Just a quick update on Zika:
A case-control study in French Polynesia has found a strong association between Zika infection and Guillain-Barré Syndrome (GBS). That is, the proportion of cases of GBS who had previous Zika infection (confirmed by serological analyses) was significantly larger than the proportion of people without GBS who had previous Zika infection. Of course, a case-control study is not definitive; it doesn’t prove causation. But it’s a strong relationship and the study is very sound.
A letter published in The Lancet talks about fetal brain damage and microcephaly in fetuses whose mothers were infected with Zika. The virus was detected in amniotic fluid and in the brain tissue of aborted fetuses. In fact, the brains of the fetuses (four fetuses) were not developing normally. Just like with the case-control study, these findings are not definitive, but they also continue to pile-on the evidence for a Zika-microcephaly link. (Still no connection between the “Monsanto Larvicide” and microcephaly, no matter how much people want to believe. Reality doesn’t care if you believe or not.)
So now we have evidence of neurological disorders associated with Zika infection outside of Brazil, which throws a wrench in the theory that it’s Zika plus some other thing (e.g. Dengue infection). It also throws a wrench in the larvicide theory. It even throws a wrench in the Reptilian Overlords and OMG! Zombies! theories.
This is how science works, by the way. You get a case report or an outbreak, and you work from there. You don’t make enormous leaps to things that are not biologically plausible. You eliminate all the biologically and scientifically plausible things before you move into the really weird stuff. In other words, when you hear hoofbeats, think horses, not zebras. Leave the zebra preparations to the experts. 😉
René F. Najera, DrPH
I'm a Doctor of Public Health, having studied at the Johns Hopkins University Bloomberg School of Public Health.
All opinions are my own and in no way represent anyone else or any of the organizations for which I work.
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