Analysis of related factors of plasma antibody titer in convalescent patients with COVID-19 / 中国输血杂志

【Objective】 To study the relationship between the plasma IgG, IgM, neutralizing antibody titer and sex, age, collection interval in convalescent patients with COVID-19, so as to guide the plasma collection of convalescent patients with COVID-19. 【Methods】 COVID-19 convalescent plasma was collected to determine the antibody titer, and the difference and correlation of data in each group were analyzed by SPSS statistical analysis software. 【Results】 The median titers (AU/mL)of IgG, IgM and neutralizing antibodies in males and females were 484.24 vs 516.04, 2.13 vs 1.73, and 1 124.74 vs 1 143.99, respectively, and there was no significant difference(P>0.05) . Age had weak positive correlation with IgG and neutralizing antibody, and the Spearman correlation coefficient was 0.188 (P<0.05). The median titers (AU/mL) of IgG, IgM and neutralizing antibody at first donation of 30 repeated donors were 522.3, 2.64 and 1 174.6, respectively, but at second donation were 332.08, 0.63 and 708.96, showing significant difference (P<0.05). 【Conclusion】 There was no significant difference in the plasma IgG, IgM and neutralizing antibody titers in convalescent COVID-19 patients of different ages and genders, and the titers met the requirements of clinical treatment guidelines. Although the plasma antibody level of repeated donors has decreased, it still has clinical value.

Analysis of monitoring results of novel coronavirus IgM and IgG antibody levels in apheresis platelets donors and impact on blood safety / 中国输血杂志

【Objective】 To monitor the positive rates of IgM and IgG antibodies and the changes in S/CO values over time in voluntary blood donors infected with SARS-CoV-2 after recovery, in order to provide theoretical basis and data support for ensuring clinical blood safety. 【Methods】 A total of 54 platelet donors who met the inclusion criteria were selected for this study, and 359 blood samples (plasma) from T1 to T7 (at 7 time points, spanning 14 to 15 weeks) were continuously monitored for SARS-CoV-2 IgM and IgG antibodies using fully automated chemi-luminescence method. 【Results】 Among 359 blood samples (plasma) from 54 donors, 349 were with valid test results.Eleven donors were tested positive for IgM, with a positive rate of 20.37%, and IgM antibody S/CO value gradually increased during T1-T3, but gradually decreased during T4-T7. Fifty-four donors were tested positive for IgG, with the positive rate of 100%, and the S/CO value of IgG antibody gradually decreased over time. During the period of T1 -T7, there was no significant difference in SARS-CoV-2 IgG antibody S/CO value between gender (male/female) or age group (18-39 years old /40-60 years old). 【Conclusion】 The positive rate of SARS-CoV-2 IgG antibody in platelet donors after recovery from SARS-CoV-2 infection was 100% during 2-14 weeks, and the IgG S/CO value gradually decreases over time. The long-term dynamic changes of SARS-CoV-2 serologically specific IgG and IgM antibodies in blood donors are worthy of further study.

Clinical value of 1, 3-β-D glucan and mannan IgM/IgG antibodies in the early diagnosis of invasive candidiasis / 中华微生物学和免疫学杂志

Objective:To evaluate the diagnostic value of 1, 3-β-D glucan (BDG), mannan IgM antibody (Mn-IgM) and mannan IgG antibody (Mn-IgG) in invasive candidiasis and to compare the differences in the diagnostic capability of serological markers used alone or in combination.Methods:Serum samples of 126 patients with invasive candidiasis and 104 healthy people who took physical examination during the same period were collected. BDG was detected by dynamic chromogenic method, and Mn-IgM and Mn-IgG were detected by ELISA. The sensitivity, specificity, positive predictive value, negative predictive value, Youden index, coincidence rate and Kappa value of the three serological markers used alone or in combination in the diagnosis of invasive candidiasis were analyzed and compared. The receiver operating characteristic (ROC) curves were drawn and the areas under the curves (AUCs) were calculated.Results:The levels of BDG, Mn-IgM and Mn-IgG in patients with invasive candidiasis were significantly higher than those in healthy people ( P<0.01). The sensitivity, specificity, Kappa value and AUC of BDG were 48.41%, 92.31%, 0.389 and 0.842. The sensitivity, specificity, Kappa value and AUC of Mn-IgM were 64.29%, 91.35%, 0.540 and 0.829. The sensitivity, specificity, Kappa value and AUC of Mn-IgG were 27.78%, 95.19%, 0.214 and 0.737. The sensitivity, specificity, Kappa value and AUC of BDG+ Mn-IgM were 76.19%, 88.46%, 0.637 and 0.921. The sensitivity, specificity, Kappa value and AUC of BDG+ Mn-IgG were 59.52%, 91.35%, 0.491 and 0.856. The sensitivity, specificity, Kappa value and AUC of Mn-IgM+ Mn-IgG were 69.84%, 90.38%, 0.588 and 0.891. The sensitivity, specificity, Kappa value and AUC of BDG+ Mn-IgM+ Mn-IgG were 80.16%, 88.46%, 0.679 and 0.922. Conclusions:The sensitivity of Mn-IgM was higher than that of BDG and Mn-IgG in the diagnosis of invasive candidiasis. When the serological biomarkers were used in combination, BDG+ Mn-IgM and BDG+ Mn-IgM+ Mn-IgG had relatively high Kappa value and AUC, showing high accuracy. The clinical diagnostic value of multiple serological biomarkers used in combination was significantly higher than that of any serological biomarkers used alone. Early combined detection and continuous monitoring of multiple serological biomarkers in patients with high risk of invasive candidiasis could be used clinically to adjust antifungal treatment strategies timely.

