Two Australian late-breaking abstracts on show at the European Respiratory Society’s (ERS) International Congress have shed further light on the link between microbiota and the development of allergies.
The findings of one study indicate that strategies to protect or support microbial diversity in breast milk could reduce the risk of allergies in breastfed children.
The trial presented by Associate Professor Caroline Lodge, Principal Research Fellow, Allergy and Lung Health Unit, Melbourne University, found that the composition of the colostrum microbiome was different for children who had a clinical allergy and sensitisation.
Breastfed children with persistent clinical allergies had consumed colostrum with a higher abundance of Veillonella, Rothia and Acinetobacter bacterial genera, the analysis showed.
The team also found that greater alpha diversity (richness within a single sample) in the colostrum microbiome was linked with significantly reduced odds of later aero sensitisation. However, no such association was seen for beta diversity (ratio between regional and local species diversity).
Maturity of infant gut microbiome linked to wheeze risk
In a separate study presented by Dr Yuan Gao, Associate Research Fellow at the School of Medicine, Deakin University, Australia, infants with more mature bacterial communities in their gut were less likely to develop atopic wheeze during early childhood.
For this research, the team collected faecal samples from 1,074 babies from the Barwon Infant Study (BIS) at one month, six months and one year. It assessed for atopic wheeze at one year and four years through parent-reported history and skin prick tests to determine allergic reactions to foods or airborne substances.
The team then used DNA sampling in a random cohort of 323 children to characterise the gut microbiota and calculated microbiota-by-age z-scores (MAZ) at each time point to represent microbial maturation over the first 12 months of life.
They found that each standard deviation rise in MAZ at one year of life decreased the chances of atopic wheeze at one year (OR=0.51; 95%CI (0.36, 0.71); p<0.001) and four years of age (OR=0.52; 95%CI (0.31, 0.87); p=0.014).
A new clinical trial called ARROW is now planned to assess whether young children can be given a mixture of dead bacteria to help protect against respiratory illnesses such as wheezing or asthma. The trial aims to enrol 2,000 children from Australia and New Zealand.