Our bodies are home to more bacterial cells than human cells. These bugs are collectively known as our microbiota. But when we're born, we have very few. Max Vento studies how infants amass their community of bugs and what effect being born preterm has. And it's the subject of a review, in which he and his colleagues also outline how the microbiota of preterm babies can be impaired, and how to coax it into health.

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