Results of serum antibody detection from patients with hemorrhagic fever with renal syndrome in Heilongjiang, 2019-2021 / 中国热带医学

@#Abstract: Objective　To detect the antibody levels of hantavirus in serum samples from patients suspected with hemorrhagic fever with renal syndrome (HFRS) in Heilongjiang Province from 2019 to 2021, and to provide scientific basis for the prevention and control of disease. Methods　Enzyme-linked immunosorbent assays (ELISA) were used to detect the IgM antibodies to hantavirus in serum samples collected from suspected patients with HFRS in the acute-phase, and IgM and IgG antibody in convalescent-phase serum samples. The positive rate of IgM antibody in acute-phase serum samples of patients in different years was analyzed with χ2 test by SPSS 19.0, and the data were sorted out and analyzed about patients' gender, occupation, age, date of onset and interval from onset to initial diagnosis by EpiData 3.1, Excel 2003 software. Results　A total of 351 acute-phase serum samples and 208 convalescent-phase serum samples were detected in patients suspected with HFRS, respectively. There were 317 positive IgM antibodies of serum samples in the acute stage, with the positive rate of 90.31%. There was no significant difference in the positive rate of IgM antibodies in the acute stage between different years (χ2=0.895, P=0.639). T The IgM antibodies and IgG antibodies were positive in 32 (15.39%) and 28 (13.46%) of the convalescent-phase serum samples, respectively. Moreover, 148 patients (71.15%) were double-positive for IgM and IgG antibodies at the convalescent stage. The ratio of male to female patients was 4.56∶1, for which male patients were much more than female patients. Occupation was dominated by farmers (253 cases, 79.81%), followed by workers (19 cases, 5.99%) and the unemployed (17 cases, 5.36%), respectively. The age of patients ranged from 10 to 88 years old, with a median age of 49 years old. Most of the patients were in the age group from 30 years old to 60 years old (209 cases, 65.93%), among which the age group from 40 years old to 50 years old (86 cases, 27.13%) had the highest proportion, and the age group from 60 years old to 90 years old had a proportion of 20.18% (19 cases). May and November were the peak periods of HFRS in Heilongjiang Province. The median interval between onset and initial diagnosis was 4 days. Conclusions　There is a gap of about 10% between the clinical diagnosis of HFRS cases and the confirmed cases detected by laboratory in Heilongjiang Province from 2019 to 2021. The virus-specific detection results are important for confirming the diagnosis of local patients with HFRS.

Advances in the diagnosis and treatment of hyper-IgM syndrome in children / 国际儿科学杂志

The hyper immunoglobulin M syndrome(hyper-IgM syndrome, HIGM)is a rare X-linked inherited primary immunodeficiency disease(PID)characterized by defective class switch recombination(CSR)with or without somatic hyper mutation(SHM), resulting in normal or increased levels of serum IgM associated with deficiency of immunoglobulin G(IgG), immunoglobulin A(IgA), and immunoglobulin E(IgE)and antibody dysfunction.Most cases have X-linked recessive inheritance, and a few are autosomal-recessive forms.The clinical manifestations include recurrent infections in early age, tumors and autoimmune diseases.The prognosis is poor, especially for HIGM with X-linked recessive inheritance.And if these patients do not be treated timely after birth, most of them will die early.In order to improve pediatricians′ understanding of the disease, and to timely identify and treat HIGM for an improved prognosis, this paper reviews the pathogenesis, clinical manifestations, diagnosis and treatment of HIGM.

