Highlighted Prospects of an IgM/IgG Antibodies Test in Identifying Individuals With Asymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection

Context.— Covert severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections could be seeding new outbreaks. How to identify asymptomatic SARS-CoV-2 infections early has become a global focus. Objective.— To explore the roles of immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies detection, nucleic acid tests, and computed tomography (CT) scanning to identify asymptomatic SARS-CoV-2 infection. Design.— The clinical data of 389 individuals with close contacts, including in general characteristics, SARS-CoV-2 etiology, serum-specific IgM and IgG antibody detection and CT imaging results, were systematically analyzed. Results.— The present study showed that only 89 of 389 individuals with close contacts were positive after the first nucleic acid test, while 300 individuals were still negative after 2 nucleic acid tests. Among the 300 individuals, 75 did not have pneumonia, and the other 225 individuals had pulmonary imaging changes. A total of 143 individuals were eventually diagnosed as having asymptomatic infection through IgM antibody and IgG antibody detection. The sensitivity, specificity, and false-negative rate of IgM and IgG antibody detection were approximately 97.1% (347 of 357), 95.3% (204 of 214), and 4.67% (10 of 214), respectively. It also indicated that during approximately 2 weeks, most individuals were both IgM positive and IgG positive, accounting for 68.57% (72 of 105). During approximately 3 weeks, the proportion of IgM-positive and IgG-positive individuals decreased to 8.57% (9 of 105), and the proportion of IgM-negative and IgG-positive individuals increased to 76.19% (80 of 105). Conclusions.— There are highlighted prospects of IgM/IgG antibody detection as a preferred method in identifying the individuals with asymptomatic SARS-CoV-2 infection, especially combined with nucleic acid tests and pulmonary CT scanning.

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Optimize Clinical Laboratory Diagnosis of COVID-19 from Suspect Cases by Likelihood Ratio of SARS-CoV-2 IgM and IgG antibody

10.1101/2020.04.07.20053660 ◽

2020 ◽

Cited By ~ 1

Author(s):

Feng Yangchun

Keyword(s):

Nucleic Acid ◽

Likelihood Ratio ◽

Posterior Probability ◽

Clinical Laboratory ◽

Laboratory Diagnosis ◽

Antibody Detection ◽

Nucleic Acid Detection ◽

Igg Antibodies ◽

Igg Antibody ◽

Antibody Tests

ObjectiveTo optimize clinical laboratory diagnosis of COVID-19 from suspect cases by Likelihood Ratio of SARS-CoV-2 IgM and IgG antibody.MethodsBy reinterpreting the data in the article “Diagnostic Value of Combined Detection of Serum 2019 novel coronavirus IgM and IgG Antibodies in novel coronavirusin Infection”, the positive likelihood ratio of IgM and IgG antibody in diagnosis of COVID-19 (nucleic acid positive patients) was calculated, and the posterior probability of IgM and IgG antibodies and their tandem detection to diagnose was finally calculated.ResultsThe positive likelihood ratios of single IgM and IgG antibody were 18.50 and 12.65 respectively, and the posterior probabilities were 90.18% and 86.26% respectively. However, the posterior probability of the two antibodies tandem detection is 99.15%, which can give clinicians quantitative confidence in the diagnosis of COVID-19 from suspected cases. According to the results of this study, combining the advantages and disadvantages of nucleic acid detection and antibody detection, the clinical pathway for clinicians to diagnose COVID-19 is found.ConclusionFor suspected cases, IgM and IgG antibody tests should be firstly done at the same time. If the antibody tests are all positive, COVID-19 can be confirmed. If not, nucleic acid detection (one or more times) is performed, and in extreme cases, high-throughput viral genome sequencing is performed.

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Serological detection of 2019-nCoV respond to the epidemic: A useful complement to nucleic acid testing

10.1101/2020.03.04.20030916 ◽

2020 ◽

Cited By ~ 12

Author(s):

Jin Zhang ◽

Jianhua Liu ◽

Na Li ◽

Yong Liu ◽

Rui Ye ◽

...

