Reverse-Transcription Loop-Mediated Isothermal Amplification Has High Accuracy for Detecting Severe Acute Respiratory Syndrome Coronavirus 2 in Saliva and Nasopharyngeal/Oropharyngeal Swabs from Asymptomatic and Symptomatic Individuals.

Previous studies have described reverse-transcription loop-mediated isothermal amplification (RT-LAMP) for the rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in nasopharyngeal/oropharyngeal swab and saliva samples. This multisite clinical evaluation describes the validation of an improved sample preparation method for extraction-free RT-LAMP and reports clinical performance of four RT-LAMP assay formats for SARS-CoV-2 detection. Direct RT-LAMP was performed on 559 swabs and 86,760 saliva samples and RNA RT-LAMP on extracted RNA from 12,619 swabs and 12,521 saliva samples from asymptomatic and symptomatic individuals across health care and community settings. For direct RT-LAMP, overall diagnostic sensitivity (DSe) was 70.35% (95% CI, 63.48%-76.60%) on swabs and 84.62% (95% CI, 79.50%-88.88%) on saliva, with diagnostic specificity of 100% (95% CI, 98.98%-100.00%) on swabs and 100% (95% CI, 99.72%-100.00%) on saliva, compared with quantitative RT-PCR (RT-qPCR); analyzing samples with RT-qPCR ORF1ab CT values of ≤25 and ≤33, DSe values were 100% (95% CI, 96.34%-100%) and 77.78% (95% CI, 70.99%-83.62%) for swabs, and 99.01% (95% CI, 94.61%-99.97%) and 87.61% (95% CI, 82.69%-91.54%) for saliva, respectively. For RNA RT-LAMP, overall DSe and diagnostic specificity were 96.06% (95% CI, 92.88%-98.12%) and 99.99% (95% CI, 99.95%-100%) for swabs, and 80.65% (95% CI, 73.54%-86.54%) and 99.99% (95% CI, 99.95%-100%) for saliva, respectively. These findings demonstrate that RT-LAMP is applicable to a variety of use cases, including frequent, interval-based direct RT-LAMP of saliva from asymptomatic individuals who may otherwise be missed using symptomatic testing alone.

C-reactive protein-guided use of procalcitonin in COVID-19.

BACKGROUND: A low procalcitonin (PCT) concentration facilitates exclusion of bacterial co-infections in COVID-19, but high costs associated with PCT measurements preclude universal adoption. Changes in inflammatory markers, including C-reactive protein (CRP), can be concordant, and predicting low PCT concentrations may avoid costs of redundant tests and support more cost-effective deployment of this diagnostic biomarker. OBJECTIVES: To explore whether, in COVID-19, low PCT values could be predicted by the presence of low CRP concentrations. METHODS: Unselected cohort of 224 COVID-19 patients admitted to hospital that underwent daily PCT and CRP measurements as standard care. Both 0.25 ng/mL and 0.5 ng/mL were used as cut-offs for positive PCT test results. Geometric mean was used to define high and low CRP values at each timepoint assessed. RESULTS: Admission PCT was <0.25 ng/mL in 160/224 (71.4%), 0.25-0.5 ng/mL in 27 (12.0%) and >0.5 ng/mL in 37 (16.5%). Elevated PCT was associated with increased risk of death (P = 0.0004) and was more commonly associated with microbiological evidence of bacterial co-infection (P < 0.0001). For high CRP values, significant heterogeneity in PCT measurements was observed, with maximal positive predictive value of 50% even for a PCT cut-off of 0.25 ng/mL. In contrast, low CRP was strongly predictive of low PCT concentrations, particularly <0.5 ng/mL, with a negative predictive value of 97.6% at time of hospital admission and 100% 48 hours into hospital stay. CONCLUSIONS: CRP-guided PCT testing algorithms can reduce unnecessary PCT measurement and costs, supporting antimicrobial stewardship strategies in COVID-19.

Infection prevention and surgery in the pandemic era.

The COVID-19 pandemic has had a significant impact on surgical specialties. COVID-19 carries a significant risk to the surgical patient and the healthcare workers looking after them, with an increased incidence of pulmonary complications and mortality in patients who test positive perioperatively. Appropriate infection prevention and control measures are critical to ensure appropriate care is given and to reduce the risk of onward transmission. This article will discuss the measures that have been instigated and contributed to infection control in surgery, such as testing, patient isolation, personal protective equipment and ventilation. The COVID-19 pandemic has led to healthcare workers across many specialities working together to provide essential clinical care. This collaborative approach is critical to maintain excellent infection prevention and control practices required during this pandemic, which protect patients and preserve surgical services.

Promoting Adolescent Healthy Relationships (The About Us Program): Protocol for a Randomized Clinical Trial.

