Plague is thought of as an ancient disease, banished by modern medicine. But it never went away and scientists worry another global epidemic could occur due to climate change. Fears have been sparked by three cases in Inner Mongolia, where persistent drought is believed to be behind infestations of rodents carrying infected fleas. But while authorities contend there are no signs of an outbreak, the risks warrant stepped-up health education to prevent diseases spreading from animals to people. The latest case involves a 55-year-old quarry worker who is believed to have contracted bubonic plague from a wild rabbit he caught and ate. Two other people, diagnosed with the more dangerous pneumonic strain of the disease, were already being treated. But while plague has a justifiably fearsome reputation, early detection and treatment with antibiotics eliminates most risks. The possibility of it spreading has been further decreased through people who had contact with those infected being given medicine and monitored. At least six Chinese have died of plague over the past five years. But China is no more at risk than other countries. According to the World Health Organisation, between 2010 and 2015, 3,428 cases were reported worldwide, resulting in 584 deaths. The Democratic Republic of the Congo, Mauritius and Peru are the most endemic nations, although the disease even occurs in the United States, with an average of one death and seven cases annually. Three major epidemics over the past two millennia killed hundreds of millions of people. Most famous was the so-called “black death”, when 50 million perished in Africa, Asia and Europe during the 14th century, but an outbreak in China and India in the late 19th century also claimed 12 million lives, an estimated 2,000 of them in Hong Kong in 1894. The disease has a 30 to 60 per cent fatality rate if left untreated and while an effective vaccine has still to be created, antibiotics are usually effective if patients are diagnosed early. But climate change has raised risks and as during the severe acute respiratory syndrome outbreak in 2003, officials everywhere cannot afford to let their guards down.