A coup for poo: why the world’s first faecal transplant approval matters

Inside your gut is a thriving community of trillions of microbes. Thousands of species of bacteria, viruses, fungi and other microorganisms make up this diverse microbiome, which weighs about 2kg. Its health is affected by your environment and what you eat, and in turn it affects your metabolism, immunity and even your mood.

To be healthy and to keep humans healthy, the microbiome needs to be diverse. That has become an increasing problem in the modern world, where diets are less diverse and get battered by medical treatments such as antibiotics.

In some people, the microbiome has been so badly damaged it needs new microbes to be introduced - for them, a poo transplant can be life altering, even life saving.

The first poo transplant has been officially approved in Australia - in fact, it's the first time a faecal microbiota transplant (FMT) has been given regulatory approval anywhere in the world.

FMT is the process of taking the poo of someone with a healthy gut and inserting it in someone with an unhealthy gut to "repopulate the bacterial microenvironment in a recipient's bowel with healthy microorganisms", according to the Therapeutic Goods Administration.

For now, the only approved FMT therapy is for infection by the Clostridioides difficile bacterium, which used to be called Clostridium difficile and is commonly called C diff. It is an infection of the gut that can be very serious, even deadly.

Dr Sam Forster, an FMT and microbiota expert from the Hudson Institute of Medical Research in Melbourne, says for some people whose gut has been disrupted by antibiotics or other medical treatments, it's as though their internal rainforest (the microbiome) has been razed to the ground. Then the C diff bacterium pops up like a weed and starts producing toxins.