Keyword(s):

Nucleic Acid ◽

Virus Disease ◽

Roc Curves ◽

Laboratory Diagnosis ◽

Healthy People ◽

Antibody Detection ◽

Nucleic Acid Detection ◽

Igg Antibodies ◽

Igg Antibody ◽

Epidemic Area

AbstractBackgroundPneumonia caused by 2019 novel coronavirus (2019-nCoV) was first reported in Wuhan, Hubei Province, China in December 2019. Then it has been reported in more than 20 countries and regions overseas rapidly. More than eighty thousand cases have been infected, resulting in more than three thousand deaths. Due to the limitation of nucleic acid detection, many clinical suspected cases cannot be diagnosed in time.MethodsWe used automated chemiluminescent immunoassay to detect serum IgM and IgG antibodies to 2019-nCoV of 736 subjects including confirmed Corona Virus Disease 2019 (COVID-19) patients, non-COVID-19 fever patients, other disease patients and medical staff as well as healthy people. The dynamic process of antibody production in COVID-19 disease progression were analyzed, and the value of antibody detection in the laboratory diagnosis of COVID-19 were evaluated.ResultsCOVID-19 patients were becoming reactive(positive) for specific anti-2019-nCoV IgM antibodies from 7-12 days after the onset of morbidity, followed closely by the IgG. The levels of specific IgM and IgG antibodies increased with the progression of the disease. The trend of IgM and IgG changes in different cases is not exactly the same. The levels of IgM and IgG and their distributions in different groups were different with that of healthy people. The areas under the ROC curves for IgM and IgG to diagnose COVID-19 were 0.988 and 1.000, respectively.ConclusionsSpecific IgM or IgG antibody detection had good sensitivity and specificity for the diagnosis of suspected fever cases. Detection of specific antibodies in patients with fever can be a good distinction between COVID-19 and other diseases in low epidemic area.

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The positive rate of IgM and IgG antibodies against SARS-CoV-2 is similar in severe and non-severe COVID-19 patients

Revista Romana de Medicina de Laborator ◽

10.2478/rrlm-2021-0010 ◽

2021 ◽

Vol 29 (1) ◽

pp. 85-91

Author(s):

Nan Jiang ◽

Yaoyao Sun ◽

Hongyan Sun ◽

Bo Yang ◽

Juan Tan ◽

...

Keyword(s):

Nucleic Acid ◽

Diagnostic Method ◽

Effective Means ◽

Antibody Detection ◽

Igg Antibodies ◽

Igg Antibody ◽

Nucleic Acid Test ◽

Positive Rate ◽

Antibody Levels ◽

Acid Test

Abstract Background: Coronavirus disease 2019 (COVID-19) has spread rapidly in China and globally. In order to control the spread of the epidemic, it is important to find an efficient diagnostic method. Objectives: The aim of this study was to assess the responses of antibodies during SARS-CoV-2 infection in relation to disease severity and to evaluate the association between the positive rate of antibody detection and nucleic acid test. Methods: Ninety patients with SARS-CoV-2 infection were recruited in this retrospective observational study. Demographic, clinical data, and SARS-CoV-2 IgM and IgG antibodies in serum specimens were detected at 4 and 6 weeks after diagnosis. Results: IgM and IgG antibody levels showed a decreased tendency, the titers at week 4 were higher than the titers at week 6: The positive rates of IgM at week 4 and 6 were 92.9% and 67.9%, respectively. The positive rates of IgG at week 4 and week 6 were 100%. No association was found between the positive rate of antibody detection at week 4 or 6 and that of nucleic acid test (P>0.05). No difference between the positive rate of antibodies against SARS-CoV-2 in severe and non-severe COVID-19 patients was observed. Conclusions: Antibody detection is an effective means in the diagnosis of COVID-19. The titer and positive rate of IgM are lower than those of IgG in the first six weeks after infection. Positive rate of antibodies was not different between severe and non-severe patients.

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Antibody Detection and Dynamic Characteristics in Patients With Coronavirus Disease 2019

Clinical Infectious Diseases ◽

10.1093/cid/ciaa461 ◽

2020 ◽

Vol 71 (8) ◽

pp. 1930-1934 ◽

Cited By ~ 108

Author(s):

Fei Xiang ◽

Xiaorong Wang ◽

Xinliang He ◽

Zhenghong Peng ◽

Bohan Yang ◽

...

