She was feeling increasingly desperate when, doing some internet research, she came across the idea of a fecal transplant. In a faecal transplant, the faeces from a healthy person is inserted anally into the colon of another. The idea is that the bugs from the healthy person will restore the microbial balance of the sick one.
Though the concept of a faecal transplant may seem disgusting at first, being infected with C. difficile was far worse, she says. “The indignity of it is profound. You really feel dirty and contagious. You’re just walking around feeling like a freak.” Getting a faecal transplant felt like no big deal after dealing with C. difficile for so long.
Faecal donors, usually a family member or significant other, are screened for infectious diseases such as HIV and syphilis, and for lifestyle patterns that might endanger the recipient, like high-risk sexual activity.
Ruth says she felt different almost immediately after the transplant, done during a colonoscopy, and felt “almost normal” within three weeks. She was able to go off antibiotics at last, and the hopelessness she had felt for months slowly disappeared. Today, her hair has grown back, and she has recovered fully.
Her doctor, Lawrence Brandt, professor and emeritus chief of gastroenterology at Albert Einstein College of Medicine in New York, has been doing faecal transplants since 1990. He says he is struck by how successful, inexpensive, and apparently safe the procedure is – with no major adverse reactions reported. His research, some of it still unpublished, suggests faecal transplants have been 91% effective in several hundred cases worldwide. There has not yet been a gold standard, double-blind, placebo-controlled study of transplants, but there is a growing consensus that faecal transplants are a good idea for people with persistent C. difficile infections.
Someday, he predicts, the procedure will be tested and used against many more ailments, too. And eventually, drug companies will figure out how to bottle the right bacteria, and faecal transplants will not be necessary, he says. “Today, we use stool, because we haven’t yet worked out the precise formulaic combinations of organisms that are deficient in each of the diseases we are talking about.”
Faecal transplants, of course, are not the only way to change gut microbes. As Ruth experienced, antibiotics – particularly repeated courses close together – can alter the balance, as can serious illness and shifts in diet. A gene might leave you more or less vulnerable to a bacterial hit, says Huttenhower. “If you’re predisposed and your microbial community by chance enters a high-risk state, those factors could combine to trigger disease.”
For the most part, the populations you have in early childhood will be with you the rest of your life. Even after microbe populations are disrupted by antibiotics, they tend to return to a baseline, says Graham Rook, emeritus professor of medical microbiology at University College London.
Different events, particularly early in life, can affect that baseline. A study published last year found that babies delivered by C-section had different gut microbes than those delivered vaginally – presumably because they were exposed to different bugs on their path out. MetaHIT’s Ehrlich points to other research suggesting that a baby’s microbe population changes continuously, until around two years of age, so it is not clear whether this early difference – or any microbial change in early childhood – has any long-term health implications.
Researchers believe that the microbes of people who live together can begin to resemble each other. “You’re going to share more with each other than you would compared to someone living in Chicago, but still retain a lot of a history of who you are and where you’ve been,” says Gary Huffnagle, an immunologist and professor of internal medicine at the University of Michigan. “The longer you cohabitate, the theory is, the more you’ll begin to look like each other.”