Most antibiotic-resistant bacteria are distributed across health centres

Genetic analyses make Europe-wide distribution paths of pathogens visible. Researchers recognized that hospitals are decisive resistant bacteria multipliers.

Transmission in the general population plays hardly any role

Genetic analyses make Europe-wide distribution paths of pathogens visible. Researchers recognized that hospitals are decisive resistant bacteria multipliers.

Almost all known antibiotics are ineffective against extremely resistant bacteria. The number of deaths attributed to infection with such pathogens increased more than sixfold in Europe between 2007 and 2015. How these bacteria spread is described in a study published in the journal Nature Microbiology by an international group of researchers led by scientists from the University Hospital of Freiburg (in German: Universitätsklinikums Freiburg).

According to the study, hospitals and patients’ transfers play a decisive role in the spread of the pathogens. Transmissions from the general population, the environment, agriculture and food play only a minor role.

The closer the hospitals to one another, the more similar the pathogens are

The distribution pathways of extremely resistant bacteria could be traced using detailed genetic analyses. Samples were collected for six months in 455 hospitals in 36 European countries. Based on this representative sample of pathogens, the researchers sequenced the entire genetic information of almost 2,000 bacteria of the species Klebsiella pneumoniae. "The genetic differences between extremely resistant isolates increased the greater the distance between the hospitals was," said Prof. Dr. Hajo Grundmann, head of the Institute for Infection Prevention and Hospital Hygiene at the University Hospital of Freiburg and one of the study authors.

In contrast, the majority of genetically similar isolates came from patients who were treated in the same hospital during the observation period. "Our observations suggest that extremely resistant bacteria spread mainly within individual hospitals and when patients are transferred between geographically near hospitals," said Grundmann.

Good hospital hygiene can control the spread of pathogens

On the other hand, the pathogens only spread sporadically across national borders. Nevertheless, individual international transmissions resulted in nationwide outbreaks. "It is extremely important to ask patients about previous hospital stays at home and abroad when they are admitted," Grundmann notes. Such surveys allow risk patients to be identified, diagnosed early and, if necessary, isolated in order to prevent the spread of pathogens. "We are optimistic that good hospital hygiene will not only delay the spread of these pathogens but will also enable us to control them successfully," says Grundmann.

Epidemic of carbapenem-resistant Klebsiella pneumoniae in Europe is driven by nosocomial spread'.
Sophia David, Sandra Reuter, Simon R. Harris, Corinna Glasner, Theresa Feltwell, Silvia Argimon, Khalil Abudahab, Richard Goater, Tommaso Giani, Giulia Errico, Marianne Aspbury, Sara Sjunnebo, the EuSCAPE Working Group, the ESGEM Study Group, Edward J. Feil, Gian Maria Rossolini, David M. Aanensen & Hajo Grundmann.
Nature Microbiology (2019)
DOI: 10,1038/s41564-019-0492-8