Escherichia coli bacteraemia epidemiological data 2007

Introduction

This report contains data voluntarily reported to the Health Protection Agency for Escherichia coli bacteraemia in England, Wales, and Northern Ireland from 2003 to 2007. These analyses are based on data extracted from our voluntary surveillance database on the 26th February 2008 for the period between 2003 and 2007. The data presented here differ in some instances from data in earlier publications due to the addition of late reports to the database.

• E. coli has overtaken Staphylococcus aureus as the most frequent cause of bacteraemia voluntarily reported by laboratories in England, Wales and Northern Ireland to the Health Protection Agency (1). 
• There was a 9% increase in the total number of reports of E. coli bacteraemia via the voluntary surveillance scheme in 2007 (21,904 reports) compared to 2006 (20,007 reports) (figure 1).
• Since 2003 there has been a 32% increase in E. coli bacteraemia reports, greater than the 24% increase in reports for all bacteraemia (85,354 to 105,928) via the voluntary surveillance scheme during the same time period. The increase may be due to either increased incidence and/or increased ascertainment. Reports for 2007 are provisional as of 26 February, 2008 and are expected to increase due to late reporting.
• E. coli bacteraemia is significantly more frequent among men than women in those aged under one year, and those aged 65 years and over; however E. coli bacteraemia is significantly more frequent among women in the 15 to 44 year age group (figure 2).
• The overall reported incidence of E. coli bacteraemia for England, Wales, and Northern Ireland is 39.5 per 100,000 population. 
• In contrast with analyses in previous years, there have been no significant increases in the rates of non-susceptibility for any key antimicrobials in the past year; however, rates are still 50 to 200% higher in 2007 than they were in 2003 (table 2). 
• The percentage of isolates testing non-susceptibility to either ciprofloxacin or gentamicin remains unchanged from 2006 at 23% and 9%, respectively.
• While the percentage of isolates testing non-susceptible to the extended-spectrum cephalosporins ceftazidime and cefotaxime has not changed since 2006 (12%), this rate is still twice that reported in 2003 (4-5%).  The increased non-susceptibility to cephalosporins since 2003 largely reflects the emergence and spread of strains of E. coli producing extended-spectrum β-lactamases (ESBLs) (2,3).
• All isolates tested for either imipenem or meropenem remained fully susceptible.

 

References

1. HPA. Surveillance of Healthcare Associated Infections Report 2007. London: Health Protection Agency, 2007.

2. HPA. Investigations into multi-drug resistant ESBL-producing Escherichia coli strains causing Infections in England. September 2005. London: Health Protection Agency, 2006.

3. Potz N, Hope R, Warner M, Johnson A, Livermore D. CTX-M-producing Escherichia coli now the dominant cephalosporin-resistant Enterobacteriaceae. Clin Microbiol Infect 2005; 11(Suppl 2):48.

Acknowledgements

These reports would not be possible without the weekly contributions from microbiology colleagues in laboratories across England, Wales, and Northern Ireland, without whom there would be no surveillance data. The support from colleagues within the Health Protection Agency, Antibiotic Resistance Monitoring and Reference Laboratory, in particular, is valued in the preparation of the report. Feedback and specific queries about this report are welcome and can be sent to hcai.amrdivision@hpa.org.uk.

• Age and sex distribution
  Added/updated: 3 July 2008
  
• Antimicrobial resistance
  Added/updated: 3 July 2008
  
• Regional distribution
  Added/updated: 3 July 2008
  
• Trends in reports
  Added/updated: 3 July 2008