Antibiotics given to infants negatively affect the gut microbiome reducing volume and diversity of the gut bacteria and increasing risk of asthma and allergies later in life, according to a study (1) published in JAMA in January 2020.
Early Antibiotics effects prove long-lasting
The administration of early antibiotics was shown to be linked to food allergies, asthma and skin problems, and occurred with all types of antibiotics analysed in the study – penicillin, cephalosporin, sulfonamide or macrolide. The effects worsened as the infant had more types of antibiotic, according to Sidney E. Zven, Uniformed Services University of the Health Sciences, Bethesda, Maryland, and colleagues.
Over 800,000 children of the armed forces were followed for the study. 664 710 children (83.3%) were prescribed no classes of antibiotic, 109 341 children (13.7%) were prescribed 1 class, 20 358 (2.5%) prescribed 2 classes, 3,543 (0.44%) prescribed 3 classes, and 474 children (0.06%) prescribed 4 or more classes during the first 6 months of life.
Paediatric experts expressed surprise at these results which seems rather worrying as there has been previous research showing much the same result.
For example, a study in Canada (2) showed that children who avoid asthma have four strains of bacteria in their gut. These are faecalibacterium, lachnospira, veillonella and rothia. Research on three month old babies that went on to develop asthma by the time they were three years of age was clear. More than 300 babies were followed during the study.
Researchers said the four bacteria accumulate in sterile baby as it passed through the birth canal in natural birth, and were likely to be reinforced through breast feeding.
However, these bacteria could be lost in just one course of antibiotics. Children who had been given antibiotics before the age of 1 had a much higher risk of asthma.
The researchers concluded that the first 100 days of a baby’s life were critical and that natural childbirth, breast feeding and antibiotic use were the three crucial factors that, if not understood, could lead rapidly to the ‘life-threatening’ disease.
As long ago as 2011 there was a 20 study meta-analysis (3) showing that infants who took antibiotics during the first year of life were 50% more likely to develop asthma by age 18. Reducing other drug variables can bring this figure down to 13%. The study also showed a similar risk for the child where the mother took antibiotics during pregnancy.
CDC makes unnecessary antibiotic prescribing a national priority
All this comes at a time when America’s Centers for Disease Control and Prevention estimates that 37% of all antibiotic use in hospitals ‘may be inappropriate’. The CDC states that reducing unnecessary antibiotic prescribing is now considered an ‘urgent national priority’ (4).
In the United States in 2019 there were 1.8 million emergency department visits and 400 000 hospitalisations due to asthma.
2. Science Translational Medicine (Sept 30th)