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1.
Front Med (Lausanne) ; 9: 829799, 2022.
Article in English | MEDLINE | ID: covidwho-1785361

ABSTRACT

Background: Non-pharmaceutical interventions (NPIs) to mitigate COVID-19 can impact the circulation of influenza viruses. There is a need to describe the activity of influenza and its subtypes during the COVID-19 pandemic to aid in the development of influenza prevention and control measures in the next influenza season. Method: Data from pathogenic surveillance performed by the Chinese National Influenza Center from January 2016 to August 2021 were extracted and stratified by type and subtype for northern China and southern China. The distribution of influenza activity and circulating subtypes were described during the COVID-19 pandemic, and data from 2016 to 2019 were used for comparisons. Results: Influenza activity declined rapidly and then rose slowly during the COVID-19 pandemic in China. The distribution of influenza subtypes changed from A-dominant to B/Victoria-dominant after the COVID-19 outbreak. Discussion: Whether the B/Yamagata lineage has disappeared from China deserves more attention in future virologic monitoring programs. The influenza vaccination campaign in the 2021-2022 season is an important means by which to reduce the proportion of susceptible people and limit the damage that potentially greater and earlier circulation of the virus could cause.

2.
Geoscience Frontiers ; : 101384, 2022.
Article in English | ScienceDirect | ID: covidwho-1757360

ABSTRACT

Underground subway platforms are among the world’s busiest public transportation systems, but the airborne transmission mechanism of respiratory infections on these platforms has been rarely studied. Here, computational fluid dynamics (CFD) modeling is used to investigate the airflow patterns and infection risks in an island platform under two common ventilation modes: Mode 1- both sides have air inlets and outlets;Mode 2- air inlets are present at the two sides and outlets are present in the middle. Under the investigated scenario, airflow structure is characterized by the ventilation jet and human thermal plumes. Their interaction with the infector’s breathing jet imposes the front passenger under the highest exposure risk by short-range airborne route, with intake fractions up to 2.57% (oral breathing) or 0.63% (nasal breathing) under Mode 1;oral breathing of the infector may impose higher risks for the front passenger compared with nasal breathing. Pathogen are efficiently diluted as they travel further, in particular to adjacent crowds. The maximum and median value of intake fractions of passengers in adjacent crowds are respectively 0.093% and 0.016% (oral breathing), and 0.073% and 0.014% (nasal breathing) under Mode 1. Compared with Mode 1, the 2nd mode minimizes the interaction of ventilation jet and breathing jet, where the maximum intake fraction is only 0.34%, and the median value in the same crowd and other crowds are reduced by 23-63%. Combining published quanta generation rate data of COVID-19 and influenza infectors, the predicted maximum and median infection risks for passengers in the same crowds are respectively 1.46%−40.23% and 0.038%−1.67% during the 3−10 min waiting period, which are more sensitive to ventilation rate and exposure time compared with return air. This study can provide practical guidance for the prevention of respiratory infections in subway platforms.

3.
J Virol ; 96(4): e0196921, 2022 02 23.
Article in English | MEDLINE | ID: covidwho-1702819

ABSTRACT

Unlike SARS-CoV-1 and MERS-CoV, infection with SARS-CoV-2, the viral pathogen responsible for COVID-19, is often associated with neurologic symptoms that range from mild to severe, yet increasing evidence argues the virus does not exhibit extensive neuroinvasive properties. We demonstrate SARS-CoV-2 can infect and replicate in human iPSC-derived neurons and that infection shows limited antiviral and inflammatory responses but increased activation of EIF2 signaling following infection as determined by RNA sequencing. Intranasal infection of K18 human ACE2 transgenic mice (K18-hACE2) with SARS-CoV-2 resulted in lung pathology associated with viral replication and immune cell infiltration. In addition, ∼50% of infected mice exhibited CNS infection characterized by wide-spread viral replication in neurons accompanied by increased expression of chemokine (Cxcl9, Cxcl10, Ccl2, Ccl5 and Ccl19) and cytokine (Ifn-λ and Tnf-α) transcripts associated with microgliosis and a neuroinflammatory response consisting primarily of monocytes/macrophages. Microglia depletion via administration of colony-stimulating factor 1 receptor inhibitor, PLX5622, in SARS-CoV-2 infected mice did not affect survival or viral replication but did result in dampened expression of proinflammatory cytokine/chemokine transcripts and a reduction in monocyte/macrophage infiltration. These results argue that microglia are dispensable in terms of controlling SARS-CoV-2 replication in in the K18-hACE2 model but do contribute to an inflammatory response through expression of pro-inflammatory genes. Collectively, these findings contribute to previous work demonstrating the ability of SARS-CoV-2 to infect neurons as well as emphasizing the potential use of the K18-hACE2 model to study immunological and neuropathological aspects related to SARS-CoV-2-induced neurologic disease. IMPORTANCE Understanding the immunological mechanisms contributing to both host defense and disease following viral infection of the CNS is of critical importance given the increasing number of viruses that are capable of infecting and replicating within the nervous system. With this in mind, the present study was undertaken to evaluate the role of microglia in aiding in host defense following experimental infection of the central nervous system (CNS) of K18-hACE2 with SARS-CoV-2, the causative agent of COVID-19. Neurologic symptoms that range in severity are common in COVID-19 patients and understanding immune responses that contribute to restricting neurologic disease can provide important insight into better understanding consequences associated with SARS-CoV-2 infection of the CNS.


