific classification nowadays. If they are, what is PETA doing to protect bacterial rights? For that matter, why isn't PETA interested in promoting plant liberation?
"I just happen to believe... "
I would say that that is the problem. Your belief doesn't matter (though most of Western society is brought up with the idea that belief is important). It's just simply not relevant, nor is it a good tool to bring to the problem.
All of the evidence suggests that thimerosal does not cause autism. I was inspired last night to go back and reread some of the Geier papers. They are astoundingly bad. The simple fact is that based on their data, you can make no conclusion about mercury one way or the other. And every credible paper in the field you can make solid conclusions. The conclusion is that thimerosal is not involved in autism.
Now, you can say that I'm biased. After all, I'm an academic scientist. But to say that I'm wrong, you also have to say that every member of the National Academy panels on autism is wrong. You have to say that the CDC is wrong and the FDA is wrong. You have to say that every employee of the relevant pharmaceutical companies are wrong. And every independent investigator in multiple different countries is wrong. All these groups are either profoundly stupid (which would be an amazing thing in itself, that an entire field could be populated by morons) or they're involved in such a massive conspiracy that would put even the Kennedy assassination conspiracy theorists to shame. We're talking about thousands of people here.
So if you don't "believe" the data, and you don't "believe" the relevant professionals, do you only "believe" if God comes down and tells you herself?
"Chlorine is toxic. Wait, that stuff is in saline!"
high school chemistry was long ago, but isn't chlorine derived (typically an industrial process) using sodium chloride as the raw mat'l? are you saying that we're injecting chlorine into people when we use a saline solution?
"As for the "one size fits all" issue. Yeah, that's a problem. Try to work out a means of predicting specific cases where a treatment will fail. It's not at all easy."
not easy - but it could be as simple as the doctor asking if the family has a history of autoimmune issues, before injecting a substance which might otherwise be contraindicated (e.g. MMR). I think a lot (most?) doctors do so - but some don't.
Have you considered moving to Fiji instead?
not really - so far I still have the right to express my "beliefs" here
"Your belief doesn't matter... it's just simply not relevant, nor is it a good tool to bring to the problem."
It isn't a good tool to bring to the problem - neither are any of the other "bad tools" (political pressures, conflicting interests, etc.) that get shoved into the problem. Are you suggesting these things don't exist, or that they're not relevant?
"All of the evidence suggests that thimerosal does not cause autism."
Some of the evidence suggests that thimerosal is involved in things like the disruption of certain metabolic pathways, etc. If even one child suffers an adverse reaction - mercury poisoning - and we label him/her "autistic" as a result - then the statement "thimerosal does not cause autism" becomes "thimerosal rarely causes autism" - except from the population point of view, this kid is not statistically significant, so he doesn't "count".
Sorry - not trying to turn this into a "benefit of the herd" argument. I don't know if that discussion even belongs here. But I'd say that's where my belief does matter, as this becomes less of a scientific debate, and more of a philosophical one - "we could have spared that kid, if it wasn't just too damned expensive, or too difficult..."
"Now, you can say that I'm biased. After all, I'm an academic scientist."
Actually I wouldn't say that makes you biased, assuming you have no "skin in the game". Would you say that I'm biased 'cause I'm a parent with a disabled child? I trust the above statement was not a subtle dig at the fact that I'm not in the same league, academically.
"We're talking about thousands of people here."
That statement also describes a whole lot of parents who lost their kids to things like autism. Some sharp pencils in that box too. I'm thinking most are not conspiracy theorists (personally I hardly expect that a bunch of scientists line up at the various agencies every day to figure out new and more diabolical ways to harm children). If you disected the ranks of FDA, CDC, etc. you'd probably find a lot of decent hard working people there. You'd also find some problems, just like you would in any other large, politically charge organization.
"So if you don't "believe" the data, and you don't "believe" the relevant professionals, do you only "believe" if God comes down and tells you herself?"
The "relevent" professionals? I'm surprised you didn't use the work "prestigious" anywhere. Dr Ayoub, I guess that makes you, well, you know, not relevent.
If God showed up I'd guess her focus would be on that statistically insignificant kid, as opposed to talking about the thousands we apparently did not harm.
-randy
"Your belief doesn't matter... it's just simply not relevant, nor is it a good tool to bring to the problem."
It isn't a good tool to bring to the problem - neither are any of the other "bad tools" (political pressures, conflicting interests, etc.) that get shoved into the problem. Are you suggesting these things don't exist, or that they're not relevant?
