On 21 June 2017, the European Court of Justice ruled in favor of the plaintiffs in a case that examined whether Sanofi-Pasteur’s hepatitis B vaccine caused multiple sclerosis (MS) in a patient. Although the ruling might, on the surface, be considered bad for vaccines, we need to look more carefully at that European court vaccine ruling.
There are several questions that we need to answer. First, what did the court actually rule? What can courts say about science? And, is there any evidence that the hepatitis B vaccine causes multiple sclerosis?
European court vaccine ruling
If there is no scientific consensus as to whether a vaccine causes a particular kind of injury, member state courts can allow plaintiffs to use circumstantial evidence to prove a vaccine injured them. Defendants, of course, can use scientific evidence to counter the plaintiff’s circumstantial evidence. This decision does not mean that science doesn’t matter in the courts or that anti vaccine activists can win even when the science is against them.
Member courts cannot treat circumstantial evidence as creating a presumption of causation. The plaintiff bears the burden of proving the vaccine cause the injury, and each case must be examined on its facts. For example, a temporal connection alone does not automatically mean there’s causation.
In a referral like this, the ECJ does not reexamine the facts. It is answering the specific questions of law, and basing its decision on the description of the facts sent up from below. The ECJ was acting on a mistaken premise that the science, in this case, was unclear. That premise came from the lower courts, and the ECJ did not err in following it: it did not reexamine the facts, and did not decide the case in front of it, it only addressed a specific legal question. In the lower courts that now will be expected to rule according to the ECJ’s decision, Sanofi Pasteur – the defendant – should provide the scientific evidence, and we can hope the court, as did the Court of Appeals who ruled on the case last, will follow it. It’s unclear how the case will end.
Let’s be clear. The European court vaccine ruling did not state that the hepatitis B vaccine caused MS in the case of the plaintiff. The court did not review the scientific evidence, but only ruled on a point of law that the member state courts can allow plaintiffs to use “circumstantial evidence to prove a vaccine injured them.”
And the case is far from completed. Essentially, it was sent back to the lower court in France to be retried, and it would be incumbent upon Sanofi-Pasteur to present real scientific evidence that there is no causal link between hepatitis B vaccines and MS.
Despite the breathless proclamations from the pro-vaccine community, solid scientific evidence still matters in these cases. As Professor Reiss concluded in her thorough review of the European court vaccine ruling:
It’s important to reiterate, again, what the European court vaccine decision is not. It’s not a decision that says courts can ignore science. It’s not a decision that should allow anti-vaccine activists to bring counter-science claims, like the claim that vaccines cause autism.
And it’s not a decision that requires all member states to follow the French law. It is a decision that allows, even encourages, member states, in situations of scientific uncertainty in product liability – not just vaccines – to consider other factors, such as temporal proximity of harm to vaccine, and compensate a plaintiff even without clear scientific evidence supporting causation. It’s a break for the plaintiffs, certainly.
But European court vaccine decision is not a blank check to blame vaccines for any problem, and it’s not unreasonable to place the burden of scientific uncertainty, when there are other factors that can support causation, on large manufacturers over consumers.
So, vaccine supporters should not assume that suddenly Europe has lost its way and decided science doesn’t matter in court cases. Nor should the anti-vaccine crowd think that this ruling had the effect of condemning vaccines in any way.
The burden of scientific evidence remains – there has to be reasonable evidence about a claim of harm from vaccines before a court rules in favor of the plaintiffs.
What can courts say about science?
It’s important to state, right up front, that even if this European court vaccine ruling actually stated that hepatitis B (or any vaccine) caused MS (or any adverse effect), and the ruling did not do such a thing, it does not mean that its right. Scientific decisions must always rely on the highest quality and quantity of evidence.
This is a constant bone of contention between pro- and anti-vaccine groups. The former understands scientific principles, and that only high quality published and reviewed evidence counts. The latter thinks that anecdotes and other non-scientific “data” is what should drive the equation.