Subject(s)
Angiotensin-Converting Enzyme 2/immunology , COVID-19/immunology , Central Nervous System Viral Diseases/immunology , Microglia/immunology , SARS-CoV-2/physiology , Virus Replication/immunology , Angiotensin-Converting Enzyme 2/genetics , Animals , COVID-19/genetics , Central Nervous System/immunology , Central Nervous System/virology , Central Nervous System Viral Diseases/genetics , Central Nervous System Viral Diseases/virology , Chemokines/genetics , Chemokines/immunology , Disease Models, Animal , Humans , Mice , Mice, Transgenic , Microglia/virology , Neurons/immunology , Neurons/virology , Virus Replication/genetics
4.
Microbiol Res ; 258: 126993, 2022 May.
Article in English | MEDLINE | ID: covidwho-1693103

ABSTRACT

Pseudoviruses are viral particles coated with a heterologous envelope protein, which mediates the entry of pseudoviruses as efficiently as that of the live viruses possessing high pathogenicity and infectivity. Due to the deletion of the envelope protein gene and the absence of pathogenic genes, pseudoviruses have no autonomous replication ability and can infect host cells for only a single cycle. In addition, pseudoviruses have the desired characteristics of high safety, strong operability, and can be easily used to perform rapid throughput detection. Therefore, pseudoviruses are widely employed in the mechanistic investigation of viral infection, the screening and evaluation of monoclonal antibodies and antiviral drugs, and the detection of neutralizing antibody titers in serum after vaccination. In this review, we will discuss the construction of pseudoviruses based on different packaging systems, their current applications especially in the research of SARS-CoV-2, limitations, and further directions.


Subject(s)
COVID-19 , Vaccines , Antibodies, Neutralizing , Antiviral Agents/pharmacology , COVID-19/prevention & control , Humans , SARS-CoV-2
5.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-324142

ABSTRACT

In response to the rapid spread of the novel coronavirus, SARS-CoV-2, the U.S. has largely delegated implementation and rollback of non-pharmaceutical interventions (NPIs) to local governments on the state and county level. This asynchronous response combined with the heterogeneity of the U.S. complicates quantification of the effect of NPIs on the reproductive ratio of SARS-CoV-2 on a national level. We describe a data-driven approach to quantify the effect of NPIs that relies on county-level similarities to specialize a Bayesian mechanistic model based on observed fatalities. Using this approach, we estimate the effect of NPIs on the reproductive ratio R_t in 1,904 U.S. counties incorporating implementation, subsequent rollback, and mask mandate efficacy. We estimate that at some point before Aug 2nd, 2020, 1,808 out of the considered 1,904 U.S. counties had reduced the reproductive ratio of SARS-CoV-2 to below 1.0. However, on Aug 2nd, the reproductive ration remained below that threshold for only 702 counties. The estimated effect of any individual NPI is different across counties. Public school closings were estimated to be effective in metropolitan, urban, and suburban counties, while advisory NPIs were estimated to be effective in more rural counties. The cumulative prevalence predicted by the model ranges from 0 to 58.6% across the counties examined. The median is 2.6% while the 25th and 75th percentile are 1.3% and 44.6% respectively, indicating that most counties are far from herd immunity. Our results suggest that local conditions, including socioeconomic, demographic and infrastructural factors, in addition to the cumulative prevalence are pertinent to containment and re-opening decisions.