"All of the evidence suggests that thimerosal does not cause autism."
Some of the evidence suggests that thimerosal is involved in things like the disruption of certain metabolic pathways, etc. If even one child suffers an adverse reaction - mercury poisoning - and we label him/her "autistic" as a result - then the statement "thimerosal does not cause autism" becomes "thimerosal rarely causes autism" - except from the population point of view, this kid is not statistically significant, so he doesn't "count".
Sorry - not trying to turn this into a "benefit of the herd" argument. I don't know if that discussion even belongs here. But I'd say that's where my belief does matter, as this becomes less of a scientific debate, and more of a philosophical one - "we could have spared that kid, if it wasn't just too damned expensive, or too difficult..."
"Now, you can say that I'm biased. After all, I'm an academic scientist."
Actually I wouldn't say that makes you biased, assuming you have no "skin in the game". Would you say that I'm biased 'cause I'm a parent with a disabled child? I trust the above statement was not a subtle dig at the fact that I'm not in the same league, academically.
"We're talking about thousands of people here."
That statement also describes a whole lot of parents who lost their kids to things like autism. Some sharp pencils in that box too. I'm thinking most are not conspiracy theorists (personally I hardly expect that a bunch of scientists line up at the various agencies every day to figure out new and more diabolical ways to harm children). If you disected the ranks of FDA, CDC, etc. you'd probably find a lot of decent hard working people there. You'd also find some problems, just like you would in any other large, politically charge organization.
"So if you don't "believe" the data, and you don't "believe" the relevant professionals, do you only "believe" if God comes down and tells you herself?"
The "relevent" professionals? I'm surprised you didn't use the work "prestigious" anywhere. Dr Ayoub, I guess that makes you, well, you know, not relevent.
If God showed up I'd guess her focus would be on that statistically insignificant kid, as opposed to talking about the thousands we apparently did not harm.
-randy
That statement also describes a whole lot of parents who lost their kids to things like autism.
Being a parent of a child with a disease makes one an expert of the symptoms of that disease. It hardly makes one an expert on the cause. Would the parents of Down's Syndrome children have been experts on the cause of Down's prior to the discovery of trisomy 21? People used to think it was caused by injuries during birth. Would parents' opinions have mattered then? Would you go to a parent for advice about solar flares? Would you go to a parent for information about tumor progression?
Yes, my statement about relevant professionals does make gentlemen like Ayoub and the Geiers irrelevant. If you can't interpret data better than a second year graduate student, you're not a relevant professional. If the material that they wrote about was less important they would be laughable. Given the gravity of the situation, I would say their incompetence borders on criminal.
But again, let's chalk this up. You have several MDs who think mercury causes autism. You have thousands of parents who think mercury causes autism (including several sharp pencils). On the other hand, you have the vast majority of the scientific establishment who thinks that every piece of data produced by the Geiers is tripe. You give the papers the Geiers have produced to a scientist like me, who is not in the field, and I can immediately catch several major problems with each paper.
"Alas, to wear the mantle of Galileo it is not enough that you be persecuted by an unkind establishment, you must also be right."- Robert Park
And sadly, for the Geiers and all the folks who they have duped, they couldn't be more wrong.
"I trust the above statement was not a subtle dig at the fact that I'm not in the same league, academically."
It's not a dig at all. I'm sure you know all kinds of things about your profession that I do not. But keep in mind, your average Ph.D. scientist spends 10-12 years training to be a scientist. And years more mastering their work. I wouldn't go to a scientist for plumbing information. I wouldn't go to an MBA for dentistry information. Similarly, I wouldn't go to a parent for scientific information. Saying that there are many clever parents of autistic children simply isn't relevant. They could be brilliant, but if they aren't trained and focused, they likely will do a lousy job of interpreting data (as has been well-demonstrated by the mercury groups of the last ten years).
"You have several MDs who think mercury causes autism. You have thousands of parents who think mercury causes autism (including several sharp pencils). On the other hand, you have the vast majority of the scientific establishment who thinks that every piece of data produced by the Geiers is tripe."
Does the opinion of the entire scientific community and this entire thread hinge on the Geiers? Are you saying every piece of toxicology or similar evidence ever produced to implicate mercury is junk? Sorta the same question I asked earlier.
Randy,
I ignored that part of your problem because I thought others had dealt with it well. The toxicity of "mercury" isn't relevant, any more than the toxicity of "chlorine" is relevant to our consumption of table salt (table salt is half chlorine, you know).
