SARS-CoV-2 detection using a nanobody-functionalized voltammetric device.

Background: An ongoing need during the COVID-19 pandemic has been the requirement for accurate and efficient point-of-care testing platforms to distinguish infected from non-infected people, and to differentiate SARS-CoV-2 infections from other viruses. Electrochemical platforms can detect the virus via its envelope spike protein by recording changes in voltammetric signals between samples. However, this remains challenging due to the limited sensitivity of these sensing platforms.

A mask-based diagnostic platform for point-of-care screening of Covid-19.

Diagnostics of SARS-CoV-2 infection using real-time reverse-transcription polymerase chain reaction (RT-PCR) on nasopharyngeal swabs is now well-established, with saliva-based testing being lately more widely implemented for being more adapted for self-testing approaches. In this study, we introduce a different concept based on exhaled breath condensate (EBC), readily collected by a mask-based sampling device, and detection with an electrochemical biosensor with a modular architecture that enables fast and specific detection and quantification of COVID-19. The face mask forms an exhaled breath vapor containment volume to hold the exhaled breath vapor in proximity to the EBC collector to enable a condensate-forming surface, cooled by a thermal mass, to coalesce the exhaled breath into a 200-500 μL fluid sample in 2 min.

Preanalytical Issues and Cycle Threshold Values in SARS-CoV-2 Real-Time RT-PCR Testing: Should Test Results Include These?

Since the emergence of SARS-CoV-2 pandemic, clinical laboratories worldwide are overwhelmed with SARS-CoV-2 testing using the current gold standard: real-time reverse-transcription polymerase chain reaction (RT-PCR) assays. The large numbers of suspected cases led to shortages in numerous reagents such as specimen transport and RNA extraction buffers. We try to provide some answers on how strongly preanalytical issues affect RT-PCR results by reviewing the utility of different transport buffer media and virus inactivation procedures and comparing the literature data with our own recent findings.

Relapsing Pityriasis Rosea With HHV-7 Reactivation in an 11-Year-Old Girl.

Pityriasis rosea (PR) usually presents as acute exanthema with oval erythematous-squamous lesions localized on the trunk, arms, and legs with spontaneous remission. We present an unusual case of PR with frequent relapses during a period of 7 years. An 11-year-old white female patient presented with many pruritic erythematous oval lesions on her trunk.

Comparison of two commercial quantitative PCR assays for EBV DNA detection and their correlation with the first WHO International Standard for EBV.

Purpose: There are few data on the performance of automated Epstein-Barr virus (EBV) PCR assays. This study compared EBV quantification for the kPCR PLX EBV DNA (kPCR; Siemens, France) and the EBV R-gene (R-gene; Argene, Biomerieux, France) assays and their correlation with the World Health Organization (WHO) standard.

Methodology: WHO International Standard for EBV (WHO standard) dilution panels in different matrices were submitted to nucleic acid extraction with Versant kPCR Molecular Systems SP followed by the kPCR assay, or to nucleic acid extraction with the MagNA Pure LC System or NucliSENS easyMag followed by the R-gene assay.