BACKGROUND: Romantic relationships play a critical role in adolescent development, and by middle adolescence, most young people have been involved in at least one romantic relationship, a context in which most sexual interactions occur. Research suggests adolescents lack positive models and skills related to building healthy relationships. OBJECTIVE: This project aims to test the impact of an innovative healthy relationships intervention, called About Us, implemented in school-based health centers (SBHCs) in California in a randomized controlled trial. METHODS: About Us is being tested using a 7-site, 2-group, parallel randomized controlled trial with a treatment versus control allocation ratio of 3:2 to assess the impact of the intervention relative to the standard of care among adolescents aged 14 to 18 years. Adolescents with active parental consent provide study assent at each of the 3 survey time points: baseline, 3 months postintervention, and 9 months postintervention. A stratified randomization procedure was used to ensure balance in key covariates and screening criteria across intervention groups. Through benchmark intent-to-treat analyses, we will examine the primary outcome of this study-the impact of About Us relative to the standard of care 9 months following the end of the intervention on the prevalence of vaginal or anal sex without condoms in the past 3 months. The secondary outcomes are four-fold: what is the impact of About Us relative to the standard of care 3 and 9 months following the end of the intervention, on (1) the prevalence of abstinence from vaginal or anal sex in the past 3 months, (2) composite scores of relationship communication and positive conflict resolution among participants involved in a relationship at baseline, (3) the prevalence of SBHC service use or information receipt in the past 3 months, and (4) composite scores of condom use intentions and attitudes regarding condoms and other birth control? Additionally, as part of our sensitivity analyses, two additional analyses will be implemented: modified intent-to-treat and complete case analysis. RESULTS: This project (ClinicalTrials.gov #NCT03736876) was funded in 2016 through the Family Youth Services Bureau as part of the Personal Responsibility Education Innovative Strategies program. Baseline data collection took place between February 2018 and March 2020, yielding a total of 5 cohorts and 533 study participants: 316 assigned to treatment and 217 assigned to control. Ongoing follow-up data collection continued through May 2021. CONCLUSIONS: About Us draws on developmental science to create a contextually and developmentally relevant program that addresses motivation and emotional influences in sexual decision-making. The intervention was designed for implementation within SBHCs, an understudied venue for relationship and sexual health promotion interventions. Unfortunately, COVID-19 pandemic restrictions led to school closures, interrupting ongoing programming, and in-person follow-up data collection, which has affected study attrition. TRIAL REGISTRATION: ClinicalTrials.gov NCT03736876; https://clinicaltrials.gov/ct2/show/NCT03736876. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/30499.

A highly effective reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assay for the rapid detection of SARS-CoV-2 infection.

The COVID-19 pandemic has illustrated the importance of simple, rapid and accurate diagnostic testing. This study describes the validation of a new rapid SARS-CoV-2 RT-LAMP assay for use on extracted RNA or directly from swab offering an alternative diagnostic pathway that does not rely on traditional reagents that are often in short supply during a pandemic. Analytical specificity (ASp) of this new RT-LAMP assay was 100% and analytical sensitivity (ASe) was between 1 × 101 and 1 × 102 copies per reaction when using a synthetic DNA target. The overall diagnostic sensitivity (DSe) and specificity (DSp) of RNA RT-LAMP was 97% and 99% respectively, relative to the standard of care rRT-PCR. When a CT cut-off of 33 was employed, above which increasingly evidence suggests there is a low risk of patients shedding infectious virus, the diagnostic sensitivity was 100%. The DSe and DSp of Direct RT-LAMP (that does not require RNA extraction) was 67% and 97%, respectively. When setting CT cut-offs of ≤33 and ≤25, the DSe increased to 75% and 100%, respectively, time from swab-to-result, CT < 25, was < 15 min. We propose that RNA RT-LAMP could replace rRT-PCR where there is a need for increased sample throughput and Direct RT-LAMP as a near-patient screening tool to rapidly identify highly contagious individuals within emergency departments and care homes during times of increased disease prevalence ensuring negative results still get laboratory confirmation.

Preliminary optimisation of a simplified sample preparation method to permit direct detection of SARS-CoV-2 within saliva samples using reverse-transcription loop-mediated isothermal amplification (RT-LAMP).

We describe the optimisation of a simplified sample preparation method which permits rapid and direct detection of SARS-CoV-2 RNA within saliva, using reverse-transcription loop-mediated isothermal amplification (RT-LAMP). Treatment of saliva samples prior to RT-LAMP by dilution 1:1 in Mucolyse™, followed by dilution in 10 % (w/v) Chelex© 100 Resin and a 98 °C heat step for 2 min enabled detection of SARS-CoV-2 RNA in positive saliva samples. Using RT-LAMP, SARS-CoV-2 RNA was detected in as little as 05:43 min, with no amplification detected in 3097 real-time reverse transcription PCR (rRT-PCR) negative saliva samples from staff tested within a service evaluation study, or for other respiratory pathogens tested (n = 22). Saliva samples can be collected non-invasively, without the need for skilled staff and can be obtained from both healthcare and home settings. Critically, this approach overcomes the requirement for, and validation of, different swabs and the global bottleneck in obtaining access to extraction robots and reagents to enable molecular testing by rRT-PCR. Such testing opens the possibility of public health approaches for effective intervention during the COVID-19 pandemic through regular SARS-CoV-2 testing at a population scale, combined with isolation and contact tracing.