Scalable RT-LAMP-based SARS-CoV-2 testing for infection surveillance with applications in pandemic preparedness.

Throughout the SARS-CoV-2 pandemic, limited diagnostic capacities prevented sentinel testing, demonstrating the need for novel testing infrastructures. Here, we describe the setup of a cost-effective platform that can be employed in a high-throughput manner, which allows surveillance testing as an acute pandemic control and preparedness tool, exemplified by SARS-CoV-2 diagnostics in an academic environment. The strategy involves self-sampling based on gargling saline, pseudonymized sample handling, automated RNA extraction, and viral RNA detection using a semiquantitative multiplexed colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay with an analytical sensitivity comparable with RT-qPCR. We provide standard operating procedures and an integrated software solution for all workflows, including sample logistics, analysis by colorimetry or sequencing, and communication of results. We evaluated factors affecting the viral load and the stability of gargling samples as well as the diagnostic sensitivity of the RT-LAMP assay. In parallel, we estimated the economic costs of setting up and running the test station. We performed > 35,000 tests, with an average turnover time of < 6 h from sample arrival to result announcement. Altogether, our work provides a blueprint for fast, sensitive, scalable, cost- and labor-efficient RT-LAMP diagnostics, which is independent of potentially limiting clinical diagnostics supply chains.

MiR-5189-3p Suppresses cell Proliferation, Invasion and Migration Through Targeting EIF5A2 in Laryngeal Squamous Cell Carcinoma.

A growing body of evidence suggests that miR-5189-3p plays a critical role in multiple diseases. This study aimed to investigate the function of miR-5189-3p in laryngeal squamous cell carcinoma (LSCC) and explore its underlying mechanisms. qRT-PCR was designed to determine the expression levels of miR-5189-3p and eukaryotic translation initiation factor 5A2 (EIF5A2), while CCK-8 assay was performed to measure the effects of miR-5189-3p on cell proliferation. Transwell assay was performed to evaluate cell invasion as well as migration, and wound healing assay was applied to demonstrate cell migratory ability. Target gene prediction and luciferase reporter assay were developed to screen the possible target gene of miR-5189-3p, and Western blot was designed to measure EIF5A2 protein expression. MiR-5189-3p was down-regulated in LSCC tissues and cell lines. Up-regulation of miR-5189-3p notably inhibited cell proliferation, invasion, and migration in HEP2 and FADU cells. EIF5A2 was the potential downstream gene of miR-5189-3p, and overexpression of miR-5189-3p apparently reduced EIF5A2 expression. Moreover, reintroduction of EIF5A2 rescued the tumor suppressive effects of miR-5189-3p. MiR-5189-3p functions as a tumor inhibitor in LSCC progression via directly regulating EIF5A2 and may be a potential therapeutic target for LSCC.

ATB0,+-targeted delivery of triptolide prodrugs for safer and more effective pancreatic cancer therapy.

Triptolide (TP) is a diterpene epoxide component extracted from Tripterygium wilfordii and has been shown to possess an impressive anticancer effect. However, TP has not yet entered any clinic trials due to the severe adverse effects that resulted from the off-target absorption and distribution found in animal studies. In this study, we designed and synthesized three amino acids (tryptophan, valine, and lysine) based TP prodrugs to target ATB0,+ which are highly expressed in pancreatic cancer cells for more effective pancreatic cancer therapy. The stability, uptake profiles, uptake mechanism, and cancer-killing ability were studied in vitro. All three prodrugs showed increased uptake and enhanced cytotoxicity in pancreatic cancer cells, but not in normal pancreatic cells. The difference in killing effect on normal and cancer cells was attributed to pancreatic cancer over-expressed ATB0,+-mediated uptake. Specifically, tryptophan-conjugated TP prodrug (TP-Trp) showed the highest uptake and the best cancer cell killing effect, considered as the best candidate. The present study provided the proof-of-concept of exploiting TP prodrug to target ATB0,+ for pancreatic cancer-selective delivery and treatment.

A mobile terminal application program was used for endotracheal tube cuff pressure measurement.

