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1.
Front Immunol ; 13: 911738, 2022.
Article in English | MEDLINE | ID: covidwho-2198836

ABSTRACT

Introduction: Vaccination is an effective strategy for preventing SARS-CoV-2 infection and associated mortality. Renal Transplant Recipients (RTRs) are vulnerable to acquiring infection and high mortality due to their immunocompromised state. Varying responses to the different vaccines, depending on types of vaccines and population, have been reported. Vaccines supply is also limited. The current study evaluated the seroconversion rate after SARS-CoV-2 infection and 2 doses of either COVAXIN™ or COVISHIELD™ vaccination in RTR. Methods: The serum anti-SARS-CoV-2 spike protein neutralizing antibody titer was measured in 370 RTRs who acquired SARS-CoV-2 infection (n=172), yet not vaccinated; and those vaccinated with COVAXIN™ (n=78), and COVISHIELD™ (n=120) by chemiluminescence microparticle immunoassay methods from serum. Result: Overall, the seroconversion rate either after vaccination or infection was 85.13% (315/370). The vaccine-associated seroconversion was 80.30% (159/198). SARS-CoV-2 infection-associated seroconversion was 90.69% (156/172), COVISHIELD™ associated seroconversion was 79.2% (95/120), and COVAXIN™ associated seroconversion was 82.05% (64/78). The median IgG titer in the SARS-CoV-2 infection group was 646.50 AU/ml (IQR: 232.52-1717.42), in the COVAXIN™ group was 1449.75 AU/ml (IQR: 400.0-3068.55), and the COVISHIELD™ vaccination group was 1500.51 AU/ml (IQR: 379.47-4938.50). The seroconversion rate and antibody titers were similar irrespective of the place of sampling. Patient's age-associated seroconversion in <45 years was 88.01% (213/242), 45.1-60 years was 83.18% (94/113), and > 60 years was 58.3% (7/12). Conclusions: Both infection and vaccination induce robust antibody formation in RTRs. The seroconversion rate after SARS-CoV-2 infection was higher but with a lower antibody titer than vaccines. The vaccines, COVAXIN™ and COVISHIELD™, induce more elevated antibody titers than natural infection. The seroconversion rate and antibody titer in Indian RTRs appears to be better than in the western population, irrespective of their vaccination status.


Subject(s)
COVID-19 , Kidney Transplantation , Allografts , COVID-19/prevention & control , COVID-19 Vaccines , Humans , Immunoglobulin G , Middle Aged , SARS-CoV-2 , Seroconversion , Tertiary Care Centers , Vaccination , Vaccines