How officials cracked case of eyedrops that blinded people

The patients’ eyes were painfully inflamed. They could sense light but could see almost nothing else. A doctor called one case the worst eye infection he’d ever seen.

It was the beginning of a national outbreak caused by an extremely worrisome bacteria — one that some say heralds an era in which antibiotics no longer work and seemingly routine infections get horribly out of hand.

At last count, 58 Americans in 13 states have been infected, including at least one who died and at least five who suffered permanent vision loss. All have been linked to tainted eyedrops, leading to a recall.

Experts marvel at how disease detectives pieced together the case: Patients were scattered across the country. The illnesses occurred over the span of months. The infections were found in different parts of the body — in the blood of some patients, in the lungs of others.

But scientists also shudder, because they have long worried common bacteria will evolve so that antibiotics no longer work against them.

“This really shows us that it’s not something theoretical and in the future. It’s here,” said Dr. Luis Ostrosky, an infectious diseases expert at the University of Texas Health Science Center at Houston.

This account is drawn from phone and email interviews with U.S. disease investigators, health officials in three states and regulators in the U.S. and India.

The invest igat ion started in May in Los Angeles County, California. A patient who’d recently been to an ophthalmologist came in with a bad eye infection. A month later, local health officials got a second report. Another bad eye infection, same eye doctor.

Two more cases were reported in the county before the summer was over. The patients’ eyes were inflamed with heavy yellow pus that obscured most of the pupil. Among the four, two had complete vision loss in the affected eye.

The hospital that reported the first infection determined it was caused by a bacteria called Pseudomonas aeruginosa. The institution, which was equipped to do advanced genetic testing, quickly realized the bacteria had a rare gene that protected it from the effects of commonly used antibiotics.

It was an early break for investigators, said Kelsey Oyong, of the Los Angeles County Department of Public Health.

Oyong and her colleagues knew they were dealing with a scary germ, and they notified the Centers for Disease Control and Prevention.

Pseudomonas infections are not new. Drug-resistant strains of the bacteria cause more than 30,000 infections annually among hospitalized patients in the U.S. and more than 2,500 deaths, the CDC said. It can spread through contaminated hands or medical equipment, and is particularly dangerous to fragile patients who have catheters or are on breathing machines.

But the California infections were in patients’ eyes, not more common spots like the blood and lungs. Also, the lab analysis determined the infections were caused by a Pseudomonas germ that could resist just about every antibiotic.

The only thing that worked was a newer antibiotic called cefiderocol, administered by IV.

Over the summer, Pseudomonas outbreaks were seen at long-term care facilities in two other states.

In Connecticut, the first case was in June. Eventually, the bacteria was found in 25 patients from five nursing homes in different parts of the state, said Christopher Boyle, a spokesperson for Connecticut’s health department.