6.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-315634

ABSTRACT

Objectives: To investigate the CT changes of different clinical types of COVID-19 pneumonia. Methods: This retrospective study included 50 confirmed patients with COVID-19 from 16 January 2020 to 25 February 2020. We analyzed the clinical and CT characteristics of the patients between the moderate group and the severe and critical group, and the dynamic changes of severity with the CT follow-up time. Results: There were no differences in the occurrence rate of CT characteristics between the moderate group (n=34) and the severe and critical group (n=16) in the initial CT (all p >0.05). There were differences in the CT score of right lung and total CT score at the initial CT between the two groups (all p <0.05). There was a quadratic relationship between total CT score and CT follow-up time in the severe and critical group (r2=0.137, p=0.008), the total CT severity score peaked at the second follow-up CT. There was no correlation between total CT score and CT follow-up time in the moderate group (p >0.05). The total CT score of the severe and critical group was different between the initial and first follow-up, the second and third follow-ups, the third and fourth follow-ups, and the fourth and fifth follow-ups CT (all p<0.05). The total CT score of the moderate group was different between the second and third follow-ups CT (p<0.05). Conclusions: COVID-19 pneumonia with the severe and critical types progressed rapidly with the greatest severity at the second follow-up CT, and the moderate type was relatively stable.

7.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-314167

ABSTRACT

As the coronavirus disease 2019 (COVID-19) continues to be a global pandemic, policy makers have enacted and reversed non-pharmaceutical interventions with various levels of restrictions to limit its spread. Data driven approaches that analyze temporal characteristics of the pandemic and its dependence on regional conditions might supply information to support the implementation of mitigation and suppression strategies. To facilitate research in this direction on the example of the United States, we present a machine-readable dataset that aggregates relevant data from governmental, journalistic, and academic sources on the U.S. county level. In addition to county-level time-series data from the JHU CSSE COVID-19 Dashboard, our dataset contains more than 300 variables that summarize population estimates, demographics, ethnicity, housing, education, employment and income, climate, transit scores, and healthcare system-related metrics. Furthermore, we present aggregated out-of-home activity information for various points of interest for each county, including grocery stores and hospitals, summarizing data from SafeGraph and Google mobility reports. We compile information from IHME, state and county-level government, and newspapers for dates of the enactment and reversal of non-pharmaceutical interventions. By collecting these data, as well as providing tools to read them, we hope to accelerate research that investigates how the disease spreads and why spread may be different across regions. Our dataset and associated code are available at github.com/JieYingWu/COVID-19_US_County-level_Summaries.

8.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-308161

ABSTRACT

Background: The COVID-19 infection has caused 111652 deaths worldwide as of 13 April 2020. Risk factors for fatal outcomes of COVID-19 have varied across studies due to limited samples and have lacked effective qualitative and quantitative measurements. We performed a meta-analysis to evaluate risk factors for fatal outcomes of COVID-19. Methods: : Data on demographic, clinic, laboratory findings and complications were extracted. Quantitative and qualitative synthesis was conducted for weighted-mean-difference (WMD) and odds-ratio (OR) . Results: : A total of 30 studies involving 5741 survivors and 1670 deaths were included. The death cases were significantly older than survivors (WMD=15.36, 95% CI: 12.90-17.82), male and smoking history showed higher risk to develop fatal outcome (OR=3.37, 95% CI: 2.27-5.01;OR=1.37, 95% CI: 1.02-1.83, respectively). The clinical symptoms including dyspnea (OR=4.63, 95% CI: 2.85-7.54), hemoptysis (OR=3.11, 95% CI: 1.26-7.56), malaise (OR=2.44, 95% CI: 1.49-3.97). comorbidities with coronary heart disease (OR=4.36, 95% CI: 1.91-9.97), COPD (OR=3.70, 95% CI: 2.03-6.73) and cardiovascular disease (OR=3.45, 95% CI: 2.54-4.70). Compared to survivors, many laboratory indexes increased in deaths group, including serum ferritin (WMD=741.47, 95% CI: 566.77-916.16), lactate dehydrogenase (WMD=226.86, 95% CI: 177.08-276.64) and myoglobin (WMD=102.58, 95% CI: 65.12-140.04), and the decreased indexes included PaO2/FiO2 (WMD=-71.61, 95% CI: -134.11 to -9.11), platelets (WMD=-41.09, 95% CI: -47.33 to -34.85) and PaO2 (WMD=-26.09, 95% CI: -38.9 to -13.29). Main complications contributed to the fatal outcome included sepsis (OR=184.61, 95% CI: 33.43-1019.42), shock (OR=133.76, 95% CI: 36.86-485.34) and respiratory failure (OR=47.37, 95% CI: 20.65-108.66). Conclusion: The main risk factors associated with fatal outcome of COVID-19 involved male, older age, smoking history, chronic medical conditions including coronary heart disease, COPD and cardiovascular disease, clinical symptoms including dyspnea, hemoptysis and malaise, the increased laboratory indexes including serum ferritin, lactate dehydrogenase and myoglobin, the decreased indexes including PaO2/FiO2, platelets and PaO2, main complications including sepsis, shock and respiratory failure. These factors could be considered in triaging patients and allocating medical resources when such medical resources are scarce, devising improved protocols for patient diagnosis and management, and developing new drugs and other therapies to treat COVID-19 patients.

