Prenatal antibiotics linked to childhood asthma in Tennessee study

In a large retrospective cohort study, increasing number of antibiotics courses, early timing, and broad-spectrum prenatal antibiotic exposure were associated with increased risk for childhood asthma, researchers reported today in Clinical Infectious Diseases.

In the population-based cohort study, which involved 84,212 mother-child pairs enrolled in Tennessee's Medicaid program from 1995 to 2003, researchers from Vanderbilt University and Louisiana State University looked at prenatal antibiotic exposure and the development of asthma in the children by the age of 6 to fully understand the relationship between the two, and to investigate whether any association was modified by a familial disposition to asthma. A total of 54,141 children (64%) were exposed to antibiotics prenatally. 

Compared with never-exposed children, exposure to prenatal antibiotics increased the odds of childhood asthma by 23% after adjusting for covariates (adjusted odds ratio [aOR], 1.23; 95% confidence interval [CI], 1.18 to 1.28). Prenatal antibiotic exposure was also associated dose-dependently with increased odds of childhood asthma (aOR for interquartile increase of 2 courses [0, 2], 1.26; 95% CI, 1.20 to 1.33). 

Among children exposed to at least one course in utero, the effect of timing at the first course was moderated by total maternal courses. Among women receiving a single antibiotic course, timing of exposure had no effect on childhood asthma risk. Among women receiving more than one course, early exposure of the first course was associated with greater childhood asthma risk. Compared with the use of narrow-spectrum antibiotics only, broad-spectrum-only antibiotic exposure was associated with increased odds of asthma (aOR: 1.14; 95% CI, 1.05 to 1.24).

Although children with asthmatic mothers were more likely to be prenatally exposed to antibiotics, the number of courses and timing of the first course were not significantly associated with childhood asthma development. The significant dose-dependent relationship between the number of prenatal antibiotic courses and childhood asthma persisted only in children whose mothers did not have asthma, as did the significant timing effect of first prenatal antibiotic exposure on childhood asthma.
Jan 29 Clin Infect Dis abstract

Report: Some UK supermarkets still allowing routine antibiotics on farms

A report today from the UK-based Alliance to Save Our Antibiotics has found that a handful of British supermarket chains are still allowing suppliers to use antibiotics routinely in food-animal production.

The Alliance's assessment of the publicly available antibiotics policies of the 10 leading British supermarkets found that 3—Aldi, Asda, and Iceland—have no restrictions on their meat, dairy, and egg suppliers using antibiotics routinely, other than minimum legal requirements.

"It's completely unacceptable that Aldi, Asda and Iceland are putting their customers' health at risk by failing to ban routine antibiotic use," Alliance campaign manager Suzi Shingler said in a press release. "We know that antibiotic-resistant bacteria can pass to people from food produced with high levels of antibiotics and can end up causing infections which are much more difficult to treat. This is why the [World Health Organization] and the [United Nations] are calling for urgent action."

The assessment also found that Iceland was the only supermarket with no publicly available policies and no antibiotic-reduction strategy in place, and the only one not to collect data on its suppliers' antibiotic use. Six of the supermarkets have published some antibiotic use data, but none publish good data antibiotic use by farming system, the report says. 

"If supermarkets are really committed to reducing farm antibiotic use, they should publish antibiotic data viewed by farming system, as this would help all farmers to learn from best practice," said Cóilín Nunan, scientific adviser for the Alliance.

Only two supermarkets—Waitrose and M&S—prohibit their suppliers from using the last-resort antibiotic colistin. The supermarkets covered by the assessment are Aldi, Asda, Co-op, Iceland, Lidl, M&S, Morrisons, Sainsbury's, Tesco, and Waitrose.
Jan 29 Alliance to Save Our Antibiotics 2019 supermarket assessment
Jan 29 Alliance news release