Seroprevalence of Antibodies to SARS-CoV-2 in Guangdong Province, China between March to June 2020

Guangdong province, located in South China, is an important economic hub with a large domestic migrant population and was among the earliest areas to report COVID-19 cases outside of Wuhan. We conducted a cross-sectional, age-stratified serosurvey to determine the seroprevalence of antibodies against SARS-CoV-2 after the emergence of COVID-19 in Guangdong. We tested 14,629 residual serum samples that were submitted for clinical testing from 21 prefectures between March and June 2020 for SARS-CoV-2 antibodies using a magnetic particle based chemiluminescent enzyme immunoassay and validated the results using a pseudovirus neutralization assay. We found 21 samples positive for SARS-CoV-2 IgG, resulting in an estimated age- and sex-weighted seroprevalence of 0.15% (95% CI: 0.06–0.24%). The overall age-specific seroprevalence was 0.07% (95% CI: 0.01–0.24%) in persons up to 9 years old, 0.22% (95% CI: 0.03–0.79%) in persons aged 10–19, 0.16% (95% CI: 0.07–0.33%) in persons aged 20–39, 0.13% (95% CI: 0.03–0.33%) in persons aged 40–59 and 0.18% (95% CI: 0.07–0.40%) in persons ≥60 years old. Fourteen (67%) samples had pseudovirus neutralization titers to S-protein, suggesting most of the IgG-positive samples were true-positives. Seroprevalence of antibodies to SARS-CoV-2 was low, indicating that there were no hidden epidemics during this period. Vaccination is urgently needed to increase population immunity to SARS-CoV-2.

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Presence of Antibodies against Sindbis Virus in the Israeli Population: A Nationwide Cross-Sectional Study

Viruses ◽

10.3390/v11060542 ◽

2019 ◽

Vol 11 (6) ◽

pp. 542

Author(s):

Ravit Koren ◽

Ravit Bassal ◽

Tamy Shohat ◽

Daniel Cohen ◽

Orna Mor ◽

...

Keyword(s):

Sindbis Virus ◽

Metropolitan Areas ◽

Multivariable Analysis ◽

Neutralization Assay ◽

Cross Sectional Study ◽

Older Age ◽

Igg Antibodies ◽

Serum Samples ◽

Cross Sectional ◽

Israeli Population

Sindbis virus (SINV) is a mosquito-borne alphavirus circulating globally. SINV outbreaks have been mainly reported in North-European countries. In Israel, SINV was detected in 6.3% of mosquito pools; however, SINV infection in humans has rarely been diagnosed. A serologic survey to detect SINV IgG antibodies was conducted to evaluate the seroprevalence of SINV in the Israeli population. In total, 3145 serum samples collected in 2011–2014, representing all age and population groups in Israel, were assessed using an indirect ELISA assay, and a neutralization assay was performed on all ELISA-positive samples. The prevalence rates of SINV IgG antibodies were calculated. Logistic regressions models were applied to assess the association between demographic characteristics and SINV seropositivity. Overall, 113 (3.6%) and 59 (1.9%) samples were positive for ELISA and neutralization SINV IgG, respectively. Multivariable analysis demonstrated that SINV seropositivity was significantly associated with older age and residence outside metropolitan areas. These results demonstrate that, despite no outbreaks or clinical presentation, SINV infects the human population in Israel. Seropositivity is countrywide, more frequent in people of older age, and less diffuse in Israel’s metropolitan areas. Seroprevalence studies from other countries will add to our understanding of the global burden of SINV and the risk for potential SINV outbreaks.

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Seroprevalence of novel coronavirus disease (COVID-19) in Kobe, Japan

10.1101/2020.04.26.20079822 ◽

2020 ◽

Cited By ~ 25

Author(s):

Asako Doi ◽

Kentaro Iwata ◽

Hirokazu Kuroda ◽

Toshikazu Hasuike ◽

Seiko Nasu ◽

...

