In the global cast of drug-resistant bacteria, carbapenemase-producing enterobacteriaceae – more commonly known as CPE – can be thought of as the brooding villains. They are resistant to nearly all antibiotics, they can spread resistant traits to other organisms, and as many as 50 per cent of people who get a serious CPE infection die.
Yet when Fraser Health Authority detected 41 patients carrying the potentially lethal bug in its hospitals in the last half of 2013, it was under no obligation to report that to the public. The reason? In Canada, individual health facilities determine what constitutes an outbreak. Fraser Health has called the incidents a "cluster," saying B.C. hospitals and infection control practitioners are still discussing guidelines on what determines an outbreak.
The question of when a cluster becomes an outbreak – and whether and when the public should be told – is pertinent not only to Fraser Health, which serves more than 1.6-million people in the Fraser Valley east of Vancouver. It highlights the challenges for Canadian hospitals when it comes to getting ahead of CPE, which began to show up in Canada around 2010.
Health facilities are grappling with questions around the best ways to screen and test for the bacteria, the costs associated with increased testing and even whether screening can do harm. A June conference on antimicrobial-resistant organisms in Calgary, for example, includes a session that will discuss whether screening can result in patients receiving reduced care due to "leperization" and isolation.
Fraser Health, meanwhile, is dealing with a new reality – asking patients admitted to its sites whether they have traveled outside Canada within the last six months. Those who answer yes are tested for CPE. The authority currently has about a dozen cases and expects CPE to be an ongoing issue.
"We have not provincially decided on the definition of what an outbreak means," Elizabeth Brodkin, Fraser Health's medical director of infection prevention and control, said last week in discussing the cases. "So I wouldn't use the term outbreak. We saw a cluster, which clearly we needed to respond to. And the measures we put in place were very satisfactory in bringing the numbers down."
British Columbia launched a working group this month to standardize procedures for declaring and managing CPE outbreaks. Other provinces have various monitoring and control programs underway.
Allison McGeer, director of infection control at Mount Sinai Hospital in Toronto, would like to see a nationwide approach to CPE. Dr. McGeer, who co-wrote a 2012 paper on a CPE outbreak involving five patients at a hospital in Brampton, Ont., has no quarrel with Fraser Health's choice of terminology, saying that except in a few cases – such as influenza in nursing homes – the definition of "outbreak" is left open to allow for variation in health-care sites and populations.
But she would like to see uniform CPE reporting requirements across the country – although she concedes that provincial control over health legislation would make that a challenge.
"There is good evidence from Greece and Israel now that making things nationally reportable makes a difference and helps control [CPE]," she said. "These are a threat to public health, they are an important patient safety issue – to my mind, if our legislation is getting in the way of protecting people, then we need to have a serious discussion about changing the legislation."
In the United States, where carbapenem-resistant organisms have been identified in more than 40 states, CPOs are "notifiable" in 13, says Lynora Saxinger, a specialist with the Association of Medical Microbiology and Infectious Disease Canada. "I believe that provinces are evolving an approach as the need arises, and that we still face the problems of appropriate communication nationally," Dr. Saxinger said in an e-mail.
B.C. expects any future CPE outbreaks would be posted on regional health authority websites "in coming months," a Health Ministry representative said Wednesday. That would be in line with reporting guidelines the province put in place last year for C. difficile infections.
CPE become a problem when they move from the gut, where they normally live, to other parts of the body, like the blood or the bladder, where they can cause infections. They are also a threat because they can spread their resistance traits to other bacteria, a particularly worrisome possibility in health-care settings.
"So they're almost a bit like a cluster bomb," said Michael Gardam, an infectious disease specialist at the University of Toronto. "When they go off in your hospital, they're actually spreading resistance genes to multiple different types of bacteria at the same time that they're causing infections."
With a report from James Bradshaw