It was late last summer when Dr. Guillermo Amescua began to notice «something weird» about the eye infections he was seeing in his clinic.

Amescua, a corneal specialist at the Bascom Palmer Eye Institute at the University of Miami Miller School of Medicine, was well aware of the use of antibiotics to treat bacterial eye infections. Miami’s warm climate, he said, often convinces people to relax by the pool or beach before removing their contact lenses, breeding bacteria: pseudomonasmostly, a perfect breeding ground.

Once infected, patients report that their eyes hurt. They can’t see clearly. They are sensitive to light. Not usually a problem, Amescua said. «We usually take care of that,» she said. «No problem.»

An infected eye.Obtained by NBC News

But his arsenal of antibiotics has stopped working. In the past six months, Amescua said he has found at least seven cases of antibiotic-resistant Pseudomonas bacteria, with devastating results. The new strain is a type Pseudomonas aeruginosa that had never been seen in the US before, according to the Centers for Disease Control and Prevention.

Patients have needed corneal transplants. Some were blinded.

«I was having one complication after another,» Amescua said. «I can’t remember losing so many times in my 10+ years of battling a Pseudomonas infection in such a short time.»

Among the cases nationwide, the CDC says the common thread appears to be a particular brand of eye drops: EzriCare Artificial Tears. The agency urged people to stop using the eye drops immediately.

EzriCare artificial tears.
EzriCare artificial tears.Obtained by NBC News

Most were purchased online, but at least one person reported purchasing the drops at Costco, the CDC told NBC News this week.

Since Wednesday, artificial tears, made in India by Global Pharma Healthcare, have been linked to at least 55 cases of antibiotic resistance pseudomonas infections nationwide. So far cases have been reported in 12 states: California, Colorado, Connecticut, Florida, New Jersey, New Mexico, New York, Nevada, Texas, Utah, Washington, and Wisconsin. The company has since withdrawn its products, also sold under the Delsam Pharma brand, from the market.

One person died and five other people were blinded, in at least one eye, the CDC said. The agency first reported potential issues with the eye drops on January 20, but did not issue a public health alert on the matter until February 1.

«This was a very complex investigation that required a number of techniques that are time consuming and difficult to coordinate and implement,» a CDC spokesperson told NBC News. «Due to the widespread nature of this outbreak, the investigation required coordination and data collection from a large number of state and local health jurisdictions.»

One suspicious case involves Judy Gregory, 81, of Elsmere, Kentucky. Gregory said she used EzriCare Artificial Tears to relieve dry eyes before she was hospitalized with an eye infection on June 1, 2022. Her daughter, Kim Harrison, said her mother’s infection was so severe that her doctors «said it would be a miracle if he could save the eye.»

Fortunately, they did. But eight months later, Gregory says he’s still suffering from vision loss. Harrison still takes his mother to eye appointments because Gregory’s poor vision means she can no longer drive. Gregory said his doctor reported the case to health officials.

While the CDC has not yet definitively traced the infections back to the eye drops, the agency is investigating cases with the Food and Drug Administration and state and local health officials.

The CDC is now testing unopened bottles of EzriCare Artificial Tears to determine «whether contamination may have occurred during manufacturing,» the agency said.

The FDA first learned of the Pseudomonas aeruginosan outbreak in December 2022, a spokesperson told NBC News. At the time, the CDC was investigating many potential products. The FDA learned in January that the Pseudomonas aeruginosa bud was associated with EzriCare Artificial Tears. Over-the-counter eye drops do not require FDA approval.

Darlene Miller, who runs the laboratory at the Bascom Palmer Eye Institute, urged people who may have been infected by the droplets to contact a doctor immediately.

The bacteria, Miller said, «can destroy the eye in 48 hours.»

According to the CDC, symptoms of an eye infection include:

  • Yellow, green, or clear discharge from the eye.
  • Pain or discomfort in the eyes.
  • Redness of the eye or eyelid.
  • Sensation of something in the eye (foreign body sensation).
  • Increased sensitivity to light.
  • Blurry vision.

Meanwhile, doctors like Amescua are concerned that people will continue to use the contaminated eye drops.

«It’s alarming because it has resistance to almost everything we have,» he said.

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