Four types of gut bacteria may reduce a child’s risk of developing asthma according to a recent Canadian study.
Most Infants - but not all - typically receive these bacteria from their environment or mothers after birth. Sometimes babies are given antibiotics that not only kill bad bacteria, but eliminating the helpful gut bacteria as well.
"We now have particular markers that seem to predict asthma later in life," lead researcher Brett Finlay, a professor of microbiology and immunology at the University of British Columbia in Vancouver, said during a news conference Tuesday.
"These findings indicate that bacteria that live in and on us may have a role in asthma," he said. This seems to happen by 3 months of age in ways that still aren't clear.
Previous studies have shown that certain environmental bacteria, such as living on a farm or having pets, appear to decrease the chances of children developing asthma.
Another interesting clue to asthma is what populations seem to have the most cases. Instances of asthma have increased in western countries where hygiene standards are higher. "Ironically, it has not increased in developing countries," Finlay said.
Organizations that specifically track asthma cases around the world say that as developing countries move from poverty into low-to-middle income, cases of childhood asthma begin to increase.
The "hygiene hypothesis," says environments that are too clean may actually impede development of the immune system.
For the study, Finlay and colleagues looked for four types of bacteria in stool samples of 319 infants at 3 months of age. The bacteria are called FLVR (Faecalibacterium, Lachnospira, Veillonella and Rothia).
The researchers found that 22 children with low levels of these bacteria at age 3 months also had low levels at age 1 year.
These 22 children are at the highest risk of developing asthma, and eight have been diagnosed with the respiratory disease so far, the researchers said.
Study co-author Dr. Stuart Turvey, professor of pediatric immunology at the University of British Columbia, said at the news conference that it's "not surprising how important early life is."
In the first 100 days of life, gut makeup influences the immune response that causes or protects kids from asthma, he said.
Turvey also noted that testing infants for these bacteria might help identify children who will be at high risk for asthma. Babies without FLVR bacteria could be followed and treated earlier for better outcomes he said.
Whether giving kids probiotics -- good bacteria -- might reduce asthma risk isn't known, the researchers said. Turvey said the probiotics available in over-the-counter forms do not include the four bacteria identified in this study.
"Studies like ours are identifying specific bacteria combinations that seem to be missing in the children at the highest risk of asthma," he said. "The long-term goal is to see if we could offer these bacteria back, not the general nonspecific probiotics."
Finlay said the findings need to be replicated in larger groups and in different populations. He said the researchers also want to know if all four bacteria are protective, or just one or two.
As with most studies, the results did not prove a cause and effect only a connection, in this case between gut bacteria and asthma risk in children.
The report was published online in the journal Science Translational Medicine.
Source: Steven Reinberg, http://www.webmd.com/parenting/baby/news/20150930/gut-bacteria-tied-to-asthma-risk-in-kids