P038: Efficacy of prevention measures against nosocomial influenza at a large university hospital

Introduction

At HUG, healthcare workers (HCW) are currently obliged to be vaccinated or wear masks in ward corridors and patient rooms during seasonal influenza (SI) epidemics. Since winter 2011-12, HCWs vaccinated against SI wear a badge with the text "I am vaccinated to protect you" and, since winter 2012-13, those who are not vaccinated wear a badge with the text "I wear a mask to protect you". Regular audits have allowed to quantify compliance with recommendations in parallel with active recording of influenza cases.

Methods

During the SI epidemic, an audit recorded HCWs with a badge and those with correct mask wear over 2 periods of 2 weeks each in Feb−March 2012 and 3 periods of 2 weeks each in Jan−March 2013. Compliance was assessed as follows: (number of HCWs wearing a colored badge + number of HCWs wearing a mask correctly)/number of HCWs observed = number of compliant HCWs/number of HCWs observed, expressed as a percentage. Suspected cases of SI were confirmed by positive realtime RT-PCR reaction. Cases were defined as nosocomial (NOSO) SI when symptoms occurred >72 h post-admission.

Results

Of 1390 HCWs observed in winter 2012, 469 wore a badge or mask (estimated compliance, 33.5%). In winter 2013, 2070/2937 observed HCWs were compliant (70.5%). We recorded 84 NOSO SI /152 SI (55.2%) and 96 NOSO SI /267 SI (35.9%) cases during 2011-12 and 2012-13, respectively. Compliance with recommendations in internal medicine averaged 68.6% in 2012 and 72.2% in 2013. The proportion of NOSO SI cases remained stable (30.3% and 21.6%, respectively). At the geriatric hospital, compliance progressed from 58.6% to 72.2%, while the proportion of NOSO SI cases decreased from 84.9% to 63.3%, respectively. These measures prevented an estimated number of 115 NOSO SI cases at HUG in 2012-13, together with a reduced number of deaths among SI patients.

Conclusion

Mandatory badge wear, continuous SI epidemic surveillance and availability of compliance rates with recommendations decrease the risk of NOSO SI and improve patient safety.

Disclosure of interest

None declared