Dear friends, Firstly I would like to thank the community for the overwhelming engagement with the topic of vaccination and to my letter, and other excellent submissions I have seen on Lakewood Scoop. I think we can all only gain from open transparent discourse. I would also like to thank the editors at the Lakewood Scoop for facilitating this important community discussion.
Declaration of bias – In my responses to the last letter in Lakewood Scoop I outlined my funding sources and my email is available with a cursory search. I have nothing to hide. I am receiving no financial gain for writing these articles, nor does it improve my business, since I am paid a university salary and do not see patients directly in the United States. The patient care I do provide in Malawi when I am there is provided pro bono, and the Lakewood Scoop is not very widely read in Malawi anyway. I also don’t much like the public exposure, but must involve myself in this issue under the positive mitzva of rappo yerappe and the negative one of lo saamod al dam re’echa. You all know exactly who I am and how I get paid. Some persons responded by claiming I am corrupt in some way. I would ask that persons making such statements also provide – as I have done – their full names, contact details, funding sources and affiliations, so readers can judge. Some persons have emailed me personally saying that I am uneducated about vaccines. With this I agree. Though I am very well trained in vaccine science, but as in every area, what remains to be learned is infinitely greater than what has already been achieved, as a drop in the ocean the great Rabbi Eliezer put it. Yes I am a doctor (both medical and research) but I do not ask you to trust me on that basis, I have invited you to question me. So please let us all talk to one another bedarchei noám. We are real people, not anonymous screens and keyboards.
I would like to address a few questions that have come up, that I did not have time to address sufficiently in the online responses.
Topic 1: “Other” ingredients in vaccines
A number of persons have raised questions regarding the safety of ingredients other than the immunogen (the ingredient that generates the desired immune response) contained in vaccines.
This is a big area, so I will just address some headings really, veídach zil gmor (the rest [I encourage you to] go and learn)!
There are three broad groups of “other” ingredients in vaccines, namely preservatives, stabilizers and adjuvants. Additionally there may be miniscule amounts of residuals from the manufacturing process.
The use and safety of such ingredients is regulated by the United States Code of Federal Regulations. And the associated testing and licensing form part of each vaccine product’s Biological License Application to the FDA.
I will explain each category.
For vaccines to be administered safely they must be protected from being contaminated by bacteria or fungi. Without this, vaccines would be dangerous, and tragedies have occurred in the past because of contaminated material. There are a range of chemical compunds used for this, and the law requires that they be used in non-toxic amounts. I should add that every substance can be toxic at doses that are too high. Even oxygen or water – the basis of life – when administered at too high doses can be deadly. So the dose matters. One widely known preservative that was once used in some vaccines (not all) but is no longer used in pediatric vaccines in the US is thimerosal (or thiomersol) which is a derivative of mercury. Even though studies have shown that the amount used is safe and although the World Health Organization and the Global Advisory Committee on Vaccine Safety found no evidence of concern, there was community concern about its use, and it was removed from routinely recommended pediatric vaccines in the US in order to sustain community confidence in the vaccine program (so you should know your voices are heard!).
(Given the strong feeling about thiomerosal I expect some respondents of Lakewood Scoop will respond strongly to this point. I state in advance that I will not have time to address issues raised by such responses, please understand I am not avoiding you, there is available evidence out there and I cannot revisit everything to everyone’s satisfaction.)
For vaccines to remain active and given the tiny amounts of immunogen in vaccines, in order for this active ingredient to be effectively delivered to the recipient, there needs to be material in which the immunogen is delivered. This material also needs to protect the immunogen from being destroyed by temperature changes etc. Examples of stabilizers are sugars, salts, buffers (to maintain the correct acidity), amino acids and proteins (like gelatin or albumin). The last of these, proteins, can carry a very very remote risk of an allergic reaction. There is also a theoretical risk of transmission of other infections, but in the trillions of doses that have been given over years, this has not occurred.
