Sometimes science does not move fast enough, despite much hard work and effort. That’s true in the case of the Zika virus outbreak currently marching through the Americas. As we report in a collection of stories, much remains unclear, including the relationship between Zika infection and microcephaly and how best to combat the mosquitoes that spread the disease. So far, however, evidence does suggest that this little-known (and previously largely ignored) virus may indeed target the nervous system, probably triggering Guillain-Barré syndrome in a small percentage of patients. The virus could even pose as-yet undiscovered health risks that may take years to untangle. While scientists will no doubt eventually be able to answer many of the public’s pressing questions, it may be too late for many.
It’s not a global emergency, but the public is also apparently impatient with science’s progress on providing practical advice about the human microbiome — the collection of bacteria and other microorganisms that live in and on us. This issue features two articles about new results from this hot field. Laura Sanders details surprising ways that gut microbes can meddle with the brain, hinting that certain microbial mixes may influence depression and other mental disorders. And Meghan Rosen describes the microbiome’s role in malnutrition, suggesting that resetting children’s microbes may be a useful treatment. It’s hard not to conclude that manipulating the bacteria in your body could offer a path to better health and happiness.
Judging from the shelves at Whole Foods, that is what many makers of probiotic supplements would like you to believe. And it may well turn out to be true — studies have linked the microbiome to metabolic and digestive issues such as obesity, irritable bowel syndrome and inflammatory bowel disease. But science hasn’t yet come up with broad recommendations for the best ways to tend your personal microfloral garden. And since the Food and Drug Administration regulates supplements as foods, not as medicines, probiotic pills may vary in quality and even in actual ingredients; makers don’t have to prove that probiotics are safe or effective.
Notably, none of the researchers that Sanders asked while reporting “Microbes and the mind” said that they regularly take probiotic supplements. They also said that any effects on the brain, while fascinating, are probably subtle for most people — otherwise you’d notice a mood change every time you took antibiotics. In Rosen’s story about malnutrition, researcher François Leulier says: “We can envision some therapy solutions, but we’re still at the basic research level.” It’s just too early to start megadosing, he says, even for very sick kids.
To fill in the gap, people look to anecdote. Or, sometimes knowingly, they engage in uncontrolled self-experiments with an N of 1, fueled by the Internet (see the website Quantified Self) and DIY culture. The data gleaned from these personal trials may help individuals, but they can’t answer big questions.
An eager public — and intriguing science — is propelling microbiome research along. Zika research is sprinting after an elusive and mysterious foe, trying to stop the damage from the virus and learn from a vast natural experiment. In both cases, science must move more swiftly if it is to catch up.