Seroprevalence of acute leptospirosis in a tertiary care hospital of western India

Background: Leptospirosis is a widespread re-emerging zoonotic disease, especially in developing countries. According to World Health Organization, despite being severe, the disease is neglected in most endemic countries because of a lack of information and awareness about the extent of the problem. Objective: The objective was to study the seroprevalence and epidemiology of leptospirosis with its biochemical correlation in the general population in Pune, Maharashtra. Materials and Methods: It is a retrospective observational laboratory-based study over 1 year from January to December 2020 in a tertiary care hospital in western India. A total of 561 blood specimens received during 1 year for the diagnosis of fever were processed for Leptospira IgM antibodies using enzyme-linked immunosorbent assay (ELISA). Results: A total of 111 of 561 blood specimens that were received during the study period tested positive for IgM antibody against Leptospira. The seroprevalence of Leptospira spp. was found to be 19.78%. In seropositive patients, the age ranged from 4 to 77 years. The highest seropositivity was observed in the age group of 21–30 years (42%). There were 34% (n = 38) males and 66% (n = 73) females, among those who tested positive. Seroprevalence in Pune was highest in the months of June–August. Renal function tests were deranged in 44 (39.63%) patients (serum creatinine > 1.5 mL). Hyponatremia and hypokalemia were observed in 37.84% and 21.62% of patients, respectively. In liver function tests, serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) both were deranged (SGOT > 40 U/L; SGPT > 56 U/L) in 36 (32.43%) patients, whereas SGOT alone was deranged in additional 18 patients (48.64%). Serum bilirubin was deranged in 65.45%. Coinfection was observed with chikungunya, dengue, and malaria in 7.2%, 6.3%, and 0.90% of patients, respectively. Conclusion: Because morbidity is high in this infection, early diagnosis of leptospirosis is essential because antibiotic therapy provides the greatest benefit when initiated early in the course of illness.

Rendimiento diagnóstico de la prueba rápida para la detección del antígeno NS1 y anticuerpos IgM e IgG contra el virus del dengue / Diagnostic performance of the rapid test for the detection of NS1 antigen and IgM and IgG anti-antibodies against dengue virus

Objetivos. Determinar el rendimiento diagnóstico de la prueba rápida SD dengue DUO (Inyecta) para la detección de NS1, IgM e IgG en comparación con la prueba de ELISA. Materiales y métodos. Es una evaluación de prueba diagnóstica que incluyó 286 muestras de suero de pacientes con sintomatología atribuible a dengue de zonas endémicas del Perú. Las muestras se analizaron por ELISA y la prueba rápida SD dengue DUO (Inyecta) para IgM, NS1 e IgG en el Instituto de Investigación Nutricional en Lima. Resultados. La sensibilidad de la prueba rápida fue de 68% para NS1 e IgM, y 86% para IgG, mejorando este parámetro a 75% y 81% para NS1 e IgM, respectivamente, en los tres primeros días. La especificidad para los tres analitos fue mayor a 87%. La concordancia de los resultados obtenidos medidos por el coeficiente Kappa para los tres analitos fue buena y no se encontró reacción cruzada con otros arbovirus. Conclusiones. La prueba rápida SD Dengue DUO permite detectar con una adecuada sensibilidad y especificidad NS1, IgM e IgG. La sensibilidad para IgM y NS1 aumenta cuando se detecta en los tres primeros días de síntomas, por lo que se recomienda su implementación en los centros de primer nivel de atención para un diagnóstico temprano y oportuno.

Objectives . To assess the diagnostic performance of the SD dengue DUO rapid test (Inyecta) for the detection of NS1, IgM and IgG in comparison to the ELISA test. Materials and methods . This is a diagnostic test evaluation that included 286 serum samples from patients with symptomatology attributable to dengue from endemic areas of Peru. The samples were analyzed by ELISA and the SD dengue DUO rapid test (Inyecta) for IgM, NS1 and IgG at the Instituto de Investigación Nutricional in Lima. Results . The sensitivity of the rapid test was 68.0% for NS1 and IgM, and 86.0% for IgG, improving to 75.0% and 81.0% for NS1 and IgM, respectively, during the first three days. The specificity for all three analytes was greater than 87.0%. The concordance of the results, measured by the Kappa coefficient for the three analytes, was good and no cross-reaction with other arboviruses was found. Conclusions . The SD dengue DUO rapid test allows detection of NS1, IgM and IgG with adequate sensitivity and specificity. Sensitivity for IgM and NS1 increases when detected during the first three days of symptoms. Therefore, we recommend its implementation in primary care centers for early and timely diagnosis.