9.
Nat Commun ; 13(1): 460, 2022 01 24.
Article in English | MEDLINE | ID: covidwho-1651070

ABSTRACT

The SARS-CoV-2 Delta variant has spread rapidly worldwide. To provide data on its virological profile, we here report the first local transmission of Delta in mainland China. All 167 infections could be traced back to the first index case. Daily sequential PCR testing of quarantined individuals indicated that the viral loads of Delta infections, when they first become PCR-positive, were on average ~1000 times greater compared to lineage A/B infections during the first epidemic wave in China in early 2020, suggesting potentially faster viral replication and greater infectiousness of Delta during early infection. The estimated transmission bottleneck size of the Delta variant was generally narrow, with 1-3 virions in 29 donor-recipient transmission pairs. However, the transmission of minor iSNVs resulted in at least 3 of the 34 substitutions that were identified in the outbreak, highlighting the contribution of intra-host variants to population-level viral diversity during rapid spread.


Subject(s)
COVID-19/transmission , Contact Tracing/methods , Disease Outbreaks/prevention & control , SARS-CoV-2/isolation & purification , Animals , COVID-19/epidemiology , COVID-19/virology , Chlorocebus aethiops , Humans , RNA-Seq/methods , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2/genetics , SARS-CoV-2/physiology , Time Factors , Vero Cells , Viral Load/genetics , Viral Load/physiology , Virus Replication/genetics , Virus Replication/physiology , Virus Shedding/genetics , Virus Shedding/physiology
10.
Anal Chem ; 94(6): 2812-2819, 2022 02 15.
Article in English | MEDLINE | ID: covidwho-1607320

ABSTRACT

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has lasted for almost 2 years. Stemming its spread has posed severe challenges for clinical virus detection. A long turnaround time, complicated operation, and low accuracy have become bottlenecks in developing detection techniques. Adopting a direct antigen detection strategy, we developed a fast-responding and quantitative capacitive aptasensor for ultratrace nucleocapsid protein detection based on a low-cost microelectrode array (MEA) chip. Employing the solid-liquid interface capacitance with a sensitivity of picofarad level, the tiny change on the MEA surface can be definitively detected. As a result, the limit of detection reaches an ultralow level of femtogram per milliliter in different matrices. Integrated with efficient microfluidic enrichment, the response time of this sensor from the sample to the result is shortened to 15 s, completely meeting the real-time detection demand. Moreover, the wide linear range of the sensor is from 10-5 to 10-2 ng/mL, and a high selectivity of 6369:1 is achieved. After application and evaluation in different environmental and body fluid matrices, this sensor and the detection method have proved to be a label-free, real-time, easy-to-operate, and specific strategy for SARS-CoV-2 screening and diagnosis.


Subject(s)
COVID-19 , Coronavirus Nucleocapsid Proteins/isolation & purification , COVID-19/diagnosis , Humans , Microelectrodes , Microfluidics , Phosphoproteins/isolation & purification , SARS-CoV-2
11.
2021.
Preprint in English | Other preprints | ID: ppcovidwho-295289

