Saturday, October 29, 2016

Zika causes birth defects (another case of Moms Across America ignoring science for ideology)

A friend of mine (Iida from Thoughtscapism <FB; website> sent me an interesting story that seems to be gaining steam in the anti-GMO world: Zika doesn't cause birth defects. Before I get started on debunking their claims, it's important to give a proper background on what Moms Across America truly represents and why they are not a valid source of information on anything related to science.

Moms Across America started off as an organization that was opposed to genetically engineered crops (colloquially known as GMOs). They rabidly oppose agrochemicals (glyphosate is a favorite target of theirs) and are well known for outrageous claims that they found glyphosate in X substance. They have claimed to find it in breastmilk, wine, granola bars and more recently vaccines. The group has recently branched out as being opposed to vaccines (although in all fairness, Zen said this was her personal belief and not necessarily the views of the organization), they have acted as a lobby wing and advertiser for organic food, and it now appears to be anti-science in general with their latest post. Researchers have taken the time to look at the methods used in the case of their breastmilk-glyphosate study and even tried to replicate it using proper testing protocols. They have also faced backlash for their attacks on breastfeeding (apparently to help market non-GMO formula, or rather that is what some suggest) and for parent-shaming those who do not "care" enough to feed their kids organic foods. In short, the positions of this group tend to be opposed to science and favor bad science over well designed and accurate studies and science. 

So what does this have to do with Zika and birth defects? In Zen's latest anti-science article she makes a series of claims (sourced from one Ian Trottier) that have no basis in science. She blames the "overblown" hysteria around Zika for allowing $1.9 billion in taxpayer dollars to go to Big Pharma for vaccines and Big Chemical for pesticides. Naturally, in her mind both vaccines and pesticides are far more dangerous than a virus, despite all the evidence to the contrary. First, I'll discuss her "evidence" and the four points that she tries to use to prove that Zika isn't a danger and then I'll discuss what the actual scientific evidence is for Zika causing birth defects (as she wrongly claims that there is no science to back up the idea that Zika causes birth defects). 

In the article, Zen tries to link to several "sources" to claim that Zika doesn't cause birth defects. The first link claims to have all sorts of evidence from science journals that Zika does not cause birth defects. This is what she says about the source: "The website sources articles from the New England Journal of Medicine, Lancet, PubMed, EPA, CDC and others. Additionally, site developer, Ian Hamilton Trottier, has conversed with experts at Lancaster University in the UK and the London School of Hygiene and Tropical Medicine. That includes experts based in the US." However, when you click the link you get the following:

Zen's first source that is "full" of scientific journal articles that "demonstrate" that Zika does not cause birth defects. 
Later in the article, she tries to cite as a source. However, when you click on that link, it is for a domain that is for sale:

Zen's second attempt at linking a source for her claims.

The third source does list the four claims that Zen mentions in her article, but lacks any sources to back up the assertions. 

The fourth time seemed to be the charm as when was linked, you get a website that has some sources. However, every source on that page deals with naled and does not back up the assertions that there is no credible scientific evidence that Zika causes birth defects. Furthermore, Zen claims that Dr. Michael Diamond "is essentially quoted as saying there is nothing that suggests detection of ZIKA as being the actual cause of MICROCEPHALY in the subjects he's studied. Dr Diamond recently published a review that links ZIKA to being present in tear ducts."
Dr. Diamond is indeed a flavivirus expert (the genus that Zika virus belongs to) and has published extensively on Zika (and other viruses and immunology in general). Since I cannot find the quote that Zen is alluding to and the fact that Dr. Diamond's work has been instrumental in confirming the link between Zika and birth defects, one is forced to assume that this quote is from the early days of the Zika outbreak in Brazil, when researchers did not know what we know now about Zika causing birth defects. This is a cherry picked quote that attempts to use an appeal to authority to confirm Zen's ideology despite the fact that the source has clearly demonstrated the opposite of what she is claiming.

The four points of the article basically boil down to "we don't know" and pesticides. She tries to link the use of the pesticides to both Monsanto and the Nazi bombing of France in a clear attempt to poison the well. Pesticides that have been ruled out as being involved with microcephaly, like 
pyriproxyfen, get mentioned as a possible cause. I won't get into that here as I've addressed pyripoxyfen before. It's sort of a rehashing of the claims that Mike Adams made about Zika that I also debunked previously, except Zen mentions paraoxonase as to why naled is really causing the birth defects attributed to Zika. However, her assertion that children have lower levels of paraoxonase in their liver does not automatically mean that the levels of this enzyme are the reason for birth defects. It ignores the fact that the mother's liver will help protect the growing baby. A study did find that lower maternal levels of one of the enzymes in this class did lead to a smaller head circumference, but it was nowhere near the level of reduction seen in babies born with congenital Zika disorder. I don't have the space to get further into the claims surrounding this enzyme as it is complicated.

But what about the evidence that supports the link between Zika infection during pregnancy and birth defects? How solid is the science on this? I'll outline just some of the key findings that support that Zika virus causes birth defects. The body of scientific literature is extensive on this topic and one only has to look to find it.

1) The Zika virus crosses the placental barrier
2) The complete genome of Zika has been recovered from the amniotic fluid and brain tissue of an infected fetus. 
3) Zika virus has been shown to disrupt brain organoid formation and deplete neural progenitor cells in vitro.
4) Case studies have shown a link between congenital Zika infection and birth defects.  
5) Zika virus infection caused birth defects in a mouse model. Specifically the Asian strain is more damaging than the African strain. 
6) A case-control study has demonstrated a clear link between congenital Zika virus infection and birth defects. 

Some of this work has been published since May 2016 when this article summarizing the evidence for congenital Zika virus infection and birth defects was published. This article concluded that the available evidence had met the criteria for a causal link to be established. Since then, the evidence supporting the link has only gotten stronger and at this point attempts to deny the link shows a clear lack of understanding of science. This infographic I made summarizes the evidence for Zika being a TORCH pathogen (TORCH pathogens cause birth defects).

The Zika virus is a TORCH pathogen that causes birth defects.

This article from Zen is a clear cut case of her ignoring the science that clearly demonstrates that the Zika virus causes birth defects. Although to be fair, it's entirely possible that she just doesn't understand the science. Based on her past history, that cannot be entirely discounted; however, not understanding science isn't an argument against it. The real moral here is that people need to be careful what they use as sources. Moms Across America, much like Natural News or Joseph Mercola, have clearly demonstrated that they are not a valid source when it comes to science. They cherry pick quotes and ignore all of the scientific evidence that contradicts their ideology. Moms Across America really shouldn't be used as a source for anything.