By Clare WilsonPeople undergoing heart surgery may be getting infected with a deadly strain of bacteria, spread by machines used to cool blood.The design of blood-cooling machines is flawed, Daniel Diekema at the University of Iowa told the European Congress of Clinical Microbiology and Infectious Diseases in Vienna, Austria, last week. “This was an infection risk that was hiding in plain sight for decades,” Diekema said.The risk arises during open-heart surgery when inserting a device, such as a valve or blood-vessel graft. This process requires a machine to cool and later warm up the blood. During the operation, machines contaminated by the bacteria can blow them out into the operating room, where they can land on the devices to be implanted.It was thought that the microbe, called Mycobacterium chimaera and common in soil and water, was present in only a certain brand of blood-cooling machine, due to factory contamination. But doctors are now reporting that other machines seem to be affected too, and there is no known way of decontaminating them.The problem is causing alarm among doctors worldwide, because M. chimaera infection is difficult to treat. There are 110 known cases of this happening in heart patients so far, and half of those infected have died.
Deadly infection spread by contaminated heart surgery machines