diagnostics
MinireviewUltrasensitive Diagnostics for Low-Density Asymptomatic Plasmodium falciparum Infections in Low-Transmission SettingsThe emergence of multidrug-resistant Plasmodium falciparum malaria in Southeast Asia (SEA) has accelerated regional malaria elimination efforts. Most malaria in this and other low-transmission settings exists in asymptomatic individuals, which conventional diagnostic tests lack the sensitivity to detect. This has led to the development of new ultrasensitive...
VirologyPerformance of Saliva Specimens for the Molecular Detection of SARS-CoV-2 in the Community Setting: Does Sample Collection Method Matter?Data on the performance of saliva specimens for diagnosing coronavirus disease 2019 (COVID-19) in ambulatory patients are scarce and inconsistent. We assessed saliva-based specimens for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) by reverse transcriptase PCR (RT-PCR) in the community setting and compared three different collection methods.
VirologyVariable Sensitivity of SARS-CoV-2 Molecular Detection in European Expert Laboratories: External Quality Assessment, June and July 2020During the ongoing coronavirus disease 2019 (COVID-19) outbreak, robust detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a key element for clinical management and to interrupt transmission chains. We organized an external quality assessment (EQA) of molecular detection of SARS-CoV-2 for European expert laboratories. An EQA panel composed of 12 samples, containing either SARS-CoV-2 at different concentrations...
Mycobacteriology and Aerobic ActinomycetesDiagnostic Accuracy Study of a Novel Blood-Based Assay for Identification of Tuberculosis in People Living with HIVA nonsputum triage test to rule out tuberculosis (TB) disease is a WHO high-priority diagnostic, and a combinatory score based on a 3-gene host signature has shown promise in discriminating TB from other illnesses. We evaluated the accuracy of an early-prototype cartridge assay (“Xpert MTB Host Response” or Xpert-MTB-HR-Prototype) of this 3-gene signature on biobanked blood samples from people living with HIV (PLHIV) against a...
VirologyStudy To Evaluate the Performance of a Point-of-Care Whole-Blood HIV Viral Load Test (SAMBA II HIV-1 Semi-Q Whole Blood)Remote areas of many low and middle income (LMI) countries have poor access to HIV viral load (HIV VL) testing. The SAMBA II (simple amplification-based assay) Semi-Q whole-blood test (Diagnostics for the Real World [DRW], Cambridge, UK) is a point-of-care assay, which uses leucodepletion technology to allow whole-blood testing in remote settings.
Mycobacteriology and Aerobic ActinomycetesComparative Analytical Evaluation of Four Centralized Platforms for the Detection of Mycobacterium tuberculosis Complex and Resistance to Rifampicin and IsoniazidFailure to rapidly identify drug-resistant tuberculosis (TB) increases the risk of patient mismanagement, the amplification of drug resistance, and ongoing transmission. We generated comparative analytical data for four automated assays for the detection of TB and multidrug-resistant TB (MDR-TB): Abbott RealTime MTB and MTB RIF/INH (Abbott), Hain Lifescience FluoroType MTBDR (Hain), BD Max MDR-TB (BD), and Roche cobas MTB and...
ImmunoassaysCOVID-19 Serology at Population Scale: SARS-CoV-2-Specific Antibody Responses in SalivaSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of an ongoing pandemic that has infected over 36 million and killed over 1 million people. Informed implementation of government public health policies depends on accurate data on SARS-CoV-2 immunity at a population scale. We hypothesized that detection of SARS-CoV-2 salivary antibodies could serve as a noninvasive alternative to serological testing for monitoring...
VirologyComparison of Upper Respiratory Viral Load Distributions in Asymptomatic and Symptomatic Children Diagnosed with SARS-CoV-2 Infection in Pediatric Hospital Testing ProgramsThe distribution of upper respiratory viral loads (VL) in asymptomatic children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unknown. We assessed PCR cycle threshold (Ct) values and estimated VL in infected asymptomatic children diagnosed in nine pediatric hospital testing programs. Records for asymptomatic and symptomatic patients with positive clinical SARS-CoV-2 tests were reviewed. Ct values were (i...
VirologyMetagenomic Sequencing To Detect Respiratory Viruses in Persons under Investigation for COVID-19Broad testing for respiratory viruses among persons under investigation (PUIs) for SARS-CoV-2 has been performed inconsistently, limiting our understanding of alternative viral infections and coinfections in these patients. RNA metagenomic next-generation sequencing (mNGS) offers an agnostic tool for the detection of both SARS-CoV-2 and other RNA respiratory viruses in PUIs. Here, we used RNA mNGS to assess the frequencies of...
MycologyDiagnostic Accuracy of the Biosynex CryptoPS Cryptococcal Antigen Semiquantitative Lateral Flow Assay in Patients with Advanced HIV DiseaseHigh cryptococcal antigen (CrAg) titers in blood are associated with subclinical meningitis and mortality in CrAg-positive individuals with advanced HIV disease (AHD). We evaluated a novel semiquantitative lateral flow assay (LFA), CryptoPS, that may be able to identify individuals with high CrAg titers in a cohort of AHD patients undergoing CrAg screening. In a prospective cohort of patients with AHD (CD4 cell count, ≤200/μl) receiving...