ABSTRACT

Summary We report the first local transmission of the SARS-CoV-2 Delta variant in mainland China. All 167 infections could be traced back to the first index case. Daily sequential PCR testing of the quarantined subjects indicated that the viral loads of Delta infections, when they first become PCR+, were on average ∼1000 times greater compared to A/B lineage infections during initial epidemic wave in China in early 2020, suggesting potentially faster viral replication and greater infectiousness of Delta during early infection. We performed high-quality sequencing on samples from 126 individuals. Reliable epidemiological data meant that, for 111 transmission events, the donor and recipient cases were known. The estimated transmission bottleneck size was 1-3 virions with most minor intra-host single nucleotide variants (iSNVs) failing to transmit to the recipients. However, transmission heterogeneity of SARS-CoV-2 was also observed. The transmission of minor iSNVs resulted in at least 4 of the 30 substitutions identified in the outbreak, highlighting the contribution of intra-host variants to population level viral diversity during rapid spread. Disease control activities, such as the frequency of population testing, quarantine during pre-symptomatic infection, and level of virus genomic surveillance should be adjusted in order to account for the increasing prevalence of the Delta variant worldwide.

12.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-293059

ABSTRACT

Unlike SARS-CoV-1 and MERS-CoV, infection with SARS-CoV-2, the viral pathogen responsible for COVID-19, is often associated with neurologic symptoms that range from mild to severe, yet increasing evidence argues the virus does not exhibit extensive neuroinvasive properties. We demonstrate SARS-CoV-2 can infect and replicate in human iPSC-derived neurons and that infection shows limited anti-viral and inflammatory responses but increased activation of EIF2 signaling following infection as determined by RNA sequencing. Intranasal infection of K18 human ACE2 transgenic mice (K18-hACE2) with SARS-CoV-2 resulted in lung pathology associated with viral replication and immune cell infiltration. In addition, ~50% of infected mice exhibited CNS infection characterized by wide-spread viral replication in neurons accompanied by increased expression of chemokine (Cxcl9, Cxcl10, Ccl2, Ccl5 and Ccl19) and cytokine (Ifn-λ and Tnf-α) transcripts associated with microgliosis and a neuroinflammatory response consisting primarily of monocytes/macrophages. Microglia depletion via administration of colony-stimulating factor 1 receptor inhibitor, PLX5622, in SARS-CoV-2 infected mice did not affect survival or viral replication but did result in dampened expression of proinflammatory cytokine/chemokine transcripts and a reduction in monocyte/macrophage infiltration. These results argue that microglia are dispensable in terms of controlling SARS-CoV-2 replication in in the K18-hACE2 model but do contribute to an inflammatory response through expression of pro-inflammatory genes. Collectively, these findings contribute to previous work demonstrating the ability of SARS-CoV-2 to infect neurons as well as emphasizing the potential use of the K18-hACE2 model to study immunological and neuropathological aspects related to SARS-CoV-2-induced neurologic disease.

13.
Sci China Life Sci ; 2021 Oct 21.
Article in English | MEDLINE | ID: covidwho-1491326

ABSTRACT

As coronavirus disease 2019 (COVID-19) threatens human health globally, infectious disorders have become one of the most challenging problem for the medical community. Natural products (NP) have been a prolific source of antimicrobial agents with widely divergent structures and a range vast biological activities. A dataset comprising 618 articles, including 646 NP-based compounds from 672 species of natural sources with biological activities against 21 infectious pathogens from five categories, was assembled through manual selection of published articles. These data were used to identify 268 NP-based compounds classified into ten groups, which were used for network pharmacology analysis to capture the most promising lead-compounds such as agelasine D, dicumarol, dihydroartemisinin and pyridomycin. The distribution of maximum Tanimoto scores indicated that compounds which inhibited parasites exhibited low diversity, whereas the chemistries inhibiting bacteria, fungi, and viruses showed more structural diversity. A total of 331 species of medicinal plants with compounds exhibiting antimicrobial activities were selected to classify the family sources. The family Asteraceae possesses various compounds against C. neoformans, the family Anacardiaceae has compounds against Salmonella typhi, the family Cucurbitacea against the human immunodeficiency virus (HIV), and the family Ancistrocladaceae against Plasmodium. This review summarizes currently available data on NP-based antimicrobials against refractory infections to provide information for further discovery of drugs and synthetic strategies for anti-infectious agents.

