The microbiome – the trillions of microbial communities that inhabit our bodies – has been with us always, but it is only relatively recently that we have discovered the close links between healthy microbiota and a healthy human.
To Professor Rogers the connection is unsurprising, so close is our relationship with the microbes that live on the skin and throughout our digestive tract.
“It's really symbiosis in a true sense,” Professor Rogers says. “These organisms have been picked up from the environment, live in a nice, warm, protected world of, for example, the gut. They have functionality, which is shared with our own genetic material, and this means that over time, if we have mutations in our own genes that cause us to lose the ability to make certain vitamins, for example, we can get those from the microbes in our gut.”
As those relationships develop, they create ties that bind us together – we need them and they need us.
“Those organisms become increasingly specialised to living on, or in, us and lose the ability to live outside of it,” says Professor Rogers, “so our fates become completely intertwined and rather than being separate entities, we are really one sort of metaorganism.”
For millennia this system operated without anyone noticing.
“Fast forward to the 17th and 18th centuries and the emergence of microbiology at a time when what killed people overwhelmingly was infectious diseases,” says Professor Rogers. “So we needed to devise a system to identify individual pathogens amongst all of this noise.”
And that’s what we did, cultivating colonies of bacteria in agar plates, studying them and learning how to eradicate or at least control them.
But the whole relationship between us and our microbiomes began to change in the second half of the 20th century.
“We got clean water, we got antibiotics, we got vaccines and for the first time in human history, we took control of infectious diseases to a large extent,” says Professor Rogers.