Demographic and Clinical Profile Analysis of Acute Viral Hepatitis

Background: Acute viral hepatitis (AVH) is a major health concern in developing countries like Bangladesh regarding morbidity as well as mortality. Usually, acute infections are caused by A, E, hepatitis viruses, and occasionally hepatitis B virus. Infection caused by the hepatitis C virus is usually asymptomatic. Prior knowledge of the demographic and clinical profile of acute viral hepatitis may be helpful for treatment professionals in the management of such patients. Aim of the study: The aim of this study was to assess the demographic and clinical profile of acute viral hepatitis patients in Bangladesh.Material & Methods:This prospective observational study was conducted in the Department of Gastroenterology, US-Bangla Medical College & Hospital during the period from March 2018 to February 2019, in Bangladesh. A total of 59 suspected patients with acute viral hepatitis were included as the study subjects for this study. Ethical approval of the study had been taken from the ethical committee of the mentioned hospital. A predesigned questionnaire was used in data collection. Collected data analyzed by using MS Office and SPSS version 23.0 programs as per need. A P-value, of <0.05 was considered significant.Results:Among 59 participants, the male-female ratio was 3.2:1 and the mean (±SD) age was 23.88±14.83 years. Analyzing hepatitis infection, we found hepatitis E was the highest in number 32(54.24%), followed by hepatitis E virus 20(33.9%), and hepatitis B virus 5(8.47%). In this study, we did not find any patients with hepatitis C virus, and 2 participants didn’t have any hepatotropic virus. The mean (±SD) Serum bilirubin (mg/dl) was 6.35±1.63, and the mean (±SD) serum alkaline phosphatase (IU/L), serum. creatinine (mg/dl), serum albumin (gm/dl) and plasma glucose random (mg/dl) were found 366.81±257.20, 6.97±14.96, 19.75±22.98 and 10.08±5.49 respectively. Considering dual viruses among the total of 5 patients along with hepatitis E & A viruses in this study, we found all were hepatitis B viruses. Among them, 3 with hepatitis E and the rest 2 were with hepatitis A virus consequently. Among them 3(60%) with hepatitis A and the rest 2(40%) with hepatitis E. In the issue of patients attended with clinical complaints, vomiting was the highest among hepatitis A patients 19(86.4%) followed by jaundice 8(36.4%) and fever8(36.4%). On the other hand, among hepatitis E patients’ jaundice was highest at 19(61.3%) followed by vomiting at 17(54.8%), and fever at 6(19.4%) respectively.Conclusions:The incidence of HEV is found as the most predominant among all the acute viral hepatitis patients and vomiting and jaundice were the most common presenting complaints.

A case report on leptospirosis with pseudohepatorenal syndrome

The spirochete Leptospira interrogans causes leptospirosis, a zoonosis. There are numerous clinical symptoms of leptospirosis. Clinical manifestations might range from a subclinical infection with a mild fever to severe clinical symptoms with jaundice and renal failure. Here, a case of leptospirosis with acute renal failure, thrombocytopenia, and hyperbilirubinemia is presented. A 51-year-old man presented with fever, body aches, muscle aches, colored urine, and jaundice for 2 days. On serology report, L. interrogans AB IGM-CARD was weekly positive. In the Renal function test, urea and creatinine values were high as well as the liver function test was abnormal. The patient was given 1 g of ceftriaxone intravenously and 100 mg of doxycycline orally. Hepatorenal treatment was supportive and the outcome was positive. It may have been overlooked when the diagnosis of leptospirosis was confirmed.

Hepatitis D virus seroprevalence in HBsAg positive patients attending a tertiary care hospital in Northeast India

Background:Hepatitis D virus (HDV) infection is present worldwide. Around 18 million people are estimated to be infected with HDV and can infect individuals with active HBV infection and cause severe liver disease. There is lack of data on the prevalence of HDV infection in the state and also in the region. The aim of the study was to determine the seroprevalence of HDV in HBsAg positive patients attending Regional Institute of Medical Sciences Hospital, Imphal, Manipur, India.Methods:This study was carried out in a tertiary care hospital (Regional Institute of Medical Sciences, Imphal).The study was done for a period of 2 years from September 2016 to August 2018. A total of 119 HBsAg ELISA positive cases were included in the study.Results:Out of 119 HBsAg positive cases, 5 cases were positive for hepatitis D antibodies, of which 3 were positive for anti-Hepatitis D virus IgM and 2 were positive for anti-Hepatitis D virus IgG.Seroprevalence of HDV infection was found to be 4.2%.Conclusions:Seroprevalence of HDV infection was found to be 4.2% which is higher than the finding in some of the recent studies in the country.

Evaluación de ensayos ultramicroanalíticos para la detección de anticuerpos contra el SARS-CoV-2 / Evaluation of ultramicroanalytic assays to detect antibodies against SARS-CoV-2

Introducción: En el presente trabajo se muestran los resultados de la validación de los ensayos serológicos in vitro para la detección de anticuerpos IgM, IgG y anticuerpos totales contra el SARS-CoV-2 UMELISA SARS-CoV-2 IgM, UMELISA ANTI-SARS-CoV-2 y UMELISA SARS-CoV-2 IgG desarrollados por el Centro de Inmunoensayo (CIE). Métodos: Se utilizaron paneles de muestras de suero de individuos negativos y de casos confirmados de COVID-19 para determinar el desempeño analítico de cada ensayo. Resultados: La especificidad clínica de los ensayos UMELISA SARS-CoV-2 IgM, UMELISA ANTI-SARS-CoV-2 y UMELISA SARS-CoV-2 IgG fue del 100 por ciento en todos los ensayos y la especificidad analítica fue de 100 por ciento para los dos primeros ensayos y del 93,1 por cientopara el último. La sensibilidad clínica fue de 64,3, 80,8 y 97,5 por ciento, respectivamente. El valor predictivo positivo fue de 100 por ciento en todos los ensayos, en tanto que el negativo osciló entre 83,3 y 95,2 por ciento. La concordancia fluctuó entre 92,4 y 96,9 por ciento y el índice kappa de todos los ensayos fue muy bueno. La sensibilidad de los ensayos se incrementó a 82,76, 96,5 y 100 por ciento, respectivamente, en las muestras de suero colectadas con más de 14 días de iniciado el cuadro clínico. Conclusiones: Los ensayos demostraron una elevada sensibilidad y especificidad, lo que permite contar con herramientas basadas en una tecnología desarrollada en Cuba que posibilita la realización de estudios serológicos, vigilancia epidemiológica y de otro tipo, incluyendo los relacionados con vacunas en una plataforma con amplia distribución nacional(AU)

