No infections were reported and the risk of death is low, but patients need regular check-ups. Symptoms can take up to 6 years to appear. They include night sweats, muscle aches, weight loss, fatigue, or fever.
Infections are caused by Non-Tuberculosis Mycobacteria (NTM), a type of bacteria commonly found in water. It rarely infects healthy adults, but it resists antibiotics and can cause death — especially if it gets inside the chest of a patient who is having surgery.
Experts believe NTM infections are transmitted by a machine that is commonly used in the operating room during open-heart surgeries.
The machine is a Sorin 3T Heater-Cooler Unit. It uses water to control the body-temperature of a patient who is anesthetized during surgery. Water never directly touches the patient, but it does spray out the back through exhaust vents.
Bacteria in the water can also spray into air in the operating room, land on a patient during surgery, and cause an infection that may not be diagnosed for years.
In 2014, an outbreak of NTM infected 15 patients at Greenville Memorial Hospital in South Carolina. Four of the patients died. The hospital found NTM in their tap water and heater-coolers, but never pinpointed the source of the outbreak. In 2015, the FDA warned hospitals not to use tap water in heater-coolers.
It is likely that nearly everyone who had open-heart surgery in the U.S. since 2006 was exposed to a risk of infection with NTM bacteria — but not because hospitals were using tap water.
Instead, many heater-coolers were contaminated with NTM bacteria at manufacturing facilities in Germany. And although U.S. hospitals have warned tens of thousands of patients, it is possible that millions were actually exposed. Heater-coolers are used in 250,000 surgeries per year.
One recent study focused on a strain of NTM called M. chimaera, and concluded with researchers warning:
We find it likely that most Sorin 3T HCUs made in the past 8-10 years potentially are contaminated by the same M. chimaera strain. In addition, because 80% of the Maquet HCUs also contained M. chimaera … we suggest mycobacterial contamination might be a general problem for HCUs.”
South Carolina is already at the epicenter of the litigation, where 10 out of 15 heater-cooler infection lawsuits are pending. On January 26, lawyers asked judges to create a Multi-District Litigation (MDL) to coordinate all lawsuits nationwide under one judge in South Carolina.