Keyword(s):

Nucleic Acid ◽

Symptom Onset ◽

Predictive Value ◽

Immunoglobulin M ◽

Antibody Detection ◽

Enzyme Linked Immunosorbent Assay ◽

Igg Antibodies ◽

Great Specificity ◽

Sensitivity Specificity ◽

Consistency Rate

Abstract Background The coronavirus disease 2019 (COVID-19), caused by infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been rapidly spreading nationwide and abroad. A serologic test to identify antibody dynamics and response to SARS-CoV-2 was developed. Methods The antibodies against SARS-CoV-2 were detected by an enzyme-linked immunosorbent assay based on the recombinant nucleocapsid protein of SARS-CoV-2 in patients with confirmed or suspected COVID-19 at 3–40 days after symptom onset. The gold standard for COVID-19 diagnosis was nucleic acid testing for SARS-CoV-2 by real-time reverse-transcription polymerase chain reaction (rRT-PCR). The serodiagnostic power of the specific immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies against SARS-CoV-2 was investigated in terms of sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and consistency rate. Results The seroconversion of specific IgM and IgG antibodies were observed as early as the fourth day after symptom onset. In the patients with confirmed COVID-19, sensitivity, specificity, PPV, NPV, and consistency rate of IgM were 77.3% (51/66), 100%, 100%, 80.0%, and 88.1%, respectively, and those of IgG were 83.3% (55/66), 95.0%, 94.8%, 83.8%, and 88.9%. In patients with suspected COVID-19, sensitivity, specificity, PPV, NPV, and consistency rate of IgM were 87.5% (21/24), 100%, 100%, 95.2%, and 96.4%, respectively, and those of IgG were 70.8% (17/24), 96.6%, 85.0%, 89.1%, and 88.1%. Both antibodies performed well in serodiagnosis for COVID-19 and rely on great specificity. Conclusions The antibodies against SARS-CoV-2 can be detected in the middle and later stages of the illness. Antibody detection may play an important role in the diagnosis of COVID-19 as a complementary approach to viral nucleic acid assays.

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Are RNA-Based Tests Sufficient for COVID-19 Diagnosis? An Inspiration of Three Asymptomatic Cases

Cell Transplantation ◽

10.1177/0963689720985453 ◽

2021 ◽

Vol 30 ◽

pp. 096368972098545

Author(s):

Tao Hu ◽

Xiao Liu ◽

Qinan Yin ◽

Xingting Duan ◽

Li Yan

Keyword(s):

Computed Tomography ◽

Nucleic Acid ◽

Virus Infection ◽

Severe Acute Respiratory Syndrome ◽

The Other ◽

Computed Tomography Scan ◽

Health Authorities ◽

History Of ◽

Tomography Scan ◽

Nucleic Acid Tests

In this work, we discovered a new phenomenon—asymptomatic COVID-19 infection, or covert case, during the pandemic. All the 3 patients had a history of exposure, with no symptoms, and no abnormalities were found in computed tomography scan or lab tests. Except for case 2, the other patients’ severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) nucleic acid tests were negative. But their anti-SARS-COV-2 nucleocapsid antibody showed a dynamic trend, consistent with the process of virus infection and clearance. A growing number of asymptomatic or covert cases need more attention. Lack of surveillance may lead to another outbreak. We hope to demonstrate our cases to attract the attention of governments or health authorities that covert cases should be the focus as well.

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Efficacy and Safety of Lianhuaqingwen Capsules for the Prevention of Coronavirus Disease 2019: A Prospective Open-Label Controlled Trial

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2021/7962630 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Xiaowei Gong ◽

Boyun Yuan ◽

Yadong Yuan ◽

Fengju Li

Keyword(s):