Introduction: This paper shows the results obtained in the validation of in vitro serological assays to detect IgM, IgG antibodies, and total antibodies against SARS-CoV-2 UMELISA SARS-CoV-2 IgM, UMELISA ANTI-SARS-CoV-2 and UMELISA SARS-CoV-2 IgG developed by the Immunoassay Center. Methods: Panels of serum samples from negative and COVID-19 confirmed patients were used to determine the analytical performance of each assay. Results: UMELISA SARS-CoV-2 IgM, UMELISA ANTI-SARS-CoV-2 and UMELISA SARS-CoV-2 IgG assays demonstrated 100 percent clinical specificity for all assays; and 100 percent analytical specificity for the first two assays, and 93.1 percent for the last one. Clinical sensitivity was 64.3 percent, 80.8 percent and 97.5 percent, respectively. The positive predictive value was 100 percent in all assays, while the negative predictive value ranged from 83.3 percent to 95.2 percent. Concordance varied from 92.4 percent to 96.9 percent, and kappa index in every assay was very good. Assays sensitivity increased to 82.7 percent, 96.5 percent and 100 percent, respectively for serum samples collected more than 14 days after onset of the symptoms. Conclusions: The assays demonstrated high sensitivity and specificity, which allows us to have Cuban technology-based tools for serological, epidemiological surveillance, and other types of studies, including those related to vaccines on a platform with wide national distribution(AU)

Development of Nipah virus-specific IgM & IgG ELISA for screening human serum samples

Background & objectives: Nipah virus (NiV) is a zoonotic paramyxovirus that causes fatal encephalitis in humans. Enzyme Linked Immunosorbent Assay (ELISA) is a safe, sensitive, specific, and affordable diagnostic tool that can be used during screening of large-scale epidemiological investigations. Development and evaluation of IgM and IgG ELISA for screening serum samples of NiV suspected cases would also help in planning public health interventions. Methods: An IgM capture (MAC) ELISA and an indirect IgG ELISA were developed using NiV antigen to detect IgM and IgG antibodies against NiV in human sera. The sensitivity, specificity, and cross- reactivity of the assays were evaluated using NiV IgM, IgG positive, negative human sera and measles, mumps, rubella, Crimean-Congo haemorrhagic fever, Kyasanur forest disease IgM, IgG positive sera, respectively. Results: The developed anti-NiV IgM and IgG ELISAs have shown specificity of 99.28 per cent and sensitivity of 100 per cent compared to reference test from Centers for Disease Control and Prevention, USA. Assays demonstrated negative predictive value of 100 per cent and positive predictive value as 90 and 93.94 per cent for anti-Nipah IgM ELISA and IgG ELISA respectively with test accuracy of 99.33 per cent. Interpretation & conclusions: Timely diagnosis of NiV is crucial for the management of cases, which could prevent further spread of infection in the community. IgM ELISA can be used as primary diagnostic tool followed by polymerase chain reaction. These assays have advantages of its applicability during outbreak investigations and surveillance activities at hospital or onsite laboratories with basic biosafety practices.

COVID immunity in the Angolan population :Serological study with Abbott COVID-19 IgG/IgM Rapid Test and serological mini VIDAS BIOMERIEUX test

Background: The numbers of severe COVID cases and COVID-related deaths on the African continent are lower than expected. We hypothesize that this paradox may be due to the achieved immunity in black Africans. Materials and Methods: A prospective study was conducted on Angolan people who performed the Panbio Abbott COVID-19 IgG/IgM Rapid Test in a health unit in Luanda. One hundred randomly selected subjects in those with positive immunoglobulin G (IgG) underwent the serological mini VIDAS BIOMERIEUX test. Results: In our population study (2409 subjects), 791 (32.83%) had positive IgG at the Panbio Abbott COVID-19 test. One hundred were randomly selected. The mean age was 39.55, and 96% were males. The positivity to IgG was validated in 72 subjects at the mini VIDAS BIOMERIEUX test. Conclusion: These results support our hypothesis that in the Angolan/African population a previously achieved immunity may be one of the reasons why this continent was not affected by COVID-19 as expected.

