Asthma rates have increased dramatically since the 1950s and now affect up to 20 per cent of children in western countries. In children ages 5-14 years, the rate of death from asthma almost doubled between 1980 and 1993. The disease is more common in blacks and in city-dwellers than in whites and those who reside in suburban and rural areas. A US government survey showed that among children aged 0-4 years in 1993, blacks were six times more likely to die from asthma than whites. Among children aged 5-14, blacks were four times more likely than whites to die of the illness. Effective medicines are available, however a child’s response to treatment is currently unpredictable.
Now, a study from researchers at UBC and BC Children’s Hospital has shown that infants can be protected from getting asthma if they acquire four types of gut bacteria by three months of age. The team state that 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.
Previous studies show that allergic children have a different intestinal flora from healthy children, with higher levels of Clostridia and lower levels of Bifidobacteria found in allergic children’s tummys. Bifidobacteria and Lactobacilli are found more commonly in the composition of the intestinal flora of non-allergic children. Probiotics are ingested live microbes that can modify intestinal microbial populations in a way that benefits the host and they are represented mainly by Lactobacilli. Enhanced presence of probiotic bacteria in the intestinal microbiota is found to correlate with protection against atopy. There is also very promising evidence to recommend the addition of probiotics to foods for the prevention and treatment of allergic diseases with changes in the gut microbiota implicated in the development of asthma in animal models. However, it has remained unclear whether these findings hold true in humans.
The current study investigated more than 300 families from across Canada, through the Canadian Healthy Infant Longitudinal Development (CHILD) Study. The lab analyzed fecal samples from 319 children involved in the CHILD Study. Results show that 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. The group explain that most babies naturally acquire these four bacteria, nicknamed FLVR (Faecalibacterium, Lachnospira, Veillonella, Rothia), from their environments, however some do not, either because of the circumstances of their birth or other factors.
The data findings also show 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. The team confirmed these findings in mice and also verified that newborn mice inoculated with the FLVR bacteria developed less severe asthma. The lab conclude that it shows that gut bacteria play a role in asthma and it is early in life when the baby’s immune system is being established.
The team surmise their findings gives the global medical community new potential ways to prevent this disease that is life-threatening for many children. They go on to add that they have shown there’s a short, maybe 100-day window for giving babies therapeutic interventions to protect against asthma. For the future, the researchers plan further study with a larger number of children to validate these findings and reveal how these bacteria influence the development of asthma.
Source: University of British Columbia