Experts are marveling at how U.S. disease detectives figured out how eyedrops were linked to dozens of infections. Some nasty eye infections in California led health officials to link a superbug bacteria to potentially contaminated eyedrops imported from India. At last count, 58 Americans in 13 states have been infected. At least one died and at least five suffered permanent vision loss. All were blamed on tainted eyedrops, leading to a recall. Scientists have long worried common bacteria will evolve so that antibiotics no longer work against them. Experts say there is a growing list of bugs that are getting harder to treat.