Sero-molecular Epidemiology of Hepatitis E Virus in Blood Donors, Gezira State, Sudan: A Cross-sectional Study

Background: Hepatitis E virus (HEV) is a hepatotropic pathogen that causes significant morbidity and mortality in humans. It is an important causative agent of viral hepatitis outbreaks. This study investigates the serological and molecular prevalence of HEV in blood donors attending the Central Blood Bank in Wad Medani City in Gezira State, Sudan. Methods: The study adopted a cross-sectional descriptive design. A structured questionnaire was used to collect data concerning demographic information and risk factors associated with HEV transmission. All enrolled participants (N = 300) were screened for HEV IgG antibodies using commercial ELISA kits, then strong positive samples (N = 84) were selected and rescreened for HEV IgM and HEV RNA by RT PCR. SPSS version 24.0 was used for analysis. Results: Out of 300 male participants, 36.3% (109/300) were positive for HEV IgG. However, only one participant was IgM positive, while the HEV RNA was negative. The highest prevalence rates of the virus were 42 (44.6%) among the age group of 31­40 years, 20 (48.8%) in those who consumed food from outside, 13 (50%) in three to four multiple blood donations, and 5 (62.5%) in those who consumed water from the river source. A significant association of HEV IgG prevalence concerning the occupation of the participants being students or farmers was detected using univariate and multivariate analysis (P-value = 0.007).

Study on the immune status of blood donors in Yangzhou after SARS-COV-2 vaccinating / 中国输血杂志

【Objective】 To investigate the immune status of blood donors in Yangzhou area after SARS-COV-2 vaccinating. 【Methods】 Among 112 voluntary blood donors from August 29 to September 22, 2021, 111 were vaccinated with SARS-COV-2 vaccine.IgM antibody(by enzyme-linked immunocapture method), IgG antibody(by indirect method of combined immunoassay)and IgG antibody titer were detected. 【Results】 A total of 99.11% (111/112 ) voluntary blood donors were vaccinated, two-shot(n=103), one-shot(n=1) and three-shot (n=7) accounting for 91.96%, 0.89% and 6.25%, respectively.Eighty-eight (78.57%) were positive for IgG antibodies, and 14 (12.5%) were positive for IgM antibodies.No statistically significant difference was found in IgG and IgM positive yielding between males and females (P>0.05). The proportion (0.89%, 1/112) of positive IgM in blood donors with blood type A was significantly lower than that of other blood types (P<0.01). The IgG antibody titer of blood donors maintained rather high level within 6 months after vaccinating.47.66% of the donors presented antibody titer more than 160, and 5.60% had IgM antibody been detected within 1 month after vaccinating. 【Conclusion】 At present, the SARS-COV-2 vaccination effect in China is generally good.Since IgG antibodies cannot be detected after 6 months, it is suggested to perform IgG antibody testing for donors who have completed the second dose for more than 6 months.For those IgG antibody negative, booster shots should be conducted.For donors with high IgG antibody titer, their plasma may be considered to replace with COVID-19 convalescent plasma for the treatment of patients with rapid disease progression, or severe/critically ill patients diagnosed with COVID-19, so as to avoid the risk of COVID-19 re-spreading during convalescent plasma collection in blood centers. For blood donors with positive IgM antibodies, it is recommended to follow up the NAT results to minimize the risk of transmission.

Assessment of 3 enzyme linked immunosorbent assays and 1 pseudotype lentivirus-based neutralization test in detecting serum antibody in convalescent plasma from COVID-19 / 中国输血杂志

【Objective】 To assess three severe acute respiratorysyndrome coronavirus 2 (SARS-CoV-2) enzyme linked immunosorbent assays (ELISA) and one pseudotype lentivirus-based neutralization test (ppNAT) in detecting the convalescent plasma antibody levles from COVID-19. 【Methods】 30 COVID-19 convalescent plasma samples were screened for antibodies against SARS-CoV-2 using three kinds of SARS-CoV-2 ELISA reagents and one ppNAT test in Shenzhen. The controls consisted of plasma samples from 32 healthy blood donors in February 2019. The diagnostic efficacy analysis of various SARS-CoV-2 ELISA reagents was performed using real-time fluorescent Polymerase Chain Reaction (RT-PCR). We also analyzed correlation between different immunological reagents and the age, gender, hospitalization, and severity of illness. 【Results】 The positive yielding rate of ppNAT and three kinds of IgG ELISA was higher than that of IgM ELISA. The positive yielding rates of three kinds of IgG ELISA were 100%(30/30), 93.33%(28/30), and 96.67%(29/30) respectively, while the yielding rates in control group were all 0. The positive yielding rate of three IgM ELISAs were 93.33%(28/30), 70%(21/30)and 46.67% (14/30). All the cases from negative control group were negative for IgG and IgM. Pearson correlation coefficient was calculated; there was a strong correlation between ELISA reagent 2 IgG and ELISA reagent 3 IgG (r=0.765, P0.05). 【Conclusion】 In the convalescent plasma with nucleic acid confirmed covid-19, the yielding rates of different IgM antibodies varied greatly. Antibody levels were influenced by age to some extent.

