An experimental treatment pioneered by British scientists is helping premature babies survive lethal infections by giving them the right kind of "friendly" gut bacteria.
Early results from an ongoing trial in Norwich involving 240 pre-term infants fed probiotic milk laced with the bugs look "exciting", say researchers.
The aim is to alter the babies' gut microbiome - the population of bacteria that occupy their guts - in an attempt to bolster their defences against infection.
Lead scientist Dr Lindsay Hall, from the new Quadram Institute - formerly the Institute of Food Research - said: "We are trying to change the microbial profiles of these premature babies.
"This research has not yet been published and we are still crunching the numbers, but at the moment the data look really exciting."
Around one in eight babies in the UK are born early, leaving them vulnerable to potentially fatal complications and harmful bacteria.
Each year more than 1,000 of these infants die soon after birth, resulting in heartbreak for their parents.
In healthy babies born after a full nine months of pregnancy, friendly gut bacteria provide a vital first-line defence against potentially deadly microbial invaders.
Research has shown that premature babies have a completely different population of gut bacteria that is far less effective at keeping out the dangerous bugs.
The new study, given the name "Bambi" (baby associated microbiota of the intestine), is targeting necrotising enterocolitis (NEC), one of the most serious infections affecting premature babies.
NEC destroys intestinal tissue, allowing the contents of the gut to leak into the abdomen.
Doctors are unable to save around a fifth of affected infants in the UK, according to research published last year.
Babies undergoing the new treatment being tested at Norfolk and Norwich University Hospitals NHS Foundation Trust are fed breast milk from their mothers or donors containing a healthy mix of gut bacteria.
In particular Dr Hall's team is seeking to raise levels of microbes from the Bifido group, which are known to be lacking in premature infants.
Speaking at a briefing in London, Dr Hall said: "Looking at rates of necrotising enterocolitis before these probiotics were introduced to these premature babies, there seems to be a reduction in overall rates.
"This still needs to be confirmed, but our analysis seems to link a reduction in that disease with a change in the microbial community that's present in these premature babies."
Asked if the findings were significant, she said: "They look positive."
Why premature babies have the "wrong" kind of gut bacteria is not completely clear but may be linked to intensive care conditions, the immaturity of their undeveloped guts, and the fact that many of them are born by Caesarean section.
The next step for the researchers will be a much larger multi-centre UK trial, said Dr Hall.
She added: "We want this to be applicable to premature babies across the UK or even globally."