Infants with four "good" gut bacteria unlikely to have asthma: study

Infants can be protected from getting asthma if they acquire four types of "good" gut bacteria by three months of age, a study based on over 300 families from across Canada said Wednesday.

"This research supports the hygiene hypothesis that we're making our environment too clean," said Brett Finlay, professor at the University of British Columbia and co-lead researcher of a paper published in the U.S. journal Science Translational Medicine.

"It shows that gut bacteria play a role in asthma, but it is early in life when the baby's immune system is being established," Finlay added.

The discovery opens the door to developing probiotic treatments for infants that prevent asthma and could also be used to develop a test for predicting which children are at risk of developing asthma, they said.

Asthma rates have increased dramatically since the 1950s and now affect up to 20 percent of children in developed countries, but ironically they have not increased in developing countries or poorer countries.

In the new study, researchers analyzed fecal samples from 319 children involved in the Canadian healthy infant longitudinal development study.

Analysis of the gut bacteria from the samples revealed lower levels of four specific gut bacteria in three-month-old infants who were at an increased risk for asthma.

Most babies naturally acquire these four bacteria, nicknamed FLVR, or Faecalibacterium, Lachnospira, Veillonella and Rothia, from their environments, but some do not, either because of the circumstances of their birth or other factors, they said.

The researchers also found fewer differences in FLVR levels among one-year-old children, meaning the first three months are a critical time period for a baby's developing immune system.

These findings were confirmed in mouse experiments, which also discovered that newborn mice inoculated with the FLVR bacteria developed less severe asthma.

"This discovery gives us new potential ways to prevent this disease that is life-threatening for many children," said co-lead researcher Stuart Turvey, pediatric immunologist of British Columbia Children's Hospital.

"It shows there's a short, maybe 100-day window for giving babies therapeutic interventions to protect against asthma."

The researchers said that further study with a larger number of children is required to confirm these findings and reveal how these bacteria influence the development of asthma. Endit