Tuesday, December 4, 2012

Antibiotic resistance passes to soils

Animal antibiotic resistance passes in their urine to soil and then gives rise to antibiotic resistance among people, claims a new study from Washington State University.

They studied cephalosporin which contributes to antibiotic resistance in humans.

Seven months ago, the United States Food and Drug Administration curbed the use of the drug by issuing new rules on extra-label prescriptions for cattle, pigs, chickens and turkeys.

Cephalosporins came to market in 1964.

Although bacterial resistance to cephalosporins has long been studied, and researchers knew it doesn’t develop in an animal’s gut, they didn’t know how it spread until the researchers at Washington State University decided to examine soils.

“Even short-term persistence in soil provides [an] advantage to resistant E. coli populations, resulting in significantly prolonged persistence of these bacteria in the soil,” the researchers say in this month’s issue of the journal PLOS ONE.

They found that — especially in warm weather — a variety of bacteria may develop resistance within 24 hours, including E. coli and salmonella. Newer cephalosporins on the market are used to treat salmonella and shigella, especially in children.

In animal agriculture, cephalosporins are used to treat bacterial pneumonia in pigs and cattle and to control early mortality in chicks and turkey poults. The FDA had singled out the use of ceftiofur in dairy cattle as a concern, saying dairy farmers often fail to keep required records.

In the Washington State study, the researchers suggest that on-farm interventions —such as bioremediation, the addition of adsorption agents or improved waste management — may help stem the rise of antibiotic resistance.