Monday, March 27, 2017

The acellular pertussis vaccine, the legacy of fear

An infographic I made on the acellular pertussis vaccine

Note: I've decided to go back and post some of my older TMV Facebook page posts as blog posts to preserve them and make them more accessible. I decided to start with the post I made for my infographic on the acellular pertussis vaccine and how we got to that point.
Today's post is a bit different, but I would ask you read my entire post before reaching a conclusion about what I'm saying. Part of being a scientist is following the data no matter where it leads and how uncomfortable it is. With that, I present the case of the acellular pertussis vaccine and how we got to the point we are at now questioning the effectiveness of the vaccine. However, as I point out below, scientists are not the ones responsible for this vaccine that is far less effective at preventing asymptomatic infections, we have the anti-vaccine movement to thank for that. 

The acellular pertussis vaccine has been under heavy scrutiny the last few years and for good reason. Although it is a very safe vaccine, it just isn't nearly as effective as the older whole cell version of the vaccine. There have been several studies questioning the effectiveness of the acellular pertussis vaccine in preventing asymptomatic transmission, including the infamous baboon study that still found that the acellular vaccine provided robust protection against all but asymptomatic infections. New research strongly points to the acellular vaccine preventing serious infection and illness but not in preventing asymptomatic infections. This was the conclusion of a study that found that the genetic variation of pertussis was too great if it was being limited by the vaccine. Coupled with several other reviews, including a Cochrane Review, of how effective the vaccine is at preventing serious and mild cases of pertussis, it appears that asymptomatic infections may indeed be happening in the vaccinated populations. However, intentionally unvaccinated populations are still at a higher risk of pertussis than the vaccinated population.  

But how did we get to this point? By all measures, the whole cell pertussis vaccine is highly effective and offers superior protection compared to the acellular vaccine. Why would we abandon it for an inferior vaccine? It turns out that fear and the birth of the modern anti-vaccine movement caused this. Back in the early 1980s, a television news channel released an "expose" of the whole cell pertussis vaccine and inflated the risks of febrile seizures due to the vaccine. In actuality, the risk of febrile seizures is quite low at 6-8 out of 100,000 kids vaccinated, with risk of the seizures only on the day of the vaccination. However, parents and lawmakers demanded a safer vaccine and as a result the acellular pertussis vaccine was created and released in the early 1990s. It was deemed a success at the time as it is incredibly safe. 

But we sacrificed effectiveness for safety. Even as early as 1999, researchers began questioning the effectiveness of the acellular vaccine compared to the whole cell version. The latest research is the final nail in the coffin as it were for the acellular pertussis vaccine. Does this mean we should scrap the idea of a pertussis vaccine? Of course not. But we need to use science to improve the whole cell vaccine and maybe identify the component (or components) of the whole cell vaccine that induces lasting immunity so that we can generate a safe and effective vaccine.

Sunday, March 19, 2017

Why I won't be participating in the March for Science

The Freedom of Speech painting by Norman Rockwell. Via wikimedia commons.

Let me start off by saying that as a scientist, I firmly believe that scientists should speak more to the public and let our voices be heard. However, I have to join the growing number of scientists who won't be participating in the march. Part of my problem with the group and the movement stems from the fact that it is disorganized and has become co-opted by those advocating for pseudoscience. Others have expressed different concerns about the political fallout from speaking out, to the march becoming a liberal movement rather than sticking to what is important which is science funding being cut, to the march being too political, to the march being a potential trap due to the low levels of support for scientists among those in the lowest tax brackets. Others have weighed the pros and cons of the march and discussed some of the issues surrounding it.

Awhile ago, I commented on a post about the importance of values in science and how morality plays into the scientific method. Ethics in science is incredibly important. I trust that my fellow scientists are being truthful in what they report to the community. People who commit fraud eventually are caught and removed from the profession. There are numerous examples of this, from Andy Wakefield to Olivier Voinnet being caught and disciplined. Retraction Watch chronicles this self-policing and although the system can always be improved, it still works and frauds are eventually outed.

Imagine my surprise when I saw a comment in the group about science in the US being bought and paid for. This type of conspiracy theory had been cropping up more and more in the group as well as other pseudoscience in general. So I commented that I found the idea of scientists being bought and paid for offensive and I felt that type of attitude had no place in a group that was meant to organize scientists to let our voices be heard. I often see the idea that scientists are bought and paid for coming from people that have no connection to science or scientists and this case was no different. I may have been a little curt in my reply where I pointed out that the idea of science being bought and paid for is offensive, but I never would have guessed what the response from other members would have been. I was told that I was being an elitist and snobbish in my tone and that I was being divisive for pointing out that the idea that science as a whole is bought and paid for is offensive. When I pointed out that pseudoscience had no place in a movement for science, I was told that all thoughts and opinions should be given equal footing. This was the point that I left the group.

I've told my concerns about how the march could be co-opted by antiscience groups and weaken the message that was trying to be shared to a few friends of mine. Sadly, this seems to be what is happening to the march as they've recently partnered with the Center for Biological Diversity. On the surface, this seems to be okay; however, this group is rabidly anti-GMO and often repeats bad science when it comes to discussing GE crops. 
Stephan Neidenbach addresses some of these misconceptions here and was the first to point out that this antiscience group is taking part in the march. But this isn't the only questionable group to partner with march. They've also partnered with the Union of Concerned Scientists, a group that is anti-GMO and anti-nuclear power. Another problematic partner is the Center for Science in Public Interest which has problematic positions on artificial sweeteners and food dyes. No, aspartame does not cause cancer and the link of artificial food dyes to hyperactivity is tenuous at best. Earth Day Network is another troublesome partner as they have posted antiGMO stories on their facebook page
There are many other partners that are fantastic scientific organizations, but my fear here is that the event is going to be tainted by the organizations that do not hold science in the same regard. Much like my experience in the main FB group, I wonder if these pseudoscience organizations are being included for "diversity of opinion." If so, it hurts the message that the march is trying to send. Scientific facts are not based on opinion, but rather careful analysis of data that has been collected. Just because someone has a differing opinion, it does not rise to the same level of evidence that a scientific fact does. So trying to be "inclusive" of other opinions is not helpful when trying to advocate for science. After all, some might try and state that human involvement in climate change is a matter of opinion and not scientific fact. Or they might state that differences in opinion mean that vaccines can be dangerous too.

Science is not a buffet where people can pick and choose the parts that they like and disregard the rest. It is a method for examining the natural world and answering how and why things happen. Climate change denial, young earth creationism, anti-vaccine and anti-genetic engineering arguments are not equal to the science on those topics. It's incredibly sad to see a group that purports to be standing up for all science to willingly partner with groups that are antiscience or hold antiscience positions. Although there are many other partners that actively promote all science and I do believe that it's important for scientists to speak, I don't want to add credibility to antiscience rhetoric because let's face it, they are going to use partnering with the march to amplify their own antiscience messages. I just can't be a party to that.