Nucleic Acid ◽

Treatment Group ◽

Close Contact ◽

Controlled Trial ◽

Control Group ◽

Open Label ◽

Medical Observation ◽

Observation Period ◽

Close Contacts ◽

Nucleic Acid Tests

Coronavirus disease 2019 (COVID-19) has become a global pandemic. Community and close contact exposures continue to drive the COVID-19 pandemic. There is no confirmed effective treatment for suspected cases and close contacts. Lianhuaqingwen (LH) capsules, a repurposed Chinese herbal product that is currently on the market, have proven effective for influenza and COVID-19. To determine the safety and efficacy of LH capsules for the prevention of COVID-19, we conducted a prospective open-label controlled trial of LH capsules on subjects who had close contact with people infected with COVID-19. Subjects received LH capsules (4 capsules, three times daily) or the usual medical observation for 14 days. The primary endpoint was the rate of positive nucleic acid tests of nasal and pharyngeal swabs during the quarantine medical observation period. We included 1976 patients, including 1101 in the treatment group and 875 in the control group. The rate of positive nucleic acid tests in the treatment group was significantly lower than that in the control group (0.27% vs. 1.14%, respectively; mean difference: −0.87%; 95% CI: −1.83 to −0.13; p = 0.0174 ) during the quarantine medical observation period (14 days). Among subjects with different close contact states, there was no significant difference in the rate of positive nucleic acid test results among close contacts in the treatment group and the control group (6.45% vs. 11.43%, respectively; p = 0.6762 ). Among secondary close contacts, the rate of positive nucleic acid tests in the treatment group was significantly lower than that in the control group (0.09% vs. 0.71%, respectively; p = 0.0485 ). No serious adverse events were reported. Taken together, and in light of the safety and effectiveness profiles, these results show that LH capsules can be considered to prevent the progression of COVID-19 after close contact with an infected person. This trial is registered with ChiCTR2100043012.

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Development of Dual Fluorescent Microsphere Immunological Assay for Detection of Pseudorabies Virus gE and gB IgG Antibodies

10.21203/rs.3.rs-24925/v1 ◽

2020 ◽

Author(s):

chihai ji ◽

Jingyu Wang ◽

Yuchen Zeng ◽

Haoming Pan ◽

Yingfang Wei ◽

...

Keyword(s):

Pseudorabies Virus ◽

High Specificity ◽

Antibody Detection ◽

Economic Losses ◽

Igg Antibodies ◽

Wild Type ◽

Swine Industry ◽

Igg Antibody ◽

Fluorescent Microsphere ◽

Specificity And Sensitivity

Abstract Background Pseudorabies, also known as Aujezsky’s disease, is an acute viral infection caused by pseudorabies virus (PRV). Swine are one of the natural hosts of pseudorabies, therefore, the disease brings huge economic losses to the swine industry. Establishment of a differential diagnosis technique that can distinguish between wild-type infected and vaccinated pigs, and monitor vaccine-induced IgG is crucial for eventual eradication of pseudorabies.Results The aim of this study was to develop a rapid dual detection method for PRV gE and gB protein IgG antibodies with high specificity and sensitivity. PRV gE codons at amino acid residues (aa) 52–238 and gB codons at aa 539–741 were expressed to obtain recombinant PRV gE and gB proteins by pMAL-c5x vector. After purification with Qiagen Ni–NTA agarose affinity, the two proteins were analyzed by SDS-PAGE and immunoblotting assay. Two single fluorescent-microsphere immunoassays (FMIA) were established by coupling two recombinant proteins (gE and gB) with two magnetic microbeads and an effective dual FMIA was developed by integrating the two single assays. Optimal serum dilution for each assay, correlation with other common swine virus-positive sera and comparison with ELISA for two PRV antigens were tested for validation. Compared with ELISA, the specificity and sensitivity were 99.26% and 92.3% for gE IgG antibody detection and 95.74% and 96.3% for gB IgG antibody detection by dual-FMIA.Conclusion We provide a new method for monitoring PRV protective antibody in vaccinated pigs and differentiating wild-type-PRV-infected from vaccinated pigs

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A Perspective on Re-Detectable Positive SARS-CoV-2 Nucleic Acid Results in Recovered COVID-19 Patients

Disaster Medicine and Public Health Preparedness ◽

10.1017/dmp.2020.392 ◽

2020 ◽

pp. 1-5

Author(s):

Yanfei He ◽

Yu-Chao Dong

Keyword(s):

Nucleic Acid ◽

Animal Experiments ◽

Patient Discharge ◽

Clinical Work ◽

Igg Antibody ◽

Viral Virulence ◽

And Control ◽

Nucleic Acid Tests

ABSTRACT Objectives: There have been reports on re-detectable positive nucleic acid tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in recovered coronavirus disease (COVID-19) patients. In this study, we look at the clinical characteristics, possible causes, pathogenesis, and infectivity of re-detectable positive patients and provide up-to-date information to public health policy planners and clinicians. Methods: By consulting the latest research data and related progress data of re-detectable positive patients, this study addresses the implications that this special group brings to clinical work and disease prevention and control. Results: We discuss in detail the phenomenon of re-detectable positive nucleic acid tests for recovered patients. There are many possible causes of a re-detectable positive, but there is no 1 factor that can fully explain this phenomenon. Conclusions: It can’t be completely ruled out that the re-detectable positive patients are infectious. We should be alert to these re-detectable positive patients becoming chronic virus carriers, and virus serological IgM and IgG antibody tests should be added before patient discharge. It is urgent to find a more powerful evidence-based and virological basis for the integrity of viral ribonucleic acid and the variation of viral virulence with time through cell experiments in vitro and animal experiments in vivo.