The only question is the toxicity of the particular mercury form you've been exposed to (in this case thimerosal, which breaks down into ethylmercury). And the doses that people are exposed to are safe*.
*Note I say the doses that people are exposed to. Saying that anything is safe is always a relative statement. Everything is toxic in the wrong doses. Water. Oxygen. You can read more about that here: http://conspiracyfactory.blogspot.com/2007/05/everything-is-toxic.html
It's not just the dose that renders the saftey aspect relative. Not trying to insult your intelligence - nothing you don't already know - just noting that there are other considerations like regimen, route, excretion pathways, etc. that are equally important.
Aside from that, the FDA regulations define safety as "the relative freedom from harmful effect to persons affected, directly or indirectly, by a product when prudently administered, taking into consideration the character of the product in relation to the condition of the recipient at the time".
So - knowing something about the LD50 and lethal dose, but knowing nothing about my son's condition at the time (or over time), what can anyone tell me about a "safe" dose of anything for him then / now / later...?
Safe for the population, in general, relatively speaking, but only relatively safe for the individual if that person's "condition at the time" is factored in. Medicine needs to focus on the individual vs the herd. Some physicians are tuning in to this.
No doubt you will tell me that if there are enough of these kids, a properly designed epidemiological study should pick this up. I'll let those more versed in the topic argue the merits of the studies to date. At the same time, the toxicological studies that the FDA discounts either as flawed (you probably do as well) or not specifically showing causation to autism (do all the authors themselves even make this claim?), still raise some serious concerns about what we don't know today.
FDA response to CoMED petition: "these studies do not prove that thimerosal contributes to the risk of autism for the following reasons: The biochemical and molecular pathways and processes relevant to the expressions of autism are currently not known."
"the dose levels of thimerosal and its metabolites studied in these in vitro systems may not model the actual cellular levels of exposure in the context of the human body."
These studies do not prove causation, but they do identify possible biochemical pathways (very good clues), and they may actually model cellular levels in the human body - these data are not ruled out. We just don't know today. More study needed...?
For me - more sleep needed - thanks for taking the time to reply.
-randy
No doubt you will tell me that if there are enough of these kids, a properly designed epidemiological study should pick this up.
Bingo. Not one. Not two. But several epidemiological studies have failed to find this link (and well-designed experiments, too). Game over. And now an "experiment" in the U.S. is ongoing where for several years there has been essentially no thimerosal in childhood vaccines, and yet autism rates are still going up. What does that tell us? It tells us that thimerosal does not cause autism. Nothing more, nothing less.
It matters not one whit that there are levels of thimerosal that will become toxic. As i posted above, there are levels of everything that are toxic. The question at hand is "Does thimerosal cause or contribute to the causation of autism?". The answer to that question is a definitive "no". The other issues you bring up are not related to that important question. It doesn't matter that you can think of a possible mechanism for a phenomenon that doesn't exist.
Are there levels of thimerosal that are toxic? Absolutely. I cannnot stress enough: there are levels of everything that are toxic. If you read the link I gave you, you saw there's a woman who killed herself drinking too much water in a water drinking competition (trying to win a game system for her kid). Messed up her electrolytes and died. *Everything* is toxic. But after saying, "Water is toxic." can I then say "that means water could cause autism?". No. There is no evidence that water causes autism (that said, I doubt anyone has looked as hard as people have looked for a link for thimerosal). So water is a more likely culprit in autism than thimerosal. Should I start thinking of mechanisms whereby water could cause autism? No. That would be a serious waste of time until I demonstrate a causal link between autism and water.
Dear Dr. Aunt Tara,
Despite the fact that I'm still standing by the mailbox each and every day waiting for an envelope from Iowa, I'm going to share a little good news with you.
NC Legislature ratified a bill today (I'm assuming that it now goes to the Governor for his signature, although I thought that's what "ratified" meant) to require all schools in NC to provide information on HPV, information on the HPV vaccine, and information on cervical cancer, to all students between grades 5 and 12 at the beginning of each school year.
My only three regrets:
1. The bill doesn't require students to actually get the vaccine.
2. There seem to be some weasel words in there to allow "religious schools" to not distribute the material (the Division of Nonpublic Education is required to provide it to the school).
3. Nine bone heads in the General Assembly voted against this bill. (None in the Senate.)
Anyways, just wanted to share.