14.
Parasit Vectors ; 14(1): 517, 2021 Oct 07.
Article in English | MEDLINE | ID: covidwho-1463263

ABSTRACT

BACKGROUND: Although visceral leishmaniasis (VL) was largely brought under control in most regions of China during the previous century, VL cases have rebounded in western and central China in recent decades. The aim of this study was to investigate the epidemiological features and spatial-temporal distribution of VL in mainland China from 2004 to 2019. METHODS: Incidence and mortality data for VL during the period 2004-2019 were collected from the Public Health Sciences Data Center of China and annual national epidemic reports of VL, whose data source was the National Diseases Reporting Information System. Joinpoint regression analysis was performed to explore the trends of VL. Spatial autocorrelation and spatial-temporal clustering analysis were conducted to identify the distribution and risk areas of VL transmission. RESULTS: A total of 4877 VL cases were reported in mainland China during 2004-2019, with mean annual incidence of 0.0228/100,000. VL incidence showed a decreasing trend in general during our study period (annual percentage change [APC] = -4.2564, 95% confidence interval [CI]: -8.0856 to -0.2677). Among mainly endemic provinces, VL was initially heavily epidemic in Gansu, Sichuan, and especially Xinjiang, but subsequently decreased considerably. In contrast, Shaanxi and Shanxi witnessed significantly increasing trends, especially in 2017-2019. The first-level spatial-temporal aggregation area covered two endemic provinces in northwestern China, including Gansu and Xinjiang, with the gathering time from 2004 to 2011 (relative risk [RR] = 13.91, log-likelihood ratio [LLR] = 3308.87, P < 0.001). The secondary aggregation area was detected in Shanxi province of central China, with the gathering time of 2019 (RR = 1.61, LLR = 4.88, P = 0.041). The epidemic peak of October to November disappeared in 2018-2019, leaving only one peak in March to May. CONCLUSIONS: Our findings suggest that VL is still an important endemic infectious disease in China. Epidemic trends in different provinces changed significantly and spatial-temporal aggregation areas shifted from northwestern to central China during our study period. Mitigation strategies, including large-scale screening, insecticide spraying, and health education encouraging behavioral change, in combination with other integrated approaches, are needed to decrease transmission risk in areas at risk, especially in Shanxi, Shaanxi, and Gansu provinces.


Subject(s)
Epidemics/statistics & numerical data , Epidemiological Monitoring , Leishmaniasis, Visceral/epidemiology , Public Health/statistics & numerical data , Spatio-Temporal Analysis , Adolescent , Child , Child, Preschool , China/epidemiology , Humans , Incidence , Infant , Infant, Newborn , Leishmaniasis, Visceral/mortality , Population
17.
Front Public Health ; 9: 652842, 2021.
Article in English | MEDLINE | ID: covidwho-1389255

ABSTRACT

Background: The viral shedding time (VST) of SARS-CoV-2 mainly determines its transmission and duration of infectiousness. However, it was heterogeneous in the existing studies. Here, we performed a meta-analysis to comprehensively summarize the VST of SARS-CoV-2. Methods: We searched PubMed, Web of Science, MedRxiv, BioRxiv, CNKI, CSTJ, and Wanfang up to October 25, 2020, for studies that reported VSTs of SARS-CoV-2. Pooled estimates and 95% CIs for the VSTs were calculated using log-transformed data. The VSTs in SARS-CoV-2 infections based on different demographic and clinical characteristics, treatments and specimens were stratified by subgroup analysis. Results: A total of 35 studies involving 3,385 participants met the inclusion criteria. The pooled mean VST was 16.8 days (95% CI: 14.8-19.4, I 2 = 99.56%) in SARS-CoV-2 infections. The VST was significantly longer in symptomatic infections (19.7 days, 95% CI: 17.2-22.7, I 2 = 99.34%) than in asymptomatic infections (10.9 days, 95% CI: 8.3-14.3, I 2 = 98.89%) (P < 0.05). The VST was 23.2 days (95% CI: 19.0-28.4, I 2 = 99.24%) in adults, which was significantly longer than that in children (9.9 days, 95% CI: 8.1-12.2, I 2 = 85.74%) (P < 0.05). The VST was significantly longer in persons with chronic diseases (24.2 days, 95% CI: 19.2-30.2, I 2 = 84.07%) than in those without chronic diseases (11.5 days, 95% CI: 5.3-25.0, I 2 = 82.11%) (P < 0.05). Persons receiving corticosteroid treatment (28.3 days, 95% CI: 25.6-31.2, I 2 = 0.00%) had a longer VST than those without corticosteroid treatment (16.2 days, 95% CI: 11.5-22.5, I 2 = 92.27%) (P = 0.06). The VST was significantly longer in stool specimens (30.3 days, 95% CI: 23.1-39.2, I 2 = 92.09%) than in respiratory tract specimens (17.5 days, 95% CI: 14.9-20.6, I 2 = 99.67%) (P < 0.05). Conclusions: A longer VST was found in symptomatic infections, infected adults, persons with chronic diseases, and stool specimens.