We studied the application of a mobile terminal application program in endotracheal tube (ETT) cuff pressure measurement to improve the implementation rate of scientific ETT cuff pressure measurement and to ensure that the pressure falls within the recommended range. A pre-post controlled study lasting for 18 months was undertaken in a 40-bed general intensive care unit (GICU). This included a 6-month baseline period (baseline group) and a 6-month intervention period (intervention group). The mobile terminal application program was applied to monitor the cuff pressure of endotracheal intubation as an intervention measure during the intervention period. ETT pressure was the main outcome measure, while gender, age, causes for ICU admission, sedation score, duration of prior intubation, size of ETT, and number of VAP patients were secondary outcomes. ETT cuff pressure was monitored 742 times in both the baseline group and the intervention group. A total of 56.9% of the cuff pressure measurements in the baseline group were within the recommended range, while 78.4% of measurements in the intervention group were within the recommended range, reflecting a statistically significant difference (P < 0.05). The application of the mobile terminal application program used for ETT cuff pressure measurement could improve the percentage of ETT cuff pressure measurements falling within the recommended range.

Effects of ketoconazole, voriconazole, and itraconazole on the pharmacokinetics of apatinib in rats.

We investigated the effect of azole antifungal drugs (ketoconazole, voriconazole, and itraconazole) on the pharmacokinetics of apatinib in rats. The rats in ketoconazole, voriconazole, and itraconazole groups received single-dose apatinib 30 mg/kg after the oral administration of ketoconazole, voriconazole, and itraconazole, respectively. Co-administration of ketoconazole or voriconazole significantly increased the apatinib Cmax and AUC(0-t) and decreased the clearance. Co-administration of itraconazole did not significantly affect the pharmacokinetics parameters of apatinib. It could be concluded that both ketoconazole and voriconazole significantly increase the exposure of apatinib, and affect the pharmacokinetics of apatinib in rat. Apatinib can be co-administered with itraconazole, but ketoconazole and voriconazole should be avoided if possible or be underwent therapeutic drug monitoring of apatinib. A further clinical study should be conducted to investigate the inhibitory effect of azole antifungal drugs on the apatinib plasma concentration.

[Effects of Shengmai Jianghuang San on intestinal flora in nude mice with radio resistant cells of nasopharyngeal carcinoma].

Modern pharmacological studies have shown that Shengmai San has the effects of enhancing immunity and improving blood circulation, and Curcumae Longae Rhizoma(Jianghuang) has anti-inflammatory, anti-cancer, anti-oxidation and other functions. Shengmai San combined with Jianghuang is a new research direction in the study of anti-tumor of traditional Chinese medicines. The main treatment for nasopharyngeal carcinoma is radiation therapy, but radiation therapy can cause a variety of side effects, and it also changes the composition of the intestinal flora. In this study, the 16 s rDNA sequencing platform was used to perform macro-sequence sequencing of the intestinal flora samples of nude mice bearing the veins of Shengmai Jianghuang San, and then the results of intestinal flora data were analyzed to investigate the effect of Shengmai Jianghuang San on tumors. The results showed that Shengmai Jianghuang San combined with irradiation could enhance the therapeutic effect of tumor treatment. Radiation therapy would reduce the total number and diversity of intestinal flora in nude mice, and also change the structure of the flora. Shengmai Jianghuang San could protect the diversity of colonies, and also partially restore the colony imbalance caused by irradiation. This study provides a research idea for Shengmai Jianghuang San as a sensitizing adjuvant for radiotherapy of nasopharyngeal carcinoma.

Sodium arsenite exposure inhibits histone acetyltransferase p300 for attenuating H3K27ac at enhancers in mouse embryonic fibroblast cells.

Both epidemiological investigations and animal studies have linked arsenic-contaminated water to cancers, including skin, liver and lung cancers. Besides genotoxicity, arsenic exposure-related pathogenesis of disease is widely considered through epigenetic mechanisms; however, the underlying mechanism remains to be determined. Herein we explore the initial epigenetic changes via acute sodium arsenite (As) exposures of mouse embryonic fibroblast (MEF) cells and histone H3K79 methyltransferase Dot1L knockout (Dot1L-/-) MEF cells. Our RNA-seq and Western blot data demonstrated that, in both cell lines, acute As exposure abolished histone acetyltransferase p300 at the RNA level and subsequent protein level. Consequently, p300-specific main target histone H3K27ac, a marker separating active from poised enhancers, decreased dramatically as validated by both Western blot and ChIP-qPCR/seq analyses. Concomitantly, H3K4me1 as another well-known marker for enhancers also showed significant decreases, suggesting an underappreciated crosstalk between H3K4me1 and H3K27ac involved in As exposure. Significantly, As exposure-reduced H3K27ac and H3K4me1 inhibited the expression of genes including EP300 itself and Kruppel Like Factor 4(Klf4) that both are tumor suppressor genes. Collectively, our investigations identified p300 as an internal bridging factor within cells to sense external environmental As exposure to alter chromatin, thereby changing gene transcription for disease pathogenesis.

