Can we stop the emergence of antibiotic resistance?

Our ability to cure bacterial disease with antibiotics is central not only to the resolution of individual infections but also to the outcome of most surgery and cancer treatment. For over two decades, antibiotic-resistant organisms have grown in prevalence in hospitals, increasing the complexity and costs of hospital-acquired infection. More recently, resistance has also emerged among community-acquired bacteria. Antimicrobial resistance has contributed to a fatal case of community acquired pneumonia in BC (personal communication, Patrick Doyle, MD).

Resistant organisms emerge as a result of natural selection. A principal stimulus is the mass of antibiotics used in human populations. Other factors include the use of antibiotics in agriculture, incomplete treatment of some infections, and importation from abroad. BCCDC has been working with the BC College of Pharmacists to track outpatient consumption of antibiotics and has completed a comparison of BC with European jurisdictions that have similar tracking capability.[1,2] The overall rate of antibiotic use among outpatients in British Columbia has slowly declined from 18.5 to 15.9 defined daily doses per 1000 inhabitant-days between 1996 and 2003. This means that on average, 1.6% of British Columbians are consuming antibiotics on any given day.

BC consumed 18% more antibiotics per capita than Denmark during 2003 and more than other countries with established programs to track and control consumption.[1,3] Moreover, BC consumes proportionately far more in the way of newer and more expensive classes of antibiotics (six times the consumption of fluoroquinolones when compared with Denmark). Figure 1 illustrates the 55% growth in fluoroquinolone and 155% growth in new macrolide (azithromycin and clarithromycin) consumption in BC between 1996 and 2003.

Rates of resistance to fluoroquinolones are increasing among a number of bacterial species in BC (Figure 2) and among pneumococci nationally.[4] Macrolide resistance in pneumococci is becoming a concern in Canada and may be selected for by broad use of longer-acting newer macrolides.[4-6]

What can we do about it?

European jurisdictions and the province of Alberta have put together concerted efforts to reduce overuse of antimicrobials. These programs involve:

• Education for patients and the public explaining that certain infections do not require antibiotics.
• Reinforcement of basic infection control practices in the community such as hand washing.
• Reinforcement among physicians that many classes of infection do not require antibiotics to resolve and that first line (e.g., simple beta-lactam) antibiotics are an appropriate first step in managing many community-acquired infections.
• Incentives for physicians in the form of continuing education credits for participating in educationally focused audits of prescribing practices for antibiotics.

In the coming months, it will be important that we BC physicians contribute our ideas and energy to strategies that reduce overuse of antibiotics, especially of newer classes. The problem can now be identified, measured, and tracked so that it is possible to determine if our efforts are working. In the near future, we will either manage to arrest the emergence of resistant organisms or be forced to cope with fewer options in treating infectious diseases. As physicians in this area, we may well wish to pay heed to the old Buddhist tenet that, “We create our own reality.”

—David M. Patrick, MD
—Fawziah Marra, PharmD
—Joan Tomblin, MD
—Mei Chong, MSc
—Lily Lin
—Aleina Tweed, MSc

References

1. Patrick DM, Marra F, Hutchinson J, et al. Per capita antibiotic consumption: How does a North American jurisdiction compare with Europe? Clin Infect Dis. 2004:39:11-17. PubMed Abstract 
2. Hutchinson JM, Patrick DM, Marra F. Measurement of antibiotic consumption: A practical guide to the use of the Anatomical Therapeutic Chemical classification and Defined Daily Dose system methodology in Canada. Can J Inf Dis and Med Mic 2004:15:29-35.  
3. DANMAP 2003—Use of antimicrobial agents and occurrence of antimicrobial resistance in bacteria from food animals, foods, and humans in Denmark. ISSN 1600-2032. Available at www.dfvf.dk/Default.asp?ID=8590 (accessed 5 October 2004). 
4. Canadian Bacterial Surveillance Network, 15 April 2004. Available at http://microbiology.mtsinai.on.ca/data/sp/sp_2003.shtml#figure5 (accessed 1 September 2004). 
5. Davidson RJ, Chan CCK, Doern G, et al. Macrolide-resistant Streptococcus pneumoniae in Canada: Correlation with azithromycin use. 13th European Congress of Clinical Microbiology and Infectious Diseases, Glasgow, UK, 10–13 May 2003. Abstract #P1031. 
6. Pong-Porter S, Green K, McGeer A, et al. On behalf of the Canadian Bacterial Diseases Network. Antibiotic resistance trends in Canadian strains of Streptococcus pneumoniae. 13th European Congress of Clinical Microbiology and Infectious Diseases, Glasgow, UK, 10-13 May 2003. Abstract #P1447.