Researchers have found that two-thirds of the birds breeding in poultry farms in Punjab carry extended-spectrum beta-lactamase or ESBL enzymes that are resistant to most penicillin and cephalosporin-based antibiotics.

The study was done on 18 poultry farms in Punjab where approximately 50,000 birds each are being raised. Of the birds tested randomly, 87 per cent carried the superbug. The poultry in these farms was meant for meat consumption, the study published in the Environmental Health Perspective journal has said.

ÂThis study has serious implications, not only for India but globally, said study author Ramanan Laxminarayan, director at the Center for Disease Dynamics, Economics & Policy in a statement. ÂWe must remove antibiotics from the human food chain, except to treat sick animals, or face the increasingly real prospect of a post-antibiotic world, he said.

Of these 16 farms which were surveyed, the owners used medicines to treat sick birds and to prevent diseases while two-thirds used the drugs to spur chick growth. The drug use was compared with the levels of resistance present in 1,556 E.coli specimen collected from more than 500 birds.

Chicken is the most consumed meat in India, particularly among the younger generation, and is cheaper as compared to meats. Its consumption is growing annually.

Samples from the farms, which reported using antibiotics, were three times more likely to be multidrug-resistant than samples from farms that did not use antibiotics to promote growth, the researchers said.

The team found reservoirs of resistance across both types of farms but meat farms had twice the rates of antimicrobial resistance than egg-producing farms as well as high rates of multidrug resistance. The study also found high levels of multidrug resistance, ranging from 39 per cent for ciprofloxacin, used to treat endocarditis, gastroenteritis, cellulitis and other infections, to 86 per cent for nalidixic acid, a common treatment for urinary tract infections.

 ÂOur findings suggest that antimicrobial use for growth promotion promoted the development of reservoirs of highly resistant bacteria on the studied farms, with potentially serious implications for human health, Laxminarayan and colleagues wrote in the study.

Farmers who handle the birds often wear open-toe shoes, providing Âa conduit of entry for resistant bacteria and resistance genes into the community and hospitals, where further person-to-person transmission is possible, the authors said. Withdrawal of non-therapeutic use of agricultural antimicrobials in India would be prudent to protect public health, they added.

Easy access to antibiotics, indiscriminate use and lack of awareness about antibiotic use are major issues in India and is approaching epidemic proportions. Estimates suggest more than 56,000 newborns die every year in India because of blood stream infections that cannot be cured by first-line antibiotics.