Determination of rivaroxaban, apixaban and edoxaban in rat plasma by UPLC-MS/MS method.

To establish a rapid and sensitive ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method for the determination of rivaroxaban, apixaban and edoxaban in rat plasma. The analytes and the internal standard (diazepam) were separated on an Acquity UPLC BEH C18 chromatography column (2.1 mm × 50 mm, 1.7 µm) using gradient elution with a mobile phase of acetonitrile and 0.1 % formic acid in water at a flow rate of 0.4 mL/min. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring mode to monitor the precursor-to-product ion transitions of m/z 436.1 â†’ 145.1 for rivaroxaban, m/z 460.0 â†’ 443.1 for apixaban, m/z 548.2 â†’ 366.1 for edoxaban and m/z 285.2 â†’ 193.1 for diazepam (IS) using a positive electrospray ionization interface. The method was validated over a concentration range of 1.0-200 ng/mL for rivaroxaban, 1.0-100 ng/mL for apixaban and 1.0-500 ng/mL for edoxaban. Total time for each chromatograph was 3.5 min. The intra- and inter-day precision and accuracy of the quality control samples at low, medium, and high concentration levels exhibited relative standard deviations <10.5 % and the accuracy values ranged from -9.9 to 11.3 %. The method was successfully applied to a pharmacokinetic study of rivaroxaban, apixaban and edoxaban in rats.

Does age matter? Comparison of neurobehavioral effects of paraquat exposure on postnatal and adult C57BL/6 mice.

Epidemiological studies have revealed that environmentally relevant low levels of paraquat (PQ) exposure is listed on the etiology of neurological disorders such as Parkinson's disease (PD). The behavioral effects of PQ are of current interest, especially when exposure occurs in the period of early stage of life. To characterize whether and how age affects neurobehavioral performances of mice after PQ exposure, 21 days postnatal (PN21) and adult male C57BL/6 mice were daily administrated by oral gavage with 0 mg/kg (saline, control), 5 mg/kg or 10 mg/kg of PQ for 28 consecutive days. Survival rate and body weight were analyzed. Subsequently, mice were subjected to Morris water maze tests (MWM). The results showed that mice exposed to PQ had significantly longer latencies than those in the control group, with a dose-dependent manner. Furthermore, PN21 mice tended to have longer latencies than adult mice in the same dose group. Our data suggested that PQ exposure induced significant learning and memory impairment and more severely in PN21 mice when compared with adult mice.

The role of chicken ovalbumin upstream promoter transcription factor II in the regulation of hepatic fatty acid oxidation and gluconeogenesis in newborn mice.

Chicken ovalbumin upstream promoter transcription factor II (COUP-TFII) is an orphan nuclear receptor involved in the control of numerous functions in various organs (organogenesis, differentiation, metabolic homeostasis, etc.). The aim of the present work was to characterize the regulation and contribution of COUP-TFII in the control of hepatic fatty acid and glucose metabolisms in newborn mice. Our data show that postnatal increase in COUP-TFII mRNA levels is enhanced by glucagon (via cAMP) and PPARα. To characterize COUP-TFII function in the liver of suckling mice, we used a functional (dominant negative form; COUP-TFII-DN) and a genetic (shRNA) approach. Adenoviral COUP-TFII-DN injection induces a profound hypoglycemia due to the inhibition of gluconeogenesis and fatty acid oxidation secondarily to reduced PEPCK, Gl-6-Pase, CPT I, and mHMG-CoA synthase gene expression. Using the crossover plot technique, we show that gluconeogenesis is inhibited at two different levels: 1) pyruvate carboxylation and 2) trioses phosphate synthesis. This could result from a decreased availability in fatty acid oxidation arising cofactors such as acetyl-CoA and reduced equivalents. Similar results are observed using the shRNA approach. Indeed, when fatty acid oxidation is rescued in response to Wy-14643-induced PPARα target genes (CPT I and mHMG-CoA synthase), blood glucose is normalized in COUP-TFII-DN mice. In conclusion, this work demonstrates that postnatal increase in hepatic COUP-TFII gene expression is involved in the regulation of liver fatty acid oxidation, which in turn sustains an active hepatic gluconeogenesis that is essential to maintain an appropriate blood glucose level required for newborn mice survival.