These are chemicals whose purpose is to increase the effectiveness of the vaccines, by enhancing the immune response. One such example is alum (a form of aluminum), which has been used in vaccines for almost 100 years. Concerns are heard in the community about the safety of this chemical. Apart from the many years of accumulated experience with its use, specific studies that have examined this issue in depth have shown alum to be safe. As scientific techniques improve studies are continuing all the time, and this issue continues to be actively studied in 2018. Scientists keep postulating and testing ways of examining whether alum is not safe, and so far it remains safe. Lay readers should note that it is a strength of science that it tries to disprove its own hypotheses. Accumulated evidence and many studies show alum is safe, but if new evidence emerges that it might not be safe, it is important that such new evidence is published and addressed. An attitude of just assuming that things are fine and not pursuing possible concerns is irresponsible, arrogant and will rightfully undermine community trust. But at the same time it would be wrong to conclude that “the jury is out” on the safety of alum, or some such conclusion. The overwhelming weight of much evidence is consistently reassuring. And the most reassuring thing is that the scientific community keeps looking at this issue critically.
This is a substance that remains in the vaccine as a result of the manufacturing process. One example that sounds scary is the chemical formaldehyde, which is a known toxin at high doses and is a carcinogen. Formaldehyde however is also a naturally occurring substance in the body and exists in the blood at low levels as part of normal physiological functioning. The key issue here is, again, dose. The total accumulated amount of formaldehyde that a child is exposed to from all vaccinations received is miniscule compared to the natural amount of formaldehyde that is produced and cleared by the body each day. A 2013 study by the FDA concluded that they “do not find it plausible that vaccine-related formaldehyde…[is]…unsafe.”
There are many other substances that are a part of the vaccine manufacturing process. Clearly I cannot discuss each and every one, nor can I respond to every respondent to Lakewood Scoop that asks “what about this?” and “what about that?” though I respect the questions. We cannot cover the whole field here, I hope most people would understand and accept that. I will also say that I am certainly not an expert in vaccine manufacturing, though I hope most of you would accept that I am not trying to sidestep any sensitive topics. The main message I want to convey is that all these “other” substances in vaccines are known about, monitored, regulated and evaluated. The scientific literature is active on this issue, and safety concerns are raised and pursued. This is good, because the only way to remain safe is to avoid complacency. The same holds on our streets and the same holds in science.
Topic 2: Herd protection
Herd protection (differs slightly from herd immunity, but for a non-technical audience not much nafka mina) occurs for many infectious diseases, but not all. It depends on the mode of transmission, whether there is a carriage state for the organism and other factors determining transmission dynamics, it is not the same everywhere. Intuitively, for most infectious diseases if there is less of the disease around (lower prevalence) as a result of it not being the right season or because of widespread vaccination, then there will be fewer new cases arising (lower incidence). If vaccination also reduces or halts onward transmission that can also protect the unvaccinated. For example, with the bacterium Streptococcus pneumoniae (a major cause of bloodstream infection, meningitis and pneumonia) the introduction of the childhood vaccine in the US and the UK was associated with substantial reductions in disease also in older age groups. It is thought that about 65% of under-5 year olds need to be vaccinated for this herd protection to occur, though research is ongoing. Measles however is a among the most infectious of all transmissible diseases, and thus achieving herd protection requires very high rates of community vaccine coverage, around 94-95%. This is difficult to achieve, especially where there is reticence to vaccinate among some subgroups in the community. For some conditions, like pertussis (whooping cough) almost all the life threatening cases will occur in young infants who are too young to be vaccinated, so herd protection is particularly important. It is especially important that young adults are protected since they are the ones having young children. Protection conferred by the pertussis vaccine wanes by about 10-15 years following vaccination (even pertussis disease does not generate great immunity), making young adults (even those vaccinated as infants) vulnerable again, as then are their subsequent newborns. For this reason in many places the pertussis vaccine is now given in pregnancy. Other methods that have been tried around the world include giving a booster in adolescence or “cocooning” that is vaccinating the family of the newborn. Bottom line – herd protection is an important phenomenon but is not equal across all infections or places. Now the notion of herd protection is often used in moral arguments about our obligation to be vaccinated in order to protect others. I want to separate fact and value here. We should continue to evaluate the drivers of herd protection in order to maximise the overall community impact of vaccines. Studying herd protection mechanisms is important. We should use the best available evidence about herd protection. However, what we as a society do with such facts, in terms of motivating behaviour change say, is a matter of values and moral argument. So is something that should be discussed and debated. Moral deliberation should be informed by best available science and should themselves guide the science, but are separate to science.
