ABSTRACT
The outbreak of the COVID-19 pandemic in late 2019 has so far caused more than 6 million deaths worldwide according to WHO. Currently, there is only one FDA-approved novel antiviral drug therapy (Paxlovid, Pfizer) for treatment of critically ill patients from COVID-19 infection. However, there is a need for a great diversity of antiviral therapies because of the constant mutations of the virus and the possibility of other similar viruses causing similar symptoms in patients. By utilizing natural products from medicinal plants, it is possible to provide a drug, or drug leads for a future novel antiviral therapy. Currently, we are testing isolated and characterized natural products (some novel and some already elucidated) from water lily (Nuphar lutea) and eagle fern (Pteridium aquilinum) on the SARS-CoV-2 virus where we are working on developing a good pipeline to test these compounds in vitro. So far, we have tested the effect of the compounds on inhibition of cell entry using a pseudovirus system and HEK293-FT cells transiently transfected with SARS-CoV-2 receptors ACE-2 and TMPRSS2. Some of the compounds showed a slightly inhibitory effect. Next steps will be to establish a cell line with stable expression of ACE-2 and TMPRSS2 and confirm the results in cells with endogenous expression of these receptors. We will proceed working with different variants of the hospital isolates of the virus within the next months, where we will further analyse the potential effect of these compounds on viral replication. The goal is to determine and understand the mechanism of inhibitory action of the natural products on the virus. In conclusion, we are at an early stage of researching the abundant possibilities of antiviral effects of these natural products on SARS-CoV-2.
ABSTRACT
INTRODUCTION: Fast and accurate detection of SARS-CoV-2 is essential in limiting the COVID-19 pandemic. Rapid antigen (AG) tests provide results within minutes;however, their accuracy has been questioned. The study aims to determine the accuracy and cost of the STANDARD Q COVID-19 AG test compared with RT-PCR. METHODS: Individuals 18 years or older with an appointment for a RT-PCR test on 26-31 December 2020 at a public test centre in Copenhagen, Denmark were invited to participate. An oropharyngeal swab was collected for RT-PCR analysis, followed by a nasopharyngeal swab examined by the AG test (SD Biosensor). The diagnostic accuracy of the AG test was calculated with RT-PCR as reference. Costs were evaluated for both tests. RESULTS: A total of 4,811 paired conclusive test results were collected (median age: 45 years, female: 53%). The RT-PCR test revealed 221 (4.6%) positive tests. The overall sensitivity and specificity of the AG test were 69.7% and 99.5%, respectively. Viral cycle threshold values were significantly higher in individuals with false negative AG tests than in individuals who were true positives. The RT-PCR test and AG test costs were 67.0 DKK (10.8 USD) and 35.0 DKK (5.7 USD), respectively, per positive case detected at 100,000 daily tests. CONCLUSIONS: The AG test enables mass testing and provides immediate results, which is important in SARS-CoV-2 screening. The AG test is a good and relevant supplement to RT-PCR testing in public SARS-CoV-2 screenings. FUNDING: This project received no external funding. Copenhagen Medical A/S delivering the rapid AG tests and provided test personnel but were not otherwise involved. TRIAL REGISTRATION: Clinicaltrials.org: NCT04716088.
ABSTRACT
INTRODUCTION: The reference test to evaluate patients with suspected respiratory virus infection is a real-time reverse transcription-polymerase chain reaction (RT-PCR) from a nasopharyngeal swab (NPS). However, other specimen collection methods such as an oropharyngeal swab (OPS) or saliva specimen are also used for SARS-CoV-2 testing during the ongoing COVID-19 pandemic. However, it remains unclear if rates of SARS-CoV-2 detection differ between sampling methods. This study will compare the rates of SARS-CoV-2 detection by saliva, OPS, and NPS sampling in a public setting. METHODS: Individuals referred for outpatient SARS-CoV-2 testing will be invited to participate in a prospective clinical study. They will have saliva, OPS and NPS specimens collected that will be analysed separately for SARS-CoV-2 RNA by RT-PCR. The rate of SARS-CoV-2 detection in saliva, OPS and NPS will be compared using a logistic regression mixed-effect model analysis. A sample of 19,110 participants is required at an expected 1.5% test-positive rate in order to detect a 25.6% difference. The total sample size will be adjusted as the test-positive rate changes. CONCLUSIONS: This study will provide evidence for the optimal site of specimen collection to detect SARS-CoV-2. The results may help guide the health authorities. FUNDING: This is an investigator-initiated trial based on an unrestricted grant from the Novo Nordisk Foundation and the Aage og Johanne Louis-Hansens Fond. The foundations have had no say in the decisions on study design or reporting. TRIAL REGISTRATION: ClinicalTrials.gov (ID: NCT04715607).