How Are Superbugs Transferred Between People?

Prof. Andrea Endimiani, MD, PhD, from the Institute of Infectious Diseases at the University of Bern, Switzerland, explains the method by which bacteria carrying the mcr-1 gene are transmitted between people.

Interview Transcript (slightly modified for readability)

“The transmission of bacteria carrying mcr-1 between humans follows the same rules of [the transmission of] other pathogens, like those that produce [Extended Spectrum Beta-Lactamase (ESBL)] or Carbopenemases. If we are in a hospital, and we have a patient [who] is infected or colonized at [the] intestinal level, and is in contact with the [hospital] personnel or directly with other patients, [then the patient] can transmit [the gene] via, for example, the hands. We know very well that we have to wash [our] hands, use gloves, [and so on], to stop the transmission of the bacteria between humans.

It is not important if the original patient with mcr-1 is infected, [the patient] can be only a carrier at [the] intestinal level and can [still] transmit [the gene] to another person [who] can [then either] be infected or colonized. The difference is substantial but epidemiologically not very relevant. In hospitals in western countries, we have many patients [who are] only colonized at [the] intestinal level with superbugs. We have to be very careful when we approach these patients; for example, [we can] put them in isolation to prevent [bacterial] transmission to other patients [who] are not yet colonized.”