A court decision is not necessarily scientifically based. One side presents all of the data it can usually in a biased manner. So does the other side. And the jury and judge is required to sort through all of this, remembering that emotional appeals are a huge part of these cases.
But more than that, this court seem to think that correlation was roughly equivalent to causation. To be blunt, that’s not science, and for the court to imply that should be sufficient to say that courts really have not much to say about science.
Basically, the court said that correlation can equal causation. Of course, in some cases, that is true. After all, some correlations do indicate causation. However, as all scientists know, an observation of a correlation is a beginning, not an end. Observed correlations are hypothesis-generating. They are not sufficient to conclusively support a hypothesis. That requires more, a lot more, because correlations alone can be profoundly misleading. There can be confounding factors, such that an observed correlation to one factor (say, factor X) is actually a correlation to another factor (say, factor Y) that happens to be also correlated with factor X. Epidemiologists know this and do their damnedest to account for such confounders.
If courts had control of science, and they suddenly decided that correlation can equal causation, then we need to rewrite a bunch of books in epidemiology and statistics. And the justices of this European court need to be awarded Nobel Prizes for their groundbreaking work in science.
But see, they won’t, because, on the science, the European court was wrong. However, as Professor Reiss pointed out in her detailed review of the case, these judges did not avail themselves of all of the research in the area, and when it was sent back to the lower court in France, the expectation is that better evidence will be presented, and this case wraps up without a finding for the defendants, Sanofi-Pasteur.
Is the hepatitis B vaccine related to MS?
The simple answer is no. There are three meta-reviews, the top of the hierarchy of scientific evidence, that examine the relationship between hepatitis B vaccine and multiple sclerosis, all of which found no correlation or causation:
In each study, the researchers found no increase in risk of developing MS after receiving the hepatitis B vaccine.
The most recent meta review, from Mailand and Fredericksen, examined 15 different clinical studies, and found no evidence of a link between the vaccine and multiple sclerosis. They “found no significant association between MS onset and the HBV vaccine.” Moreover, they concluded that, “none of the studies found an association between relapses and vaccination against hepatitis B virus.”
Three separate meta reviews done over two decades all found the same thing – the hepatitis B vaccine was not related to either the onset or relapse of multiple sclerosis.
I am not sure why this evidence wasn’t presented by Sanofi-Pasteur during the lower court proceedings of this case, because the science is crystal clear with respect to this vaccine.
European court vaccine ruling – summary
First, the court did not actually say that vaccine manufacturers could be found liable despite the evidence. In fact, it was clear that if evidence was available that showed no causal link, it should be considered and be more relevant than circumstantial evidence.
Second, courts are not established or are particularly expert in deciding on scientific matters. Courts do not use the scientific methods to decide cases. And they have a difficult time separating high quality evidence from emotional anecdotes.
Third, the science has spoken on this matter – there is no link between the hepatitis B vaccine and multiple sclerosis.
So, we can be a bit more relaxed about this European court vaccine ruling, even though it’s pretty clear that the vaccine deniers will use it to make some memes that say “Europe says vaccines are dangerous.” We know better.
- DeStefano F, Verstraeten T, Jackson LA, Okoro CA, Benson P, Black SB, Shinefield HR, Mullooly JP, Likosky W, Chen RT; Vaccine Safety Datalink Research Group, National Immunization Program, Centers for Disease Control and Prevention.. Vaccinations and risk of central nervous system demyelinating diseases in adults. Arch Neurol. 2003 Apr;60(4):504-9. PubMed PMID: 12707063.
- Farez MF, Correale J. Immunizations and risk of multiple sclerosis: systematic review and meta-analysis. J Neurol. 2011 Jul;258(7):1197-206. doi: 10.1007/s00415-011-5984-2. Epub 2011 Mar 24. Review. PubMed PMID: 21431896.
- Mailand MT, Frederiksen JL. Vaccines and multiple sclerosis: a systematic review. J Neurol. 2017 Jun;264(6):1035-1050. doi: 10.1007/s00415-016-8263-4. Epub 2016 Sep 7. Review. PubMed PMID: 27604618.