Serum IgM and IgG antibody response six months post-COVID-19 vaccination / 上海预防医学

Objective To determine the serum IgM and IgG antibody levels post-COVID-19 vaccination， and provide scientific evidence for COVID-19 antibody response after vaccination. Methods A total of 980 healthy persons were included in Kunming Third People’s Hospital from July through August， 2021， which had been vaccinated with COVID-19 vaccines and then tested for anti-SARS-CoV-2 IgM and IgG antibodies. Results After the COVID-19 vaccination， 469 persons （positive rate， 47.86%） were positive for anti-IgG antibody. Of them， 75 were males with （positive rate， 39.06%）， and the average IgG level was 0.618 （0.180， 2.526） AU·mL-1［M（Q1，Q3）］； 394 were females （50.00%）， and the IgG level was 0.999 （0.305， 3.334） AU·mL-1. In addition， 53 persons （5.41%） were anti-IgM antibody positive. Of them， 14 were males （positive rate， 7.29%）， and the average IgM level was 0.057 （0.026， 0.195） AU·mL-1； 39 were females （4.95%）， and the IgM level was 0.047 （0.027， 0.110） AU·mL-1. The positive rate of anti-IgG antibody was highest in those aged ≤30 years， which was 51.02% in male （n=25） and 55.88% in female （n=133）. The anti-IgG response differed significantly by gender （χ2=7.401， D=0.135 1， P<0.05）， whereas the anti-IgM response was not significantly different （χ2=1.656， P>0.05）. Among the age groups， anti-IgG antibody level was higher in those aged ≤30 and 51-70 years， with 158 （55.05%） and 122 （52.36%） persons， respectively； the average antibody level was 1.209 （0.426， 4.386） AU·mL-1 and 1.074 （0.191， 7.670） AU·mL-1， respectively. The differences in the positive rates of IgG and IgM antibodies and the levels of IgG antibodies among different age groups were statistically significant （P<0.05）. Using Kruskal-Wallis test and Spearman correlation analysis， it showed a high correlation between the IgG and IgM antibodies （r=0.836 4， H=64.82， 20.09， P<0.05）. Conclusion The Anti-SARS-CoV-2 IgG antibody remains high six months post-COVID-19 vaccination， while anti-IgM antibody is low. The IgM and IgG response are higher in the young and elderly. The response differs by gender and age， demonstrating a correlation.

Evaluation of efficiency of different anti-cysticercus antibody test kits for serodiagnosis of cysticercosis / 中国血吸虫病防治杂志

Objective To evaluate the diagnostic efficiency of four anti-cysticercus IgG, IgG4 or IgM antibody test kits (enzyme-linked immunosorbent assay, ELISA) by different manufacturers, so as to provide insights into the epidemiological investigation and clinical detection of cysticercosis. Methods Forty serum samples from cerebral cysticercosis patients, 100 serum samples from healthy volunteers, 30 serum samples from paragonimiasis skrjabini patients, 17 serum samples from cystic echinococcosis and 19 serum samples from subcutaneous or cerebral sparganosis patients were collected and detected using anti-cysticercus IgG, IgG4 or IgM antibody test kits (brand A) and the anti-cysticercus IgG antibody test kit (brand B). The sensitivity, specificity and false negative rate of the four kits for detection of cysticercosis were estimated. Results The anti-cysticercus IgG, IgG4 or IgM antibody test kits (brand A) showed 95.00% (38/40), 87.50% (35/40), 7.50% (3/40) sensitivities and 98.00% (98/100), 100.00% (100/100) and 100.00% (100/100) for detection of cysticercosis, while the anti-cysticercus IgG antibody test kit (brand B) presented a 75.00% (30/40) sensitivity and 100.00% (100/100) specificity for detection of cysticercosis. The sensitivity for detection of cysticercosis was significantly higher by the anti-cysticercus IgG antibody test kit (brand A) than by the anti-cysticercus IgG antibody test kit (brand B) (χ2 = 6.28, P < 0.05); however, no significant difference was seen in the specificity by two kits (χ2 = 2.01, P > 0.05). The four ELISA kits showed overall false positive rates of 37.88% (25/66), 22.73% (15/66), 62.12% (41/66) and 15.15% (10/66) for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 37.61, P < 0.05), and the anti-cysticercus IgG antibody test kit (brand A) presented the highest overall false positive rate for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 7.56, P’ < 0.008), while a higher overall false positive rate was seen for detection of paragonimiasis, echinococcosis and sparganosis by the anti-cysticercus IgG antibody test kit (brand A) than by the anti-cysticercus IgG antibody test kit (brand B) (χ2 = 8.75, P’ < 0.008). The four ELISA kits showed false positive rates of 40.00% (12/30), 16.67% (5/30), 76.67% (23/30) and 13.33% (4/30) for detection of paragonimiasis (χ2 = 32.88, P < 0.05) and 21.05% (4/19), 26.32% (5/19), 73.68% (14/19) and 15.79% (3/19) for detection of sparganosis (χ2 = 19.97, P < 0.05), and the highest false positive rates were found by the anti-cysticercus IgM antibody test kit (brand A) for detection of paragonimiasis and sparganosis (all P’ < 0.008). However, the four ELISA kits showed comparable false positive rates of 52.94% (9/17), 29.41% (5/17), 23.53% (4/17) and 17.65% (3/17) for detection of echinococcosis (χ2 = 8.24, P > 0.05). In addition, the anti-cysticercus IgM anti-body test kit (brand A) showed false positive rates of 76.67% (23/30), 23.53% (4/17) and 73.68% (14/19) for detection of paragonimiasis, echinococcosis and sparganosis (χ2 = 14.537, P < 0.05), with the lowest false positive rate seen for detection of echinococcosis (χ2 = 14.537, P’ < 0.014), while no significant differences were seen in the false positive rate for detection of paragonimiasis, echinococcosis and sparganosis by other three ELISA kits (all P > 0.05). Conclusions The four anti-cysticercus IgG, IgG4 or IgM antibody test kits exhibit various efficiencies for serodiagnosis of cysticercosis. The anti-cysticercus IgG antibody test kit (brand A) has a high sensitivity for serodiagnosis of cysticercosis; however, it still needs to solve the problems of cross-reaction with other parasitic diseases and stability.

