When the World Health Organization issued a report last February highlighting the antibiotic-resistant pathogens that posed the gravest public health threats, it capped a disheartening year. A powerful variety of E. coli reached American shores, and a Nevada woman died of an infection untreatable by available antibiotics. While it’s not time to panic, the stakes are high. The U.S. sees about 2 million resistant infections every year, and medical professionals still have no real solutions. …