Keyword(s):

Cross Sectional Study ◽

Serological Study ◽

Serum Samples ◽

Cross Sectional ◽

City Population ◽

Novel Coronavirus ◽

Outpatient Settings ◽

Developed Nations ◽

Kobe City ◽

Age And Sex

AbstractBackgroundCoronavirus disease 2019 (COVID-19) pandemic caused by SARS-CoV-2 has been affecting many people on earth and our society. Japan is known to have relatively less number of infections as well as deaths among developed nations. However, accurate prevalence of COVID-19 in Japan remains unknown. Therefore, we conducted a cross-sectional study to estimate seroprevalence of SARS-CoV-2 infection.MethodsWe conducted a cross-sectional serologic testing for SARS-CoV-2 antibody using 1,000 samples from patients at outpatient settings who visited the clinic from March 31 to April 7, 2020, stratified by the decade of age and sex.ResultsThere were 33 positive IgG among 1,000 serum samples (3.3%, 95%CI: 2.3-4.6%). By applying this figure to the census of Kobe City (population: 1,518,870), it is estimated that the number of people with positive IgG be 50,123 (95%CI: 34,934-69,868). Age and sex adjusted prevalence of positivity was calculated 2.7% (95%CI: 1.8-3.9%), and the estimated number of people with positive IgG was 40,999 (95%CI: 27,333-59,221). These numbers were 396 to 858 fold more than confirmed cases with PCR testing in Kobe City.ConclusionsOur cross-sectional serological study suggests that the number of people with seropositive for SARS-CoV-2 infection in Kobe, Japan is far more than the confirmed cases by PCR testing.

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Soluble CD163 as a Potential Biomarker in Systemic Sclerosis

Disease Markers ◽

10.1155/2018/8509583 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 10

Author(s):

Camelia Frantz ◽

Sonia Pezet ◽

Jerome Avouac ◽

Yannick Allanore

Keyword(s):

Systemic Sclerosis ◽

Clinical Laboratory ◽

Control Group ◽

Signaling System ◽

Serum Samples ◽

Cross Sectional ◽

Potential Biomarker ◽

Significant Difference ◽

Urine And Serum ◽

Age And Sex

Objective. To evaluate the performance of serum and urinary sCD163 concentrations as possible biomarker in systemic sclerosis (SSc). Methods. Urine and serum samples were obtained from SSc patients and age- and sex-matched controls. Serum and urinary sCD163 concentrations were measured by commercially available ELISA kit. SSc patients were assessed following international guidelines. Cross-sectional analyses were performed. Results. Two hundred and three SSc patients were included. The control group consisted of 47 age- and sex-matched patients having noninflammatory diseases, mainly osteoporosis. Serum sCD163 levels were significantly higher in SSc patients compared with controls (mean ± SD: 529 ± 251 versus 385 ± 153 ng/mL; p<0.001). Urinary sCD163 concentrations were higher in SSc patients than controls, but this did not reach significance (236 ± 498 versus 176 ± 173 ng/mg uCr; p=0.580). The sCD163 concentrations were not associated with clinical, laboratory, and instrumental characteristics of SSc patients. Conclusion. To our knowledge, this is the first evaluation of both serum and urinary sCD163 levels in SSc. Our results show a significant difference for sera values that should be prioritized for further studies as compared to urinary measurements. Our results further support that the M2 macrophages/CD163 signaling system may play a role in the pathogenesis of SSc, although we could not identify a subset of SSc patients with higher concentrations.

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DISAPPEARANCE OF ANTIBODIES IN COVID-19 MYTHS ORREALITY

Pakistan Armed Forces Medical Journal ◽

10.51253/pafmj.v1i1.7940 ◽

2021 ◽

Vol 71 (Suppl-3) ◽

pp. S530-33

Author(s):

Maqbool Raza ◽

Muhammed Ali Raza ◽

De Emmal Asjad Cheema ◽

Maham Asjad Cheema ◽

Atif Rafique ◽

...