Topic 3: Reporting bias and vaccine safety surveillance
We learn by reading and hearing about things in the world. It is sometimes difficult to separate out our evaluation of the quality or importance of some piece of information from the volume of that information. A simplistic example – if my 3 year old is screaming and whinging there may be something seriously wrong, or maybe her brother just took her toy. But if my 3 year old is rachmana litzlan listless and not feeding well, there is less noise but much more cause for concern. This silly example is just to separate out the importance of something from how loudly we hear about it. The same holds in what we hear about vaccines in general. When an adverse event occurs (that may be real and very serious, nothing silly when this occurs) it is often spoken about widely, yet when the millions of doses are given without any problem nobody informs us of this. You hear bad news, you don’t hear when nothing happens. By the very same logic, since most infections resolve with no severe effects we might hear someone say that “40 years ago I had measles and I turned out fine”. We are more likely to hear from such survivors than from those who lo aleinu died of measles, for 2 reasons: A) there are far more people who survive measles than do not, B) Survivors are alive to tell of their illness years ago, while those who died cannot speak. So information about disease being mild and vaccines being harmful are magnified by reporting bias. It is therefore very important that there is solid epidemiological surveillance to give a high quality evaluation of adverse events of both vaccination and of disease. For example in vaccine safety we would want to know about serious but rare things, even if their rarity makes it difficult to detect. This can be challenging and requires a great deal of funding over years. I agree with many concerned persons who call for more funding for vaccine safety monitoring. Such funding has to compete with more glossy research priorities. A good case example – many countries used to give the live oral polio vaccine (OPV). There is a rare risk that the live vaccine could itself cause polio (this is called Vaccine Associated Paralytic Polio or “VAPP”). In the US this risk was about 1 in 1.4 million. In addition, the vaccine can change genetically and be able to circulate and cause polio (this is called Vaccine Derived Poliovirus or “VDPV”). Between 1988 to 2015 there were 813 documented community circulating VDPV cases identified (half of these were in Nigeria). That is 813 cases in 27 years. Most of the world’s children received this vaccine over the same period, that is millions upon millions of doses. Nevertheless, as polio vaccination rates are high globally and as a result polio elimination is occurring in most countries (but for a few notable exceptions) and the risk from polio drops, so the risk from VAPP and VDPV became unacceptable even though it was tiny. As a result of this changing risk:benefit balance the world is changing from using the live oral polio vaccine to the injectable killed polio vaccine (which cannot cause VAPP or VDPV), this is a gargantuan undertaking. The US already made this change in 2000. Good global surveillance of both polio disease and of polio-vaccine adverse events led to a global policy change, entirely driven by vaccine safety concerns. The vaccine research and policy community takes vaccine safety very seriously. We subject all children to vaccines. We subject our own children to vaccines. We want these vaccines to be safe for our children in the same way that you readers want them to be safe for your children. You love your children at least as much as I love mine, and I love mine just as much as… well actually nobody could possibly love their children as much as I love mine…
Lastly, I would also like to clarify a general point. I stated in my letter that with respect to the question of autism, measles vaccines are entirely safe. I stand by that statement. But after reflection I think it is more prudent to say that in terms of all their other risks for adverse events, that vaccines in general are not entirely safe but that they are very very very safe. Of course adverse events occur. Mild and transient events are ubiquitous and resolve, serious adverse events do occur but very rarely. But the most important point of all to understand is that the risk of NOT vaccinating is far greater than the risk of vaccinating. Not vaccinating will result in a return of infections (like measles as we see now) whose complications are more common and more severe than the adverse effects of vaccines. This is especially the case for measles at the moment since measles cases are presently still occurring. But it will continue to be the case even once measles incidence (i.e. new cases occurring) is hopefully brought under control by the public health authorities. Even then, measles is likely to be reintroduced into the Jewish community from Eretz Yisroel or other places.
May we make good decisions and trust in the Almighty, that we and our children be healthy in order to be le’ovdo be’emes.