Fine mapping and whole-exome sequencing of a familial cortical myoclonic tremor with epilepsy family.

Familial cortical myoclonic tremor with epilepsy (FCMTE) is an autosomal dominant epilepsy syndrome. Four loci, including 8q24 (FCMTE1), 2p11.1-q12.2 (FCMTE2), 5p15.31-p15.1 (FCMTE3), and 3q26.32-3q28 (FCMTE4) were previously reported. Herein, we report a new FCMTE1 pedigree from Chinese population with its clinical and genetic study results. Whole genome scan was performed to identify the causative gene region and copy number variants. Whole-exome sequencing was used to identify the causative gene. There were twelve affected members alive in this FCMTE1 pedigree. Nine affected members had both cortical myoclonic tremor and epilepsy, while three affected members had only cortical myoclonic tremor. Electrophysiologic examinations manifested giant somatosensory evoked potentials and long-latency cortical reflex in some affected members. Whole genome scan identified a 20.4 Mb causative gene region at 8q22.3-q24.13. No copy number variants were identified as the causative mutation. Whole-exome sequencing identified a co-segregated mutation (c.206A>T; p.Y69F) in the SLC30A8 gene. However, the evidence supporting this gene as the causative gene of FCMTE1 is not enough. We report the first Chinese FCMTE1 pedigree. No copy number variants, point mutation or small insertion/deletion were detected in the identified region that showed an association with FCMTE1. Further studies could focus on other possible genetic mechanisms while the association between the SLC30A8 and FCMTE1 needs further evidence.

Characterization of paraquat-induced miRNA profiling response in hNPCs undergoing proliferation.

Aberration during the development of the central nervous system (CNS) due to environmental factors underlies a variety of adverse developmental outcomes. Paraquat (PQ) is a widely studied neurotoxicant that perturbs the normal structure/function of adult CNS. Yet, the impacts of PQ exposure on the developing CNS remain unclear. miRNAs represent a class of small non-coding RNA molecules involved in the regulation of neural development. Thus in the present study, we analyzed the impacts of PQ on the miRNome of human neural progenitor cells (hNPCs) during proliferation by using the Exiqon miRCURY™ LNA Array. A total of 66 miRNAs were identified as differentially expressed in proliferating hNPCs upon PQ treatment. miRTarBase prediction identified 1465 mRNAs, including several genes (e.g., nestin, sox1, ngn1) previously proved to be associated with the neural proliferation and differentiation, as target genes of PQ-induced differentially expressed miRNAs. The database for annotation, visualization and integrated discovery (DAVID) bioinformatics analysis showed that target genes were enriched in regulation of cell proliferation and differentiation, cell cycle and apoptosis as well as tumor protein 53 (p53), Wnt, Notch and mitogen-activated protein kinases (MAPK) signaling pathways (p < 0.001). These findings were confirmed by real-time RT-PCR. Based on our results we conclude that PQ-induced impacts on the miRNA profiling of hNPCs undergoing proliferation may underlie the developmental neurotoxicity of PQ.

[Micro RNA alteration after paraquat induced PC12 cells damage and regulatory mechanism of bcl-2].