Keyword(s):

Antibody Level ◽

Neutralizing Antibodies ◽

Neutralizing Antibody ◽

Neutralization Assay ◽

Cross Sectional Study ◽

Assay Method ◽

Military Hospital ◽

Serum Samples ◽

Cross Sectional ◽

Severity Of The Disease

Objective: To explore the disappearance of neutralizing antibodies from patients, their myths, and facts. Study Design: Cross-sectional study. Place and Duration of Study: Combined Military Hospital Multan Pakistan, from Jul 2021 to Aug 2021. Methodology: A total of 100 blood samples were collected from 100 COVID-19 patients. These 100 patients were followed up for a period of 3 months. Antibodies were determined with the modified neutralization assay method and enzyme-linked immuno-sorbent assay (ELISA). Results: The antibody level by NA and ELISA peaked on days 30-35 then decreased slightly. In multivariate analysis, patients aged 25-35, 36-56, and 57-84 years had a higher neutralizing antibody level than those aged 10-21 years. The patient with the worst clinical manifestation had a higher neutralizing antibody titer. In serum samples, IgG was undetectable at 18.3% and 11% and the geographical mean reciprocal titers dropped from 244 at 3-month period and neutralizing antibodies, the geographical mean reciprocal titers dropped from 874 at 3 months. Conclusion: All COVID-19 patients were seropositive and significantly neutralizing antibody response. Neutralizing antibody levels depend on the time after the onset of symptoms, age, and severity of the disease.

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Evaluation of Serum Calprotectin Level and Disease Activity in Patients with Rheumatoid Arthritis

Current Rheumatology Reviews ◽

10.2174/1573397115666190122113221 ◽

2019 ◽

Vol 15 (4) ◽

pp. 316-320

Author(s):

Mir Amir Aghdashi ◽

Seyedmostafa Seyedmardani ◽

Sholeh Ghasemi ◽

Zohre Khodamoradi

Keyword(s):

Rheumatoid Arthritis ◽

Disease Activity ◽

Inflammatory Arthritis ◽

Unknown Etiology ◽

Tender Joint Count ◽

Serum Samples ◽

Tender Joint ◽

Cross Sectional ◽

Calprotectin Level ◽

Remission Phase

Background: Rheumatoid Arthritis (RA) is the most common type of chronic inflammatory arthritis with unknown etiology marked by a symmetric, peripheral polyarthritis. Calprotectin also can be used as a biomarker of disease activity in inflammatory arthritis and other autoimmune diseases. Objective: In this study, we evaluated the association between serum calprotectin level and severity of RA activity. Methods: A cross-sectional study was conducted on 44 RA patients with disease flare-up. Serum samples were obtained from all patients to measure calprotectin, ESR, CRP prior to starting the treatment and after treatment period in the remission phase. Based on Disease Activity Score 28 (DAS28), disease activity was calculated. Results: Of 44 RA patients, 9(20.5%) were male and 35(79.5%) were female. The mean age of our cases was 53±1.6 years. Seventeen (38.6%) patients had moderate DAS28 and 27(61.4%) had high DAS28. The average level of calprotectin in the flare-up phase was 347.12±203.60 ng/ml and 188.04±23.58 ng/ml in the remission phase. We did not find any significant association between calprotectin and tender joint count (TJC; P=0.22), swollen joint count (SJC; P=0.87), and general health (GH; P=0.59), whereas significant associations were found between the calprotectin level and ESR (p=0.001) and DAS28 (p=0.02). The average calprotectin level in moderate DAS28 (275.21±217.96 ng/ml) was significantly lower than that in high DAS28 (392.4±183.88 ng/ml) (p=0.05). Conclusion: We showed that the serum level of calprotectin can be a useful and reliable biomarker in RA activity and its severity. It also can predict treatment response.

