Drenched in sweat, and unable to keep food down, the small boy must have been as bewildered by the gown-clad hospital staff as they were by him. He had been running a fever, vomiting, and experiencing stomach cramps and diarrhoea for several days before boarding a plane and flying for more than 14 hours back to Canada, after attending a family wedding in Pakistan. Now he was in Toronto Children's Hospital, being assessed by a medical team. "Drug resistance doesn't know borders. With these extremely drug resistant infections emerging, they can go anywhere. They're also very difficult to treat, and have the potential to undermine health systems, even in wealthier countries." Cases of typhoid are uncommon in Toronto, but this case was particularly perplexing, because the bacteria causing the boy's illness appeared to be resistant to almost all antibiotics. Fortunately, the three-year-old's bugs were susceptible to an intravenous antibiotic called ...