Canadian researchers hope that their work will lead to a test to identify at-risk infants.
“It shows there’s a short, maybe 100-day window for giving babies therapeutic interventions to protect against asthma,” study lead co-author Professor Stuart Turvey, Pediatrics Professor at the University of British Columbia, told ABC news.
The protection appears to revolve around four key bacteria, the research published in Science Translational Medicine says.
The study also suggests that increasingly germ-free home environments have fuelled a rise in asthma rates in the West since the 1950s.
The researchers analysed stool samples collected at age three months and one year of 319 children participating in the larger Canadian Healthy Infant Longitudinal Development (CHILD) study.
The study showed lower levels of four specific gut bacteria – Faecalibacterium, Lachnospira, Veillonella and Rothia – in three-month-olds who were later found to be at an increased risk for asthma.