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Age- and sex-specific profiles of temporal fasting plasma glucose variability in a population undergoing routine health screening

BMC Public Health ◽

10.1186/s12889-021-10367-x ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Agyei Helena Lartey ◽

Xiaona Li ◽

Zhongqi Li ◽

Qun Zhang ◽

Jianming Wang

Keyword(s):

Plasma Glucose ◽

Fasting Plasma Glucose ◽

Chinese Population ◽

Age Groups ◽

Health Screening ◽

Health Examination ◽

Cross Sectional ◽

Fasting Plasma ◽

Percentage Difference ◽

Age And Sex

Abstract Background Fasting plasma glucose (FPG) variability is a significant predictor of mortality, especially in patients with poor glycemic control. This study aimed to explore the temporal age- and sex-specific profiles of temporal FPG variability in a Chinese population undergoing routine health screening and to guide the development of targeted public health interventions for the prevention and control of diabetes. Methods In this cross-sectional study, we used a general linear model to compare differences in temporal FPG values between sexes and across age groups in 101,886 Nanjing residents who underwent a routine physical health examination at the Health Management Center, the First Affiliated Hospital of Nanjing Medical University, in 2018. The variability of FPG as a function of time, age, and sex, independently and in combination, was analyzed. Results The participants included 57,455 (56.4%) males and 44,431 (43.6%) females, with a mean ± SD age of 42.8 ± 15.0 years. The average ± SD FPG level was 5.5 ± 1.1 mmol/L. The monthly variation contributed to 22% of the overall FPG variability. A significant main effect for the age group was observed (F = 7.39, P < 0.05), with an excellent fitting effect (Eta-squared =0.15). The variability of FPG showed sex differences in the percentage difference of the coefficient of variation, which was 34.1% higher in males than females. There were significant interaction effects for month*age*sex and day*age*sex. Conclusions Temporal variability in FPG is evident in the general Chinese population and is affected by both age and sex. To avoid complications associated with FPG variability, interventions should be directed at females and males at specific ages for optimal control of FPG variability and to reduce the risk of diabetes and cardiovascular events.

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Folate and Cobalamin Serum Levels in Healthy Children and Adolescents and Their Association with Age, Sex, BMI and Socioeconomic Status

Nutrients ◽

10.3390/nu13020546 ◽

2021 ◽

Vol 13 (2) ◽

pp. 546

Author(s):

Paulina Kreusler ◽

Mandy Vogel ◽

Anja Willenberg ◽

Ronny Baber ◽

Yvonne Dietz ◽

...

Keyword(s):

Socioeconomic Status ◽

Children And Adolescents ◽

Serum Levels ◽

Population Based ◽

Research Centre ◽

Healthy Children ◽

Serum Samples ◽

Lms Method ◽

Healthy Participants ◽

Age And Sex

This study proposes age- and sex-specific percentiles for serum cobalamin and folate, and analyzes the effects of sex, age, body mass index (BMI), and socioeconomic status (SES) on cobalamin and folate concentrations in healthy children and adolescents. In total, 4478 serum samples provided by healthy participants (2 months–18.0 years) in the LIFE (Leipzig Research Centre for Civilization Diseases) Child population-based cohort study between 2011 and 2015 were analyzed by electrochemiluminescence immunoassay (ECLIA). Continuous age-and sex-related percentiles (2.5th, 10th, 50th, 90th, 97.5th) were estimated, applying Cole’s LMS method. In both sexes, folate concentrations decreased continuously with age, whereas cobalamin concentration peaked between three and seven years of age and declined thereafter. Female sex was associated with higher concentrations of both vitamins in 13- to 18-year-olds and with higher folate levels in one- to five-year-olds. BMI was inversely correlated with concentrations of both vitamins, whilst SES positively affected folate but not cobalamin concentrations. To conclude, in the assessment of cobalamin and folate status, the age- and sex-dependent dynamic of the respective serum concentrations must be considered. While BMI is a determinant of both vitamin concentrations, SES is only associated with folate concentrations.

