Scientists Study Antibiotic Resistance

Australian scientists are using pigs to better understand how antibiotic-resistant bacteria persist in hospital intensive care units.

Researchers at the New South Wales Department of Primary Industries note each time an antibiotic is used, entire microbial communities are eliminated.

Antibiotics do not just eliminate bad bacteria, said study leader James Chin. They also maintain a pool of antibiotic resistance genes within the microbial community of patients treated with antibiotics.

Chin, Toni Chapman at Australia’s Elizabeth Macarthur Agricultural Institute and colleagues examined how pigs infected with E. coli bacteria respond to antibiotics.

Our research shows clearly that use of one antibiotic to treat E. coli not only increases resistance against that antibiotic but also increases the carriage of resistance genes against other classes of antibiotics, said Chin. This creates a real problem because subsequent therapy with a second antibiotic may be ineffective because resistance against the second antibiotic had already been increased by the first antibiotic.

Chin said it’s important to develop a molecular detection method that can rapidly identify antibiotic resistance signatures of entire microbial communities.

He presented the research last month in Adelaide, Australia, during the annual meeting of the Australian Society for Microbiology.