1. NGS Journal Club Mette Voldby Larsen PhD, associate professor DTU-SystemsBiology

2. Paper

3.  A possible MRSA outbreak on a Special Care Baby Unit (SCBU) was analyzed using conventional methods.  Colonized patients from SCBU and MRSA isolates with the same antibiotic resistance profile from patients in other wards or from society were whole-genome sequenced. What was done:

4. Antibiogram profiles Red: Resistant White: Susceptible

5. Epidemiological map of 14 infants from SCBU Possible outbreak? Not the same antibiotics resistance profile – not the same outbreak New case after cleaning? Then they start sequencing… A

6. Phylogenetic tree based on core snps All ST2371

7. Antibiogram profiles Red: Resistant Green: Initially tested as susceptible, but re-testing shows it is resistant White: Susceptible

8. Extended search MRSA isolates with similar antibiotic resistance profiles from other wards are sequenced (retro- and prospectively) = 19 isolates Ten of these are also ST2371

9. Epidemiological map, incl. 10 cases outside the SCBU

10. 154 employees are screened for MRSA – ONE is found positive for ST2371

12. Antibiogram profiles for the later cases

13. Epidemiological map, incl. 11 cases outside the SCBU and one employee.

14. Conclusion WGS performed better for identifying patients and citizens part of the outbreak Identification of the outbreak led to the investigation and the identification of a hospital employed carrier