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AB0419 THE COEXISTENCE OF FAMILIAL MEDITERRANEAN FEVER (FMF) IN SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) PATIENTS - A CROSS SECTIONAL STUDY

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2020-eular.2305 ◽

2020 ◽

Vol 79 (Suppl 1) ◽

pp. 1509.1-1510

Author(s):

T. Klein ◽

S. Tiosano ◽

A. Chohen ◽

H. Amital

Keyword(s):

Systemic Lupus Erythematosus ◽

Familial Mediterranean Fever ◽

Lupus Erythematosus ◽

Cross Sectional Study ◽

Review Of The Literature ◽

Sectional Study ◽

Systemic Lupus ◽

Cross Sectional ◽

Mediterranean Fever ◽

Age And Sex

Background:Systemic Lupus Erythematosus (SLE) is a chronic autoimmune disease characterized by multisystem inflammatory lesions affecting many organ systems in the body. Familial Mediterranean fever (FMF) is an autosomal recessive disease of chronic autoimmune inflammation characterized by frequently relapsing self-limiting fever and inflammation that may be localized in peritoneum, pleura, joint or skin.1Previous studies have described the similarity of clinical symptoms of FMF among SLE patients. However, the literature on this topic is inconsistent and based mostly on case reports.2-4Objectives:To examine the proportions of coexistence of FMF among SLE patients compared to the general population. We hypothesized that the proportion of FMF among SLE patients is higher than the general population.Methods:This cross-sectional study used the Clalit Health Services database, the largest Health Maintenance Organization in Israel, serving 4,400,000 members. SLE patients were compared to age- and sex-matched controls. Chi- was used for univariate analysis.Results:The study included4886 SLEpatients and 24430 age- and sex-matched controls. The SLE group had a significantly higher proportion of FMF patients compared to non-SLE controls (0.68% and 0.21% respectively; p < 0.001).Table 1. All study populationTable 1.SLE patients and matched controls basic characteristicsNo SLESLEp.overallN=24430N=4886Age51.2±16.551.2±16.51.000Gender: Female20100 (82.3%)4020 (82.3%)1.000FMF52 (0.21%)33 (0.68%)<0.001Table 2. StratificationTable 2.comparison of FMF patients with and without SLEFMF without SLEFMF with SLEp.overallN=52N=33Age44.6±13.750.5±17.70.106Gender: Female45 (86.5%)26 (78.8%)0.523Conclusion:FMF was found to be more common amongst SLE patients compared to matched controls.The current study results suggest that the occurrence of SLE turn patients with an appropriate genetic and environmental setting to develop also FMF. This cross-sectional study sheds light on the coexistence of these two diseases, autoimmune and autoinflammatory.References:[1]Kucuk A, Gezer IA, Ucar R, Karahan AY. Familial mediterranean fever.Acta Medica (Hradec Kralove). 2014;57(3):97-104.[2]Lidar M, Zandman-Goddard G, Shinar Y, Zaks N, Livneh A, Langevitz P. SLE and FMF: A possible negative association between the two disease entities–report of four cases and review of the literature.Lupus. 2008;17(7):663-669.[3]Erten S, Taskaldiran I, Yakut ZI. Are systemic lupus erythematosus patients carrying MEFV gene less prone to renal involvement? report of three cases and review of the literature.Ren Fail. 2013;35(7):1013-1016.[4]Shinar Y, Kosach E, Langevitz P, et al. Familial mediterranean Fever gene (MEFV) mutations as a modifier of systemic lupus erythematosus.Lupus. 2012;21(9):993-998.Disclosure of Interests: :None declared

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Role of human epididymis protein 4 for detection of ovarian carcinoma in adnexal masses: A pilot study

10.1055/s-0039-1685305 ◽

2016 ◽

Author(s):

Nidhi Bansal ◽

A. Suneja ◽

K. Guleria ◽

N. B. Vaid ◽

K. Mishra ◽

...

