This story will be updated as more information becomes available.

An extensively drug-resistant bacterial strain is spreading in the US for the first time and causing an alarming outbreak linked to artificial tears eye drops, according to an alert released Wednesday evening from the Centers for Disease Control and Prevention. So far, the germ has caused various infections in 55 people in 12 states, killing one and leaving others hospitalized and with permanent vision loss.

Infected patients reported using more than 10 brands of artificial tears collectively, with some patients using multiple brands. But the most common brand used among the patients was EzriCare Artificial Tears, a preservative-free product sold by Walmart, Amazon, and other retailers.

No recalls have been announced by the Food and Drug Administration, but the CDC recommends clinicians and patients stop using EzriCare Artificial Tears products pending additional guidance from CDC and the FDA. The manufacturer of EzriCare Artificial Tears announced that it plans to recall the product, which is also sold as Delsam Pharma’s Artificial Tears.

Formidable foe

The culprit behind the outbreak is a strain of Pseudomonas aeruginosa, an extremely versatile, innately drug-resistant bacterium that lurks in the environment, particularly freshwater. It is known to cause various skin, wound, burn, lung, and systemic infections. It most often strikes people in immune-compromised states, such as those with cystic fibrosis, and has a reputation for sparking outbreaks in health care settings, particularly among people with indwelling devices, like catheters and breathing