Performance of hospital-based contact tracing for COVID-19 during Australia's second wave.

BACKGROUND: Hospital-based contact tracing aims to limit spread of COVID-19 within healthcare facilities. In large outbreaks, this can stretch resources and workforce due to quarantine of uninfected staff. We analysed the performance of a manual contact tracing system for healthcare workers (HCW) at a multi-site healthcare facility in Melbourne, Australia, from June-September 2020, during an epidemic of COVID-19. METHODS: All HCW close contacts were quarantined for 14 days, and tested around day 11, if not already diagnosed with COVID-19. We examined the prevalence and timing of symptoms in cases detected during quarantine, described this group as proportions of all close contacts and of all cases, and used logistic regression to assess factors associated with infection. RESULTS: COVID-19 was diagnosed during quarantine in 52 furloughed HCWs, from 483 quarantine episodes (11%), accounting for 19% (52/270) of total HCW cases. In 361 exposures to a clear index case, odds of infection were higher after contact with an infectious patient compared to an infectious HCW (aOR: 4.69, 95% CI: 1.98-12.14). Contact with cases outside the workplace increased odds of infection compared to workplace contact only (aOR: 7.70, 95% CI: 2.63-23.05). We estimated 30%, 78% and 95% of symptomatic cases would develop symptoms by days 3, 7, and 11 of quarantine, respectively. CONCLUSION: In our setting, hospital-based contact tracing detected and contained a significant proportion of HCW cases, without excessive quarantine of uninfected staff. Effectiveness of contact tracing is determined by a range of dynamic factors, so system performance should be monitored in real-time.

Clinical presentation and management of COVID-19.

The rapid spread of severe acute respiratory syndrome coronavirus 2 led to the declaration of a global pandemic within 3 months of its emergence. The majority of patients presenting with coronavirus disease 2019 (COVID-19) experience a mild illness that can usually be managed in the community. Patients require careful monitoring and early referral to hospital if any signs of clinical deterioration occur. Increased age and the presence of comorbidities are associated with more severe disease and poorer outcomes. Treatment for COVID-19 is currently predominantly supportive care, focused on appropriate management of respiratory dysfunction. Clinical evidence is emerging for some specific therapies (including antiviral and immune-modulating agents). Investigational therapies for COVID-19 should be used in the context of approved randomised controlled trials. Australian clinicians need to be able to recognise, diagnose, manage and appropriately refer patients affected by COVID-19, with thousands of cases likely to present over the coming years.

Pandemic printing: a novel 3D-printed swab for detecting SARS-CoV-2.

OBJECTIVES: To design and evaluate 3D-printed nasal swabs for collection of samples for SARS-CoV-2 testing. DESIGN: An iterative design process was employed. Laboratory evaluation included in vitro assessment of mock nasopharyngeal samples spiked with two different concentrations of gamma-irradiated SARS-CoV-2. A prospective clinical study compared SARS-CoV-2 and human cellular material recovery by 3D-printed swabs and standard nasopharyngeal swabs. SETTING, PARTICIPANTS: Royal Melbourne Hospital, May 2020. Participants in the clinical evaluation were 50 hospital staff members attending a COVID-19 screening clinic and two inpatients with laboratory-confirmed COVID-19. INTERVENTION: In the clinical evaluation, a flocked nasopharyngeal swab sample was collected with the Copan ESwab and a mid-nasal sample from the other nostril was collected with the 3D-printed swab. RESULTS: In the laboratory evaluation, qualitative agreement with regard to SARS-CoV-2 detection in mock samples collected with 3D-printed swabs and two standard swabs was complete. In the clinical evaluation, qualitative agreement with regard to RNase P detection (a surrogate measure of adequate collection of human cellular material) in samples collected from 50 hospital staff members with standard and 3D-printed swabs was complete. Qualitative agreement with regard to SARS-CoV-2 detection in three pairs of 3D-printed mid-nasal and standard swab samples from two inpatients with laboratory-confirmed SARS-CoV-2 was also complete. CONCLUSIONS: Using 3D-printed swabs to collect nasal samples for SARS-CoV-2 testing is feasible, acceptable to patients and health carers, and convenient.