OBJECTIVE: To investigate the effects of paraquat on microRNA expressions in PCl2 cells, and to explore the regulatory mechanism of bcl-2. METHODS: We used PC12 cells as a popular in vitro cell model system for characterizing the dopaminergic neuron. After 24 h treatment with different concentrations of PQ (0, 62.5 ümol/L), expression difference of microRNA was detected by microarray and examined by real-time quantitative PCR (RT-PCR). Cell apoptosis was analyzed with flow cytometry (FCM) and the relative levels of miR-34a, miR-Let-7e were measured by RT-RCR following the PCl2 cells treatment with 0, 62.5, 125, 250, 500, 1000 ümol/L PQ. Meanwhile, the protein expression of bcl-2 was evaluated by western blot according to forecasting targets analysis databases. RESULTS: Cell viability decreased and cell apoptosis increased with increasing PQ concentrations (from 125 to 1000 ümol/L) in a dose-dependent manner (P < 0.05 or P < 0.01). MiRNA microarray showed that after 62.5 ümol/L PQ treatment, 11 miRNAs were significantly up-regulated while 8 miRNAs were down-regulated compared with control (P < 0.01). We chose miR-34a, miR-Let-7e which appeared most remarkable changes in microarray to examine by RT-PCR. It revealed that the level of miR-34a gradually ascended while miR-Let-7e declined after PQ treatment, which are accordant to the microarray results. The protein expression of bcl-2 treated with PQ significantly decreased compared with control and presented a negative correlation with the expression of miR-34a (P < 0.05 or P < 0.01). CONCLUSION: The alteration of miRNAs expression may be involved in the neurotoxicity of PQ. Especially, mir-34a negatively regulated the level of bcl-2, and thus plays a key role in PQ-induced cell apoptosis.

[Oral exposure of fluorochloridone caused testes damage of Sparague-Dawley rats].

OBJECTIVE: To investigate the effects of fluorochloridone (FLC) exposure on the testes of adult Sprague-Dawley (SD) rats. METHODS: Forty male SD rats were randomly divided into four groups. These groups, each of 10 male rats, were separately given FLC by gavage at a dose of 0 (control), 30, 150, or 750 mg/kg once daily for 28 d. The oxidative stress biomarkers in the testes were measured by spectrophotometry. The pathological changes in testicular tissues were evaluated under the light and electric microscopes. The cauda epididymal sperm count was determined. The testicular toxicity of FLC was assessed accordingly. RESULTS: Compared with the control group, the 750 mg/kg FLC group had significantly lower testicular weight and organ coefficient, epididymal weight, and cauda epididymal sperm count (P < 0.05 or P < 0.01), the 150 and 750 mg/kg FLC groups had significantly increased malonaldehyde content (P < 0.05 or P < 0.01), each exposed group had a significantly reduced glutathione (GSH) level (P < 0.05 or P < 0.01), the 750 mg/kg FLC group had significantly reduced activities of superoxide dismutase (SOD), catalase (CAT), GSH peroxidase, GSH S-transferase (GSH-ST), and GSH reductase (GSH-GR) (P < 0.05 or P < 0.01), the 150 mg/kg FLC group showed significant decreases in the activities of all antioxidant enzymes except GSH-GR (P < 0.05 or P < 0.01), and the 30 mg/kg FLC group showed significant decreases in the activities of SOD and CAT (P < 0.05 or P < 0.01). Furthermore, seminiferous epithelial degeneration, Sertoli cell vacuolization, spermatogenic cell loss, and nuclear damage were observed under the light and electronic microscopes in the 150 and 750 mg/kg FLC groups. CONCLUSION: FLC could damage the testes of adult rats by inducting oxidative stress. This research provided clues and directions for further exploration of the mechanism of FLC testicular toxicity.

Uncertainty reduction for precipitation prediction in North America.

Large differences in projected future annual precipitation increases in North America exists across 27 CMIP6 models under four emission scenarios. These differences partly arise from weak representations of land-atmosphere interactions. Here we demonstrate an emergent constraint relationship between annual growth rates of future precipitation and growth rates of historical temperature. The original CMIP6 projections show 0.49% (SSP126), 0.98% (SSP245), 1.45% (SSP370) and 1.92% (SSP585) increases in precipitation per decade. Combining observed warming trends, the constrained results show that the best estimates of future precipitation increases are more likely to reach 0.40-0.48%, 0.83-0.93%, 1.29-1.45% and 1.70-1.87% respectively, implying an overestimated future precipitation increases across North America. The constrained results also are narrow the corresponding uncertainties (standard deviations) by 13.8-31.1%. The overestimated precipitation growth rates also reveal an overvalued annual growth rates in temperature (6.0-13.2% or 0.12-0.37°C) and in total evaporation (4.8-14.5%) by the original models' predictions. These findings highlight the important role of temperature for accurate climate predictions, which is important as temperature from current climate models' simulations often still have systematic errors.

