Impact of participation in a surgical site infection surveillance network: results from a large international cohort study

J Hosp Infect. 2019 Jul;102(3):267-276. doi: 10.1016/j.jhin.2018.12.003. Epub 2018 Dec 7.


Background: Surveillance of surgical site infections (SSIs) is a core component of effective infection control practices, though its impact has not been quantified on a large scale.

Aim: To determine the time-trend of SSI rates in surveillance networks.

Methods: SSI surveillance networks provided procedure-specific data on numbers of SSIs and operations, stratified by hospitals' year of participation in the surveillance, to capture length of participation as an exposure. Pooled and procedure-specific random-effects Poisson regression was performed to obtain yearly rate ratios (RRs) with 95% confidence intervals (CIs), and including surveillance network as random intercept.

Findings: Of 36 invited networks, 17 networks from 15 high-income countries across Asia, Australia and Europe participated in the study. Aggregated data on 17 surgical procedures (cardiovascular, digestive, gynaecological-obstetrical, neurosurgical, and orthopaedic) were collected, resulting in data concerning 5,831,737 operations and 113,166 SSIs. There was a significant decrease in overall SSI rates over surveillance time, resulting in a 35% reduction at the ninth (final) included year of surveillance (RR: 0.65; 95% CI: 0.63-0.67). There were large variations across procedure-specific trends, but strong consistent decreases were observed for colorectal surgery, herniorrhaphy, caesarean section, hip prosthesis, and knee prosthesis.

Conclusion: In this large, international cohort study, pooled SSI rates were associated with a stable and sustainable decrease after joining an SSI surveillance network; a causal relationship is possible, although unproven. There was heterogeneity in procedure-specific trends. These findings support the pivotal role of surveillance in reducing infection rates and call for widespread implementation of hospital-based SSI surveillance in high-income countries.

Keywords: Epidemiology; Healthcare-associated infection; Infection control; Surgical site infection; Surveillance; Surveillance networks.

MeSH terms

  • Asia / epidemiology
  • Australia / epidemiology
  • Epidemiological Monitoring*
  • Europe / epidemiology
  • Humans
  • Incidence
  • Infection Control / methods*
  • International Cooperation*
  • Retrospective Studies
  • Surgical Wound Infection / epidemiology*
  • Surgical Wound Infection / prevention & control*