ANTIMICROBIAL USE AND RESISTANCE SURVEILLANCE PILOT PROJECT LESSONS FROM THE DURBAN SITE

1
ANTIMICROBIAL USE AND RESISTANCE SURVEILLANCE
PILOT PROJECT LESSONS FROM THE DURBAN SITE

• Gray AL, Essack SY, Deedat F, Pillay T, van
  Maasdyk J, Holloway K, Sorensen TL, Sturm
  AWDept. Pharmacology and Dept. Medical
  Microbiology, Nelson R Mandela School of
  Medicine, School of Pharmaceutical Sciences,
  Univ. KwaZulu-Natal, Durban, South Africa,
  WHO/EDM, Geneva

2
Abstract

•  Problem Statement The World Health
  Organizations global strategy for containing
  antimicrobial resistance recommends the
  development of methodologies that will enable
  developing countries to identify and track
  resistance trends in specific infections and
  geographical locations. Standard methods for such
  surveillance systems do not exist for
  resource-constrained settings.
• Objectives To investigate the association
  between antibiotic use and resistance over time
  in respiratory tract infections in the Inner West
  metropolitan area of Durban.
• Design Retrospective, time series analysis of
  antimicrobial use data and antimicrobial
  resistance of selected isolates.
• Setting and population 7 randomly selected
  private pharmacies, 7 convenience sampled private
  dispensing practitioners and 7 randomly selected
  state-operated nurse-managed primary health care
  clinics.
• Methods Antimicrobial use data were obtained
  from prescription records at sites representing a
  broad spectrum of socio-economic conditions and
  prescriber types. Sputum specimens were obtained
  from consenting patients presenting with
  self-reported cough with or without fever at 4
  sites in the selected geographical locale.
  Cultures positive for Streptococcus pneumoniae,
  Haemophilus influenzae and Moraxella catarrhalis
  were subjected to MIC determinations against
  ampicillin, erythromycin, chloramphenicol,
  cotrimoxazole and ciprofloxacin by means of agar
  dilution. NCCLS breakpoints were applied to
  determine resistance.
• Outcome measures Percentage of patients seen (or
  prescriptions dispensed) in which an
  antimicrobial was prescribed antimicrobial usage
  in Defined Daily Doses per 100 patients seen
  percentage susceptibility of selected isolates.
• Results High usage of older antimicrobial agents
  was seen in public sector clinics and lower usage
  of a wide range of agents, including newer
  broad-spectrum antimicrobials, in the private
  sector. Percentage resistance of selected
  isolates by time series per quarter showed an
  decreasing level of resistance amongst
  pneumococci to ampicillin and erythromycin, but
  continuously total resistance to cotrimoxazole.
  Increasing trends in resistance to ampicillin
  were shown amongst H influenzae, but decreasing
  trends in resistance to cotrimoxazole.
• Conclusions Although no direct relationship
  between resistance levels and antimicrobial usage
  could be shown, the feasibility of establishing a
  system to generate data of this sort was
  demonstrated. Further analysis over time is
  planned.
• Study funded by World Health Organization.

3
Background

• In September 2001 the WHO released the Global
  Strategy for Containment of Antimicrobial
  Resistance (WHO/CDS/CSR/DRS/2001.2)
• This document identified 67 interventions
  targeted at different groups
• It also identified the need for linked
  surveillance of antimicrobial resistance and use,
  in order to assess these interventions
• Not clear how to achieve this in
  resource-constrained setting

4
Objectives

• To investigate the association between antibiotic
  use and resistance over time in respiratory tract
  infections in the Inner West metropolitan area of
  Durban, South Africa

5
Methods resistance

• Sputum specimens
• consenting patients with self-reported cough,
  with or without fever
• 4 convenience sampled sites
• Public and private sector
• Standard laboratory work-up
• Selective cultures for
• Streptococcus pneumoniae
• Haemophilus influenzae
• Moraxella catarrhalis
• MIC determinations
• ampicillin, erythromycin, chloramphenicol,
  cotrimoxazole and ciprofloxacin
• agar dilution
• standard NCCLS breakpoints

6
Methods antimicrobial use

• Retrospective prescription audit (2 weeks Rx
  per month)
• 7 randomly selected private pharmacies
  (stratified by socio-economic status of area
  data from original prescriptions)
• 7 convenience sampled private dispensing
  practitioners (stratified by socio-economic area
  data from clinical records)
• 7 randomly selected primary health care clinics
  (stratified by size data from daily clinic
  registers)
• Data analysis
• patients seen (or prescriptions dispensed) in
  which an antimicrobial was prescribed
• antimicrobial usage in Defined Daily Doses per
  100 patients seen (clinics and doctors) or
  prescriptions dispensed (pharmacies)
• susceptibility of selected isolates - all by
  time series

7
S. pneumoniae resistance(ciprofloxacin not
tested)
8
H. Influenzae resistance(no resistance to
erythromycin or ciprofloxacin)
9
Antimicobial use overall
10
Antimicrobial use - cotrimoxazole
Winter
11
Antimicrobial use - quinolones
Winter
12
Antimicrobial use all antimicrobials
Winter
13
Conclusions and Acknowledgements

• Although no direct relationship between
  resistance levels and antimicrobial usage could
  be shown, the feasibility of establishing a
  system to generate data of this sort was
  demonstrated
• Given the differences in antimicrobial use
  patterns in different settings, interventions to
  contain the development of resistance will have
  to be carefully tailored for each setting
• Thanks to WHO/EDM for funding this pilot
  project, the fieldworkers and laboratory staff,
  the staff at the facilities, for allowing us
  access to their patients and their data, the
  patients who provided sputum samples