Quality of molecular detection of vancomycin resistance in enterococci: results of 6 consecutive years of Quality Control for Molecular Diagnostics (QCMD) external quality assessment.

The quality of PCR to detect vancomycin-resistant enterococci (VRE) was evaluated by analysing their performance in six consecutive external quality assessment (EQA) schemes, organized annually since 2013 by Quality Control for Molecular Diagnostics. VRE EQA panels consisted of 12-14 heat-inactivated samples. Sensitivity was tested with vanA-positive Enterococcus faecium (E. faecium), vanB-positive E. faecium, E. faecalis or E. gallinarum or vanC-positive E. gallinarum in different concentrations. Vancomycin-susceptible enterococci, Staphylococcus aureus or sample matrix was used to study the specificity. Participants were asked to report the VRE resistance status of each sample. The detection rate of vanA-positive samples was already 95% in the 2013 EQA panel (range 94-97%) and remained stable over the years. The 2013 detection rate of vanB-positive samples was 82% but increased significantly by more than 10% in subsequent years (96% in 2014, 95% in 2015, 92% in 2016 and 93% in 2017/2018, p < 0.05). The vanC detection rate by the limited number of assays specifically targeting this gene was lower compared to vanA/B (range 55-89%). The number of false positives in the true-negative sample (8% in 2013 to 1.4% in 2018) as well as the van-gene-negative bacterial samples (4% in 2013 to 0% in 2018) declined over the years. In the six years of VRE proficiency testing to date, the detection of vanA-positive strains was excellent and an increased sensitivity in vanB detection as well as an increase in specificity was observed. Commercial and in-house assays performed equally well.

Second external quality assessment of the molecular diagnostic of West Nile virus: are there improvements towards the detection of WNV?

BACKGROUND: WNV epidemics occur worldwide, new WNV isolates were isolated in southern-east Europe belonging to WNV lineage 2. A first international proficiency study on WNV indicted that some laboratories were not able to detect WNV lineage 2 virus genome by their PCR diagnostic assays. Therefore an actual External Quality Assessment with both virus lineages was performed to monitor the improvements in molecular diagnostics. OBJECTIVES: To asses the proficiency of laboratories to detect West Nile virus with molecular diagnostic tests. STUDY DESIGN: A test panel of different WNV isolates and virus dilutions was given to 26 laboratories to test the samples with their routine diagnostic methods. RESULTS: Twenty-one participating laboratories provided 28 data set results. WNV lineage 1 was detected with high overall efficiency of 92% (67.9-100%) but two different WNV lineage 2 strains were detected at lower rates (mean = 73%, 67.9-75%) by the different PCR assays. 93% of the laboratories were able to detect a WNV lineage 1 with a concentration of 1.2×10(4)copies/ml but the detection rate was decreased to 68% for 1.2×10(3)copies/ml. One laboratory generated false-positive result from the non-virus control samples and 29% of the datasets showed false-positive results for non-WNV flavivirus samples. CONCLUSIONS: The WNV EQA showed an improved proficiency of laboratories as compared to the first EQA. However, the data suggest that problems in the detection of both lineages were still present since the first proficiency test was performed in 2006. Further proceedings versus the detection of both lineages are needed particularly for in-house assays.

Legislation on smoking in enclosed public places in Scotland: how will we evaluate the impact?

BACKGROUND: From 26 March 2006, smoking will be prohibited in wholly and substantially enclosed public places in Scotland, and it will be an offence to permit smoking or to smoke in no-smoking premises. We anticipate that implementation of the smoke-free legislation will result in significant health gains associated with reductions in exposure to both environmental tobacco smoke (ETS) and personal tobacco consumption as well as other social and economic impacts. METHODS: Health Scotland in conjunction with the Information Services Division (ISD) Scotland and the Scottish Executive have developed a comprehensive evaluation strategy to assess the expected short-term, intermediate and long-term outcomes. Using routine health, behavioural and economic data and commissioned research, we will assess the impact of the smoke-free legislation in eight key outcome areas--knowledge and attitudes, ETS exposure, compliance, culture, smoking prevalence and tobacco consumption, tobacco-related morbidity and mortality, economic impacts on the hospitality sector and health inequalities. CONCLUSION: The findings from this evaluation will make a significant contribution to the international understanding of the health effects of exposure to ETS and the broader social, cultural and economic impacts of smoke-free legislation.