Antibiotics in the environment foster child resistance

Exposure to antibiotics at home and in the broader environment influences the risk of children carrying antibiotic-resistant Escherichia coli bacteria, according to a study published in the The American Journal of Tropical Medicine and Hygiene.

The study was based in four areas of Peru with poor health systems, where antibiotics are used indiscriminately and without prescription. It covered coastal, mountain and jungle environments and focused on children between the ages of three months and three years.

The study suggests that environmental exposure to antibiotic-resistant E. colican be as important as the consumption of antibiotics, according to the paper’s principal author, Henry Kalter, from the School of Public Health at Johns Hopkins University.

A risk factor at home was the use of antibiotics by other family members. The study demonstrated that children who hadn’t taken particular antibiotics themselves still carried bacteria resistant to them.

At the community level, living in a place where many families raised chickens themselves was a protective factor against the transport of antibiotic-resistant bacteria. According to Kalter, high consumption of home-raised chickens probably protects a community against exposure to antibiotics. He contrasted home-raised chickens with market-bought chickens, which may be given high doses of antibiotics and therefore have high levels of antibiotic-resistantE. coli.

“An important aspect of our conclusions is that the protective effect was not due to the fact that the children were eating certain types of chicken; rather that their communities were,” he said.

Kalter suggested that communities consuming more chickens raised at home presumably had less resistant bacteria in the environment, such as in open sewers and uncovered wells.

“This study reinforces the message that exposure to antibiotics leads to the development of antibiotic resistance, by studying the role of different types of exposure on small children carrying of antibiotic-resistant E. coli,” he continued.

According to Kalter, examining these factors provides a better understanding of how antibiotic resistance spreads in the developing world.

“These findings suggest that unnecessary use of antibiotics in humans and animals should be minimised as much as possible,” he added.

“Many tons of the antibiotics consumed each year on the planet are given to stock animals. This study demonstrates that this use has a very real cost to human health,” Edward T. Ryan, president of the American Society of Tropical Medicine and Hygiene, said in a press release from Johns Hopkins University.

The study was run by the Johns Hopkins University School of Public Health, the Peruvian charity PRISMA and the infectious disease laboratory of the Cayetano Heredia University in Peru.

The original paper in The American Journal of Tropical Medicine and Hygiene is here.

Translation kindly provided by Cobi Smith.