Eurosurveillance - Volume 20, Issue 8, 26 February 2015

Preliminary results for the 2014/15 season indicate low to null effect of vaccination against influenza A(H3N2)-related disease. As of week 5 2015, there have been 1,136 hospital admissions, 210 were due to influenza and 98% of subtype A strains were H3. Adjusted influenza vaccine effectiveness was 33% (range: 6-53%) overall and 40% (range: 13% to 59%) in those 65 years and older. Vaccination reduced by 44% (28-68%) the probability of admission with influenza. .

To evaluate seasonal trivalent inactivated influenza vaccine effectiveness (VE) in Scotland, we performed a Scotland-wide linkage of patient-level primary care, hospital and virological swab data from 3,323 swabs (pooling data over nine influenza seasons: 2000/01 to 2008/09). We estimated the VE for reducing real-time RT-PCR-confirmed influenza using a test-negative study design. Vaccination was associated with a 57% (95% confidence interval (CI): 31-73) reduction in the risk of PCR-confirmed influenza. VE was 60% (95% CI: 22-79) for patients younger than 65 years and clinically at risk of serious complications from influenza, and 19% (95% CI: ?104 to 68) for any individual 65 years and older. Vaccination was associated with substantial, sustained reductions in laboratory-confirmed influenza in the general population and younger patients in clinical at-risk groups. .

We present a pilot validation study performed on 10 European Union (EU) Member States, of a point prevalence survey (PPS) of healthcare-associated infections (HAIs) and antimicrobial use in Europe in 2011 involving 29 EU/European Economic Area (EEA) countries and Croatia. A total of 20 acute hospitals and 1,950 patient records were included in the pilot study, which consisted of validation and inter-rater reliability (IRR) testing using an in-hospital observation approach. In the validation, a sensitivity of 83% (95% confidence interval (CI): 79-87%) and a specificity of 98% (95% CI: 98-99%) were found for HAIs. The level of agreement between the primary PPS and validation results were very good for HAIs overall (Cohen's ?appa (?): 0.81) and across all the types of HAIs (range: 0.83 for bloodstream infections to 1.00 for lower respiratory tract infections). Antimicrobial use had a sensitivity of 94% (95% CI: 93-95%) and specificity of 97% (95% CI: 96-98%) with a very good level of agreement (?: 0.91). Agreement on other demographic items ranged from moderate to very good (?: 0.57-0.95): age (?: 0.95), sex (?: 0.93), specialty of physician (?: 0.87) and McCabe score (?: 0.57). IRR showed a very good level of agreement (?: 0.92) for both the presence of HAIs and antimicrobial use. This pilot study suggested valid and reliable reporting of HAIs and antimicrobial use in the PPS dataset. The lower level of sensitivity with respect to reporting of HAIs reinforces the importance of training data collectors and including validation studies as part of a PPS in order for the burden of HAIs to be better estimated. .

Post-discharge surveillance (PDS) for surgical site infections (SSIs) normally lasts 30 days, or one year after implant surgery, causing delayed feedback to healthcare professionals. We investigated the effect of shortened PDS durations on SSI incidence to determine whether shorter PDS durations are justified. We also studied the impact of two national PDS methods (those mandatory since 2009 ('mandatory') and other methods acceptable before 2009 ('other')) on SSI incidence. From Dutch surveillance (PREZIES) data (1999-2008), four implant-free surgeries (breast amputation, Caesarean section, laparoscopic cholecystectomy and colectomy) and two implant surgeries (knee replacement and total hip replacement) were selected . We studied the impact of PDS duration and method on SSI incidences by survival and Cox regression analyses. We included 105,607 operations. Shortened PDS duration for implant surgery from one year to 90 days resulted in 6-14% of all SSIs being missed. For implant-free procedures, PDS reduction from 30 to 21 days caused similar levels of missed SSIs. In contrast, up to 62% of SSIs (for cholecystectomy) were missed if other instead of mandatory PDS methods were used. Inferior methods of PDS, rather than shortened PDS durations, may lead to greater underestimation of SSI incidence. Our data validate international recommendations to limit the maximum PDS duration (for implant surgeries) to 90 days for surveillance purposes, as this provides robust insight into trends. .