1. Methicillin resistant Staphylococcus aureus (MRSA) in the Nordic countries Petter Elstrøm Advisor Norwegian Institute of Public Health

2. Objective Prevent establishment of MRSA in hospitals Increased rate of MRSA enforce changes in empiric treatment of S. aureus-infections Changes in antibiotic-guidelines will lead to more resistant bacteria and increase the cost

3. Historical overview Penicillin G introdused in 1941 Penicillin resistant ( -lactamase prod.) S.aureus isolated in 1942 Meticillin introdused in 1959 as the first -lactamase resistant penicillin Meticillin resistant S.aureus first described in 1961 In late sixties MRSA was identified as a nosokomial pathogen In late nineties reduced sensitivity against Vancomycin (VISA) was reported Vancomycin resistant S.aureus (VRSA) isolated in 2002

4. First MRSA-wave Meticillin resistant first described in 1961 Worldwide spread of a single arcaic clone Second MRSA-wave Outbreaks in hospitals 5 dominant clones Third MRSA-wave CA-MRSA Evolution of old clones Continually new MRSA-strains discovered Historical overview

5. CA-MRSA Both epidemiological and microbiological definition Increased incidence among people outside hospitals Young people with no known risk factors for MRSA Differ genetically from strains inside hospitals –SCCmec IV, PVL Less resistant Mainly skin- and soft tissue infections Occasionally severe infections (necrotizing pneumonia)

6. Changed epidemiology Earlier: –Imported cases –Related to hospital admission or employment Now: –Most domestic cases –Increasing rate of cases not related to hospitals –Often no known risk factors for MRSA –Outbreaks in nursing homes

7. MRSA in western Europe Source: www.earss.rivm.nl Proportion of invasive isolates resistant to methicillin 2003

8. MRSA in England og Wales Proportion (%) of MRSA i blood culture, 1989-2002

9. MRSA in the Nordic countries *Estimated for 2005 Source: http://www.srga.org/SSAC/doc/2005/SSAC_MRSAreport_2004.pdf

10. MRSA in Denmark Distribution by place of transmission Source: Robert Skov, State serum institute, Sept. 2005

11. MRSA i Danmark Distribution by age group, 2003 Source: Robert Skov, State serum institute, Sept. 2005

12. MRSA in Sweden 2003 2004 Source: Otto Cars, Smittskyddsinstitutet, sept. 2005 Distribution by place of transmission

13. MRSA in Norway No. of cases, 1995 – 15.nov. 2005

14. MRSA in Norway Proportion by county, 2004 - 2005

15. MRSA in Norway Distribution by place of transmission

16. Hospitalized: MRSA in Norway Distribution by place of infection onset

17. Reported outbreaks in health care institutions MRSA in Norway

18. 2003: 2 hospitals, 3 nursing homes 2004: 2 hospitals, 4 nursing homes 2005: 8 nursing homes

19. Challenges Increasing incidence of MRSA Changing epidemiology Bacterial evolution Laboratorial methods are not optimal Lack in knowledge Differs in national and regional guidelines Compliance of infection control measures are not optimal

20. Actions Coordinate the guidelines in the Nordic countries Discuss and coordinate advices and guidelines in Norway Better survey through genotyping of all isolates Continue rational use of antibiotics Science High quality in hygiene and other infection control measures