New research suggests a worrying number of people in China may be infected with bacteria resistant to an antibiotic used as a last resort. Researchers examined more than 17,000 samples from patients with infections of common bacteria found in the gut, in two hospitals in China\u2019s Zhejiang and Guangdong provinces, over eight years. About 1 per cent of those samples were resistant to colistin, often considered the last option in antibiotics. The study, published Friday in journal, is one of the first to document the extent of drug-resistant infections in more than one Chinese province. For decades, mainland China has used colistin in its agriculture industry to speed animals\u2019 growth, but the drug was not used in people. Scientists say the latest work is further evidence that overuse in animals can spread to people. Chinese officials earlier this year approved colistin for use in hospitals, raising fears that it could worsen the resistance problem. \u201cIt will be very important to ration its use so that it\u2019s only used when absolutely nothing else will work,\u201d said Mark Enright, a professor of medical microbiology at Manchester Metropolitan University, who was not part of the research. Health officials have long worried that colistin-resistant bacteria might spread more widely, setting the stage for superbug infections that would theoretically be impervious to medications. Only a small number of such cases worldwide have been detected, including in the United Sates. Rising concerns over drug-resistant germs have prompted the United Nations to encourage countries to cut back on antibiotic use and develop new medicines. People infected with these resistant strains can usually be treated with current antibiotics, but doctors warn that as these bacteria \u2013 which are already untreatable with last-resort drugs \u2013 acquire resistance to current drugs, the infections may become impossible to treat. Experts also noted a surprise: the apparent ease with which the resistant gene spread between bacteria, including different species of bugs. \u201cIt now looks like there\u2019s potential for the resistance gene to move around and spread between different species of bacteria,\u201d said Nigel Brown, a spokesman for Britain\u2019s Microbiology Society, adding that it could lead to a jump in infections. In a separate study also published in , another group of Chinese researchers analysed samples from patients with blood infections at 28 hospitals. About 1 per cent had the colistin-resistant gene \u2013 a much higher figure than would be expected in developed countries. Colistin\u2019s use in hospitals should be restricted to avoid problems, said Yunsong Yu, one of the study\u2019s authors. \u201cThis is a warning shot about the possible scenario where we don\u2019t have very much left in the armoury to treat infections,\u201d Brown said. \u201cI don\u2019t think we are very close to that happening, but it is a remote possibility if we aren\u2019t careful about how we use our antibiotics.\u201d<\/p>\n