Correction: Comparison of Four Active SARS-CoV-2 Surveillance Strategies in Representative Population Sample Points: Two-Factor Factorial Randomized Controlled Trial.

[This corrects the article DOI: 10.2196/44204.].

Constitutive hepcidin expression prevents iron overload in a mouse model of hemochromatosis.

Hereditary hemochromatosis is a prevalent genetic disorder of iron hyperabsorption leading to hyperferremia, tissue iron deposition and complications including cirrhosis, hepatocarcinoma, cardiomyopathy and diabetes. Most individuals affected with hereditary hemochromatosis are homozygous with respect to a missense mutation that disrupts the conformation of HFE, an atypical HLA class I molecule (ref. 1; OMIM 235200). Mice lacking Hfe or producing a C282Y mutant Hfe protein develop hyperferremia and have high hepatic iron levels. In both humans and mice, hereditary hemochromatosis is associated with a paucity of iron in reticuloendothelial cells. It has been suggested that HFE modulates uptake of transferrin-bound iron by undifferentiated intestinal crypt cells, thereby programming the absorptive capacity of enterocytes derived from these cells; however, this model is unproven and controversial. Hepcidin, a peptide hormone (HAMP; OMIM 606464), seems to act in the same regulatory pathway as HFE. Although expression of mouse Hamp is normally greater during iron overload, Hfe-/- mice have inappropriately low expression of Hamp. We crossed Hfe-/- mice with transgenic mice overexpressing Hamp and found that Hamp inhibited the iron accumulation normally observed in the Hfe-/- mice. This argues against the crypt programming model and suggests that failure of Hamp induction contributes to the pathogenesis of hemochromatosis, providing a rationale for the use of HAMP in the treatment of this disease.

Effect of Shengmai Yin on Epithelial-Mesenchymal Transition of Nasopharyngeal Carcinoma Radioresistant Cells.

OBJECTIVE: To investigate the mechanism by which Chinese medicine Shengmai Yin (SMY) reverses epithelial-mesenchymal transition (EMT) through lipocalin-2 (LCN2) in nasopharyngeal carcinoma (NPC) cells CNE-2R. METHODS: Morphological changes in EMT in CNE-2R cells were observed under a microscope, and the expressions of EMT markers were detected using quantitative real-time PCR (RT-qPCR) and Western blot assays. Through the Gene Expression Omnibus dataset and text mining, LCN2 was found to be highly related to radiation resistance and EMT in NPC. The expressions of LCN2 and EMT markers following SMY treatment (50 and 100 µ g/mL) were detected by RT-qPCR and Western blot assays in vitro. Cell proliferation, migration, and invasion abilities were measured using colony formation, wound healing, and transwell invasion assays, respectively. The inhibitory effect of SMY in vivo was determined by observing a zebrafish xenograft model with a fluorescent label. RESULTS: The CNE-2R cells showed EMT transition and high expression of LCN2, and the use of SMY (5, 10 and 20 µ g/mL) reduced the expression of LCN2 and reversed the EMT in the CNE-2R cells. Compared to that of the CNE-2R group, the proliferation, migration, and invasion abilities of SMY high-concentration group were weakened (P<0.05). Moreover, SMY mediated tumor growth and metastasis in a dose-dependent manner in a zebrafish xenograft model, which was consistent with the in vitro results. CONCLUSIONS: SMY can reverse the EMT process of CNE-2R cells, which may be related to its inhibition of LCN2 expression. Therefore, LCN2 may be a potential diagnostic marker and therapeutic target in patients with NPC.

Comparison of Four Active SARS-CoV-2 Surveillance Strategies in Representative Population Sample Points: Two-Factor Factorial Randomized Controlled Trial.