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Longitudinal Change of Severe Acute Respiratory Syndrome Coronavirus 2 Antibodies in Patients with Coronavirus Disease 2019

The Journal of Infectious Diseases ◽

10.1093/infdis/jiaa229 ◽

2020 ◽

Vol 222 (2) ◽

pp. 183-188 ◽

Cited By ~ 38

Author(s):

Guoxin Zhang ◽

Shuke Nie ◽

Zhaohui Zhang ◽

Zhentao Zhang

Keyword(s):

Severe Acute Respiratory Syndrome ◽

Disease Onset ◽

Immunoglobulin M ◽

Longitudinal Change ◽

Igg Antibody ◽

Serological Tests ◽

Significant Difference ◽

Rapid Spread ◽

Novel Coronavirus ◽

Acid Test

Abstract Background A novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has recently emerged and caused the rapid spread of coronavirus disease 2019 (COVID-19) worldwide. Methods We did a retrospective study and included COVID-19 patients admitted to Renmin Hospital of Wuhan University between 1 February and 29 February 2020. Antibody assay was conducted to detect COVID-19 envelope protein E and nucleocapsid protein N antigen. Results One hundred twelve patients were recruited with symptoms of fever, cough, fatigue, myalgia, and diarrhea. All patients underwent antibody tests. Fifty-eight (51.79%) were positive for both immunoglobulin M (IgM) and immunoglobulin G (IgG), 7 (6.25%) were negative for both antibodies, 1 (0.89%) was positive for only IgM, and 46 (41.07%) were positive for only IgG. IgM antibody appeared within a week post–disease onset, lasted for 1 month, and gradually decreased, whereas IgG antibody was produced 10 days after infection and lasted for a longer time. However, no significant difference in levels of IgM and IgG antibodies between positive and negative patients of nucleic acid test after treatment was found. Conclusions Our results indicate that serological tests could be a powerful approach for the early diagnosis of COVID-19.

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Comparison of three anti-coccidioides antibody enzyme immunoassay kits for the diagnosis of coccidioidomycosis

Medical Mycology ◽

10.1093/mmy/myz125 ◽

2020 ◽

Vol 58 (6) ◽

pp. 774-778 ◽

Cited By ~ 1

Author(s):

Joshua Malo ◽

Eric Holbrook ◽

Tirdad Zangeneh ◽

Chris Strawter ◽

Eyal Oren ◽

...

Keyword(s):

Enzyme Immunoassay ◽

Diagnostic Testing ◽

High Risk Patient ◽

Immunoglobulin M ◽

Antibody Detection ◽

Serum Samples ◽

Igg Antibody ◽

Igm Antibodies ◽

Igm Antibody ◽

Detection Specificity

Abstract Coccidioidomycosis is a common cause of community-acquired pneumonia in endemic areas of the southwestern United States. Clinical presentations range from self-limited disease to severe, disseminated disease. As such, early and accurate diagnosis is essential to ensure appropriate treatment and monitoring. Currently available diagnostic testing has variable accuracy, particularly in certain patient populations, and new tests may offer improved accuracy for the diagnosis of coccidioidomycosis. Serum samples from patients with coccidioidomycosis and controls were tested for immunoglobulin G (IgG) and immunoglobulin M (IgM) antibodies using the MVista Coccidioides antibody detection EIA and two commonly used commercial enzyme immunoassay (EIA) kits: the IMMY Omega EIA and the Meridian Premier EIA. The sensitivity of the IgG antibody detection was 87.4% using the MVista test compared to 46.6% for IMMY and 70.9% for Meridian. The sensitivity for IgM antibody detection was 61.2% for the MVista test, 22.3% for IMMY and 29.1% for Meridian. For IgG antibody detection, specificity was 90% for the MVista EIA, 94.6% for IMMY, 96.4% for Meridian. For IgM antibody detection, specificity was 95.3% for the MVista test 98.2% for IMMY and 99.1% for Meridian. The MVista Coccidioides antibody EIA offers improved sensitivity, including among high-risk patient populations, for the detection of IgG and IgM antibodies in comparison to other currently available EIAs.

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