O040: The effect of improved hand hygiene compliance on nosocomial transmission of Staphylococcus aureus

Objectives

The objective of this prospective interventional study was to observe the effect of improved hand hygiene compliance(HHC) on nosocomial transmission of S.aureus between patients.

Methods

The study was conducted between Oct 2011 and Dec 2012 in the oncology ward of a Dutch Teaching Hospital and contained multiple consecutive interventions: [I]increase number of hand alcohol dispensers; [II]education on HH; [III]replacing standard hand alcohol and soap dispensers by new automated dispensers, no feedback was given; [IV]personal feedback of HHC.

HHC was manually monitored according to the WHO method, twice a week during the whole study period. All patients were cultured weekly to detect nasal carriage of S.aureus. Isolates collected in period [II] and [IV] were typed using Amplification Fragment Length Polymorphism (AFLP). The ratio between secondary and primary cases, Transmission Index (TI), was calculated.

Results

The HHC improved significantly from 31.5%(92/302;CI 25.3-36.0) in period [II] to 52.9%(139/263;CI 46.6-59.0) in period [IV](p<0.001).

In period [II] 266 patients were hospitalized on the days of culture; 246 nasal swabs(92.5%) were collected from 151 unique patients. In total 42/151 patients(27.5%) were S.aureus carriers. AFLP revealed 6 unrelated isolates and 13 clusters (2-14 isolates,median 3). Number of primary cases(PC) was 19. Transmission of S.aureus from a PC to other patients occurred in 10 out of 19(52.6%) PC, resulting in 22 secondary cases(SC). TI of 1.2(22/19).

In period [IV] 314 patients were hospitalized on the days of culture; 268 nasal swabs(85.4%) were collected from 134 unique patients. In total 45/134 patients(33.6%) were S.aureus carriers. AFLP revealed 16 unrelated isolates and 9 clusters (2-7 isolates,median 3). Number of PC was 25. Transmission of S.aureus from a PC to other patients occurred in 9 of 25(36.0%) PC, resulting in 17 SC. TI of 0.7(17/25).

The ratio of unique versus clustered strains was significantly higher in period IV(p=0.028).

Conclusion

An improvement of HHC from 31.5% to 52.9%(RR:1.68) was associated with a 32%reduction of the TI. This study shows that improvement of HHC using automatic dispensers with personal feedback reduces the transmission of S.aureus in the hospital substantially.

Disclosure of interest

None declared.