SARS-CoV-2 transmission risk for common group activities and settings: a living scoping review.

BACKGROUND: While the modes of transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are well studied, the risk of transmission in various group settings or activities is less clear. This living scoping review aims to summarize the risk factors of coronavirus disease 2019 (COVID-19) spread in common group activities (e.g. social gatherings) or settings (e.g. schools, hospitals, shared workplaces) to understand the drivers of transmission and to inform a risk assessment profile tool for use of rapid antigen detection tests. METHODS: We systematically searched electronic databases, MEDLINE and Embase, from January 2019 until February 2022. We included studies that evaluated the risk of SARS-CoV-2 transmission in activities and settings, deemed strategically important to government departments in Ireland, provided by the Department of Health (Ireland) Expert Advisory Group on Rapid Testing. RESULTS: After screening 14 052 records, data from 139 studies were narratively synthesized. The risk was consistently reported as 'high' for large social events (e.g. weddings) and indoor sports, working in healthcare settings and shared workplaces, working/living in residential settings and travelling via public transportation. Most studies were from healthcare settings, with common risk factors including close contact with COVID-19 cases, working in high-risk departments and inappropriate use of personal protective equipment. For other settings and activities, lack of infection prevention and control practices reportedly contributed to infection transmission. CONCLUSION: The heterogeneity across studies and lack of direct information on dominant variants, preventive measures, vaccination coverage necessitates further research on transmission risk within group activities to inform infection prevention and control measures.

Performance of different rapid antigen testing strategies for SARS-CoV-2: A living rapid review.

BACKGROUND: Rapid antigen detection tests (RADTs) for SARS-CoV-2 testing offer several advantages over molecular tests, but there is little evidence supporting an ideal testing algorithm. We aimed to examine the diagnostic test accuracy (DTA) and the effectiveness of different RADT SARS-CoV-2 testing strategies. METHODS: Following PRISMA DTA guidance, we carried out a living rapid review and meta-analysis. Searches were conducted in Ovid MEDLINE® ALL, Embase and Cochrane CENTRAL electronic databases until February 2022. Results were visualized using forest plots and included in random-effects univariate meta-analyses, where eligible. RESULTS: After screening 8010 records, 18 studies were included. Only one study provided data on incidence outcomes. Seventeen studies were DTA reports with direct comparisons of RADT strategies, using RT-PCR as the reference standard. Testing settings varied, corresponding to original SARS-CoV-2 or early variants. Strategies included differences in serial testing, the individual collecting swabs and swab sample locations. Overall, specificity remained high (>98%) across strategies. Although results were heterogeneous, the sensitivity for healthcare worker-collected samples was greater than for self-collected samples. Nasal samples had comparable sensitivity when compared to paired RADTs with nasopharyngeal samples, but sensitivity was much lower for saliva samples. The limited evidence for serial testing suggested higher sensitivity if RADTs were administered every 3 days compared to less frequent testing. CONCLUSIONS: Additional high-quality research is needed to confirm our findings; all studies were judged to be at risk of bias, with significant heterogeneity in sensitivity estimates. Evaluations of testing algorithms in real-world settings are recommended, especially for transmission and incidence outcomes.

Development of a risk assessment profile tool to determine appropriate use of SARS-CoV-2 rapid antigen detection tests for different activities and events in Ireland, since October 2021.

We describe the development of a risk assessment profile tool that incorporates data from multiple domains to help determine activities and events where rapid antigen detection tests (Ag-RDT) could be used to screen asymptomatic individuals to identify infectious cases as an additional mitigation measure to reduce transmission of SARS-CoV-2. The tool aims to stratify, in real time, the overall risk of SARS-CoV-2 transmission associated with common activities and events, and this can be matched to an appropriate Ag-RDT testing protocol.

Rapid diagnosis of seasonal Influenza virus and cohorting of hospitalised patients on a 'flu ward'. A prospective analysis of outcomes.

BACKGROUND: The influenza season of 2017/2018 was burdensome in comparison to previous years. In patient management of seasonal influenza patients is poorly described. AIM: To assess the impact of managing influenza patients on a dedicated influenza ward on antimicrobial use and duration, and length of stay (LOS). METHODS: A prospective cohort study from Jan 1st to Feb 28th 2018. Patients diagnosed with influenza in the Emergency Department (ED) were cohorted under infectious disease (ID) or a general internal medicine (GIM) firms on a 35 bed influenza ward. At times of maximum capacity some patients were managed on other wards by other firms 'non flu ward'. FINDINGS: 91 patients were admitted to the influenza ward from ED (64 ID, 27 GIM), 38 had influenza A. Patients managed by ID were more likely to be switched to oral antibiotics sooner median 3 vs 5 days p=.049. Antibiotic duration was shorter for patients managed by the ID firm median 7 vs 9 days p=.016. LOS was shorter for patients managed by the ID firm on the flu ward vs 'non flu ward', median 5 vs 9 days p=.007. No significant difference was seen between ID and GIM LOS on the flu ward, median 5 vs 7 days p=0.30. CONCLUSION: Influenza patients managed by an infectious disease service on an influenza ward had reduced length of intravenous (IV) and total antimicrobial use compared to a GIM service and had reduced LOS compared to the standard of care, 'non flu ward' influenza patients.

Molecular epidemiology of circulating measles virus in Ireland 2002-2007.

The molecular characterization of measles virus (MeV) is a valuable epidemiological tool to monitor virus transmission and to discriminate between imported and endemic infection. There has been significant immigration into Ireland in recent years and many individuals originate from regions of high measles incidence. Ireland has had a number of outbreaks of MeV which appear attributable to sub-optimal vaccine uptake and possibly imported strains as new genotypes have been identified in recent years. To ascertain any significant changes in circulating measles genotypes we investigated 65 confirmed measles cases between the years 2002 and 2007. The laboratory diagnosis of measles was confirmed by detection of measles-specific IgM in oral fluid in conjunction with a real-time polymerase chain reaction assay targeting the MeV hemagglutinin gene. Phylogenetic analysis based on the 3' hypervariable region of the nucleoprotein gene was performed and three genotypes, all within measles clade D, were found to be circulating during this time period. In 2002 and 2003, genotype D8 (n = 2) was observed whereas genotype D7 was dominant in 2003 (n = 31). A distinct change in the circulating MeV genotype and increased genetic diversity was observed between 2004 and 2007. All cases were within genotype D4 (n = 32) but were phylogenetically distinct from each other. These data provide important epidemiologic baseline information on MeV in Ireland and facilitates detailed examination of measles transmission.