Subject(s)
COVID-19/virology , SARS-CoV-2/physiology , Virus Shedding , Adrenal Cortex Hormones/therapeutic use , Adult , Asymptomatic Infections , Child , Comorbidity , Feces/virology , Humans
18.
Drugs and Clinic ; 35(4):614-619, 2020.
Article in Chinese | GIM | ID: covidwho-1374634

ABSTRACT

To improve the rationality and safety of anti-novel coronavirus drugs in patients with corona Virus disease 2019 (COVID-19), especially those with underlying diseases. Based on antiviral drugs mentioned in "COVID-19 Treatment Plan (Trial Version 7)", the clinical pharmacokinetic characteristics, drug interaction and adverse reaction information of these antiviral drugs were summarized by consulting the literature, collecting the information from the antiviral drugs instructions and the information from MCDEX rational drug use system. And the reasonable suggestions for drug monitoring were summarized and put forward. From the perspective of pharmacokinetics and drug interaction, the monitoring of antiviral drugs and combined drugs in patients with COVID-19 should be strengthened, which will be helpful for safe and rational use of these drugs.

19.
Infect Drug Resist ; 14: 3169-3174, 2021.
Article in English | MEDLINE | ID: covidwho-1372034

ABSTRACT

PURPOSE: To cope with the SARS-CoV-2 epidemic, several rapid nucleic acid assays have been approved for use, but the analytical performance has not been well evaluated. In this report, two key performance parameters, analytical sensitivity (limit of detection) and reproducibility, of three approved rapid nucleic acid assays were assessed using heat-inactivated SARS-CoV-2 culture supernatants quantified by digital PCR. METHODS: The LOD (limit of detection) and reproducibility of three approved rapid nucleic acid assays using their own instruments were assessed, while the LOD and reproducibility of two assays on a 7500 Real-Time instrument were assessed at the same time. RESULTS: Using their own instruments, 100% of samples with 1150 copies/mL viral RNA could be detected by the Da An and Coyote assays, while 90% of samples could be detected by the Ustar assay; yet, for 525 copies/mL and 287.5 copies/mL viral RNA, the detection rate of the Ustar assay was higher than that of either the Da An or Coyote assays. However, the three assays did not produce statistically significant results with the three different concentrations of viral RNA (P=0.46, 0.46 and 0.46). Using a 7500 Real-Time instrument, Da An and Coyote assays did not produce statistically significant results with the 1150, 525 and 287.5 copies/mL viral RNA (P>0.99, >0.99 and >0.99). The positive and negative detection rates of the three assays in the intra- and inter-assay stages were 100% on both their own instruments and the 7500 real-time PCR instrument. CONCLUSION: Positive or strongly positive samples can be detected by the rapid nucleic acid assay, but the analytical performance should be optimized, and comprehensive evaluations are also required.

20.
Int J Infect Dis ; 111: 5-9, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1351714

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the infectiousness of re-positive coronavirus disease 2019 (COVID-19) patients. METHODS: All nucleic acid testing (NAT) was performed using throat swabs, nasopharyngeal swabs, and anal swabs, which were tested by Fluorescent quantitative realtime PCR. Re-positive cases were defined as a discharged patient who re-tested positive by NAT. Micro-neutralization of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was performed based on the methods for severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) viruses. IgM and IgG against the N protein of SARS-CoV-2 were determined by ELISA. RESULTS: A total 255 (16.04%) of 1590 COVID-19 patients were re-positive. The re-positive cases were more likely to occur in patients in the 20-39 years age group and in patients with disease of moderate severity. Quantitative PCR showed that cycle threshold (Ct) values and viral loads were both far lower than in the hospitalized COVID-19 patients. The viral load in re-positive cases was very low. Viral culture of the samples from re-positive patients showed no cytopathic effect, and NAT of the culture medium of viral cultures all exhibited negative results. CONCLUSION: The viral load in re-positive cases was very low; patients were not infectious and the risk of human-to-human transmission was extremely low. Discharged COVID-19 patients should undergo home health management for 3 weeks.


Subject(s)
COVID-19 , Humans , Real-Time Polymerase Chain Reaction , SARS-CoV-2 , Serologic Tests , Viral Load
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