Clinical characteristics and serum IgG, IgM antibody manifestations of patients infected with SARS-CoV-2 B.1.1.529 (Omicron) variant strain / 中国热带医学

@#Abstract: Objective　To analyze the clinical characteristics and changes of serum IgG, IgM antibodies in patients infected with the SARS-CoV-2 B.1.1.529 (Omicron) variant. Methods　The clinical data of 82 patients with SARS-CoV-2 B.1.1.529 variant was analyzed retrospectively. Based on the presence of pneumonia on chest CT, the patients were divided into pneumonia group and non-pneumonia group. Serum IgG, IgM antibodies were observed at 5 time points T1 (1~<4 d), T2 (4~<8 d), T3 (8~<15 d), T4 (15~<22 d) and T5 (22~<30 d) after admission. Results　Among the 82 patients infected with the SARS-CoV-2 B.1.1.529 variant strain, there were 62 cases of cough, 31 cases of fever, 33 cases of throat discomfort, 5 cases of muscle soreness and 3 cases of diarrhea. The serum IgG antibody levels at 5 time points were 50.22 (142.20) AU/mL, 326.50 (220.63) AU/mL, 368.23 (76.21) AU/mL, 368.65 (79) AU/mL, and 385.26 (113.10) AU/mL, respectively. The level of serum IgG antibody in the pneumonia group was lower than that of the non-pneumonia group at T1 and T4 time points, and the differences were statistically significant (P<0.05) , the positive rate of serum IgG antibody in the pneumonia group was lower than that of the non-pneumonia group at the T1 time point, and the difference was statistically significant (P<0.05) . The serum IgM antibody levels at 5 time points were 0.41 (0.81) AU/mL, 0.95 (1.62) AU/mL, 1.09 (2.42) AU/mL, 0.74 (3) AU/mL, and 0.81 (3.10) AU/mL respectively, and there was no significant difference between the two groups. Conclusion　The clinical symptoms of patients infected with the SARS-CoV-2 B.1.1.529 variant strain are mild. Serum IgG antibodies increased after infection, but there are some differences between the pneumonia group and the non-pneumonia group, whether serum IgG has a protective effect needs further research; the serum IgM antibodies do not increase highly after infection, there are some differences between individuals.

Two cases of measles after vaccination with measles mumps and rubella combined live attenuated vaccine / 上海预防医学

Measles is an acute respiratory infectious disease caused by the measles virus. It is highly infectious and easy to occur in children. It causes many serious complications such as tracheitis， otitis media and pneumonia. Since the promotion of the measles vaccine in China， the measles epidemic has been effectively controlled. From June 1， 2020， the immunization procedure of measles-containing vaccine for children in Shanghai has been adjusted to one dose of measles， mumps and rubella combined live attenuated vaccine （MMR） at the age of 8 months， 18 months and 6 years. There is generally no local reaction after the injection of the MMR vaccine. A few individuals may have transient fever and scattered rash， which generally fade away by themselves. However， because it is a live vaccine， it may cause vaccine related diseases in extremely rare cases. This paper reports two cases of measles after vaccination with the MMR vaccine.