BACKGROUND: The COVID-19 pandemic is characterized by rapid increases in infection burden owing to the emergence of new variants with higher transmissibility and immune escape. To date, monitoring the COVID-19 pandemic has mainly relied on passive surveillance, yielding biased epidemiological measures owing to the disproportionate number of undetected asymptomatic cases. Active surveillance could provide accurate estimates of the true prevalence to forecast the evolution of the pandemic, enabling evidence-based decision-making. OBJECTIVE: This study compared 4 different approaches of active SARS-CoV-2 surveillance focusing on feasibility and epidemiological outcomes. METHODS: A 2-factor factorial randomized controlled trial was conducted in 2020 in a German district with 700,000 inhabitants. The epidemiological outcome comprised SARS-CoV-2 prevalence and its precision. The 4 study arms combined 2 factors: individuals versus households and direct testing versus testing conditioned on symptom prescreening. Individuals aged ≥7 years were eligible. Altogether, 27,908 addresses from 51 municipalities were randomly allocated to the arms and 15 consecutive recruitment weekdays. Data collection and logistics were highly digitized, and a website in 5 languages enabled low-barrier registration and tracking of results. Gargle sample collection kits were sent by post. Participants collected a gargle sample at home and mailed it to the laboratory. Samples were analyzed with reverse transcription loop-mediated isothermal amplification (RT-LAMP); positive and weak results were confirmed with real-time reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Recruitment was conducted between November 18 and December 11, 2020. The response rates in the 4 arms varied between 34.31% (2340/6821) and 41.17% (2043/4962). The prescreening classified 16.61% (1207/7266) of the patients as COVID-19 symptomatic. Altogether, 4232 persons without prescreening and 7623 participating in the prescreening provided 5351 gargle samples, of which 5319 (99.4%) could be analyzed. This yielded 17 confirmed SARS-CoV-2 infections and a combined prevalence of 0.36% (95% CI 0.14%-0.59%) in the arms without prescreening and 0.05% (95% CI 0.00%-0.108%) in the arms with prescreening (initial contacts only). Specifically, we found a prevalence of 0.31% (95% CI 0.06%-0.58%) for individuals and 0.35% (95% CI 0.09%-0.61%) for households, and lower estimates with prescreening (0.07%, 95% CI 0.0%-0.15% for individuals and 0.02%, 95% CI 0.0%-0.06% for households). Asymptomatic infections occurred in 27% (3/11) of the positive cases with symptom data. The 2 arms without prescreening performed the best regarding effectiveness and accuracy. CONCLUSIONS: This study showed that postal mailing of gargle sample kits and returning home-based self-collected liquid gargle samples followed by high-sensitivity RT-LAMP analysis is a feasible way to conduct active SARS-CoV-2 population surveillance without burdening routine diagnostic testing. Efforts to improve participation rates and integration into the public health system may increase the potential to monitor the course of the pandemic. TRIAL REGISTRATION: Deutsches Register Klinischer Studien (DRKS) DRKS00023271; https://tinyurl.com/3xenz68a. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1186/s13063-021-05619-5.

Phase I study of a non-S2P SARS-CoV-2 mRNA vaccine LVRNA009 in Chinese adults.

BACKGROUND: COVID-19 caused by SARS-CoV-2 is a great threat to public health. We present the safety and immunogenicity data from a phase I trial in China of an mRNA vaccine (LVRNA009). METHODS: In the single-centre, double-blind, placebo-controlled and dose-escalation study, 72 healthy unvaccinated adults aged 18-59 years were randomized (3:1) to receive LVRNA009 with one of three vaccine dosage (25, 50 and 100 µg) or placebo, to evaluate for the safety, tolerability and immunogenicity of LVRNA009. RESULTS: All these participants received two injections 28 days apart. No adverse events higher than grade 2 were reported during the study. A total of 30 participants (42 %) reported solicited adverse reactions during the first 14 days after vaccinations. Of the events reported, fever (n = 11, 15 %) was the most common systemic adverse reaction, and pain at the injection site (n = 17, 24 %) was the most frequent solicited local adverse reaction. Anti-S-protein IgG and neutralising antibodies were observed to have been induced 14 days after the first dose, significantly increased 7 days after the second dose, and remained at a high level 28 days after the second dose. Specific T-cell responses peaked 7 days and persisted 28 days after second vaccination. CONCLUSION: LVRNA009 has demonstrated promising results in safety and tolerability at all three dose levels among Chinese adults. LVRNA009 at three dose levels could rapidly induce strong humoral and cellular immune responses, including binding and neutralising antibody production and IFN- γ secretion, which showed good immunogenicity. CLINICAL TRIAL REGISTRATION NUMBER: Clinicaltrials.gov NCT05364047; Chictr.org.cn ChiCTR2100049349.