ABSTRACT
BACKGROUND: Little is known about how asymptomatic testing as a method to control transmission of COVID-19 can be implemented, and the prevalence of asymptomatic infection within university populations. The objective of this study was to investigate how to effectively set-up and implement a COVID-19 testing programme using novel reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) technology and to quantify the scale of asymptomatic infection on a university campus. METHODS: An observational study to describe the set-up and implementation of a novel COVID-19 testing programme on a UK university campus between September and December 2020. RT-LAMP testing was used to identify asymptomatic cases. RESULTS: A total of 1,673 tests were performed using RT-LAMP during the study period, of which 9 were positive for COVID-19, giving an overall positivity rate of 0.54%, equivalent to a rate in the tested population of 538 cases per 100,000 over the duration of testing. All positive tests were found to be positive on RT-PCR testing, giving a false positive rate of 0%. CONCLUSIONS: This study shows that it is possible to rapidly setup a universal university testing programme for COVID-19 in collaboration with local healthcare providers using RT-LAMP testing. Positive results were comparable to those in the local population, though with a different peak of infection. Further research to inform the design of the testing programme includes focus groups of those who underwent testing and further interrogation of the demographics of those opting to be tested to identify potential access problems or inequalities.
Subject(s)
COVID-19 Testing , COVID-19 , Humans , COVID-19/diagnosis , COVID-19/epidemiology , SARS-CoV-2 , Asymptomatic Infections , Sensitivity and Specificity , Molecular Diagnostic Techniques/methods , United Kingdom/epidemiologyABSTRACT
PURPOSE: To demonstrate the diagnostic performance of rapid SARS-CoV-2 RT-LAMP assays, comparing the performance of genomic versus sub-genomic sequence target with subsequent application in an asymptomatic screening population. METHODS: RT-LAMP diagnostic specificity (DSe) and sensitivity (DSe) was determined using 114 RT-PCR clinically positive and 88 RT-PCR clinically negative swab samples processed through the diagnostic RT-PCR service within the University Hospitals of Leicester NHS Trust. A swab-based RT-LAMP SARS-CoV-2 screening programme was subsequently made available to all staff and students at the University of Leicester (Autumn 2020), implemented to ISO 15189:2012 standards using NHS IT infrastructure and supported by University Hospital Leicester via confirmatory NHS diagnostic laboratory testing of RT-LAMP 'positive' samples. RESULTS: Validation samples reporting a Ct < 20 were detected at 100% DSe and DSp, reducing to 95% DSe (100% DSp) for all samples reporting a Ct < 30 (both genomic dual sub-genomic assays). Advisory screening identified nine positive cases in 1680 symptom free individuals (equivalent to 540 cases per 100,000) with results reported back to participants and feed into national statistics within 48 hours. CONCLUSION: This work demonstrates the utility of a rapid RT-LAMP assay for collapsing transmission of SARS-CoV-2 in an asymptomatic screening population.
Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/diagnosis , COVID-19/epidemiology , Humans , Molecular Diagnostic Techniques/methods , Nucleic Acid Amplification Techniques/methods , RNA, Viral/genetics , SARS-CoV-2/genetics , Sensitivity and SpecificityABSTRACT
Background Little is known about how asymptomatic testing as a method to control the transmission of COVID-19 can be successfully implemented, and the prevalence of asymptomatic infection within university populations. The aim of this study was to describe the methodology of implementing a novel asymptomatic mass testing programme, and to report the number of positive cases diagnosed during the study period. To our knowledge, this study is the first to report prevalence of asymptomatic COVID-19 infection within a UK university population using reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) as a molecular diagnostic tool. Methods An observational study was undertaken to describe the set-up and implementation of a novel COVID-19 testing programme on a UK university campus between Sept 28 and Dec 18, 2020. Students and staff members volunteered for testing throughout the term. The programme used RT-LAMP testing to identify asymptomatic cases within the population. Any positive cases received RT-PCR testing to confirm the result using the current gold-standard testing methodology. Findings 1673 tests were done using RT-LAMP during the study period, of which nine were positive for COVID-19. This gave an overall positivity rate of 0·54%, equivalent to a rate in the tested population of 538 cases per 100 000 over the duration of testing. All positive tests were also found to be positive on RT-PCR testing, giving a false positive rate of 0%. Uptake was affected by changes to delivery of university teaching, leading to lower attendance on campus throughout the term. Interpretation This study shows that it is possible to rapidly set up a universal university testing programme for COVID-19 in collaboration with local health-care providers using RT-LAMP testing, with full concordance between RT-LAMP testing and RT-PCR testing on positive RT-LAMP results. Positive results were similar to those in the local population, although with a different weekly peak of infection. Funding None.