Keyword(s):

Diagnostic Accuracy ◽

Cross Sectional Study ◽

Ca 125 ◽

Serum Samples ◽

Cross Sectional ◽

Adnexal Masses ◽

Good Discriminator ◽

Risk Of Malignancy ◽

Risk Of Malignancy Index ◽

Benign Tumours

Introduction: HE4 is a novel tumour biomarker used for early diagnosis of ovarian cancer. This study evaluated the diagnostic accuracy of HE4 alone and in combination with CA125, risk of malignancy index (RMI), risk of malignancy algorithm (ROMA). Methods: It was a cross sectional study conducted recruiting 88 women with adnexal masses who were planned for surgery. After baseline work up and ultrasound examination, serum samples were collected for estimation of CA 125 and HE4 levels. Serum HE4 levels were estimated using ELISA kit. RMI and ROMA score were calculated and diagnostic accuracy of HE4, CA 125, RMI, ROMA and their combination were compared. Cut off for HE4 and ROMA score were calculated using ROC curve. Results: Of 88 subjects, 66 were analyzed with 19 malignant (including 5 LMP) and 47 benign cases. The median value of HE4 among malignant cases was found to be significantly higher than among the benign cases. PPV and NPV of HE4 at a cut off 130.8 pMol/ml was 85.7% and 77.9% respectively. Highest PPV (88.9%) with acceptable NPV (80.7%) was found with ROMA followed by HE4 (PPV 85.7%; NPV 77.97%), RMI (PPV 76.92%; NPV 83%) and CA125 (PPV 52%; NPV 80.85%). Conclusion: HE4 levels were lower in Indian population both in malignant and benign tumours as compared to other studies. HE4 is a good discriminator and gives best accuracy when it is combined with CA125 in a logistic algorithm, ROMA.

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Evaluation of a Pseudovirus Neutralization Assay for SARS-CoV-2 and Correlation with Live Virus-Based Micro Neutralization Assay

Diagnostics ◽

10.3390/diagnostics11060994 ◽

2021 ◽

Vol 11 (6) ◽

pp. 994

Author(s):

Ahmed Majdi K. Tolah ◽

Sayed S. Sohrab ◽

Khaled Majdi K. Tolah ◽

Ahmed M. Hassan ◽

Sherif A. El-Kafrawy ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Epidemiological Studies ◽

Neutralization Assay ◽

Serum Samples ◽

Live Virus ◽

Spike Gene ◽

Microneutralization Assay ◽

Viral Particles ◽

Reliable Performance ◽

Prior Infection

The unusual cases of pneumonia outbreak were reported from Wuhan city in late December 2019. Serological testing provides a powerful tool for the identification of prior infection and for epidemiological studies. Pseudotype virus neutralization assays are widely used for many viruses and applications in the fields of serology. The accuracy of pseudotype neutralizing assay allows for its use in low biosafety lab and provides a safe and effective alternative to the use of wild-type viruses. In this study, we evaluated the performance of this assay compared to the standard microneutralization assay as a reference. The lentiviral pseudotype particles were generated harboring the Spike gene of SARS-CoV-2. The generated pseudotype particles assay was used to evaluate the activity of neutralizing antibodies in 300 human serum samples from a COVID-19 sero-epidemiological study. Testing of these samples resulted in 55 positive samples and 245 negative samples by pseudotype viral particles assay while microneutralization assay resulted in 64 positive and 236 negative by MN assay. Compared to the MN, the pseudotyped viral particles assay showed a sensitivity of 85.94% and a specificity of 100%. Based on the data generated from this study, the pseudotype-based neutralization assay showed a reliable performance for the detection of neutralizing antibodies against SARS-CoV-2 and can be used safely and efficiently as a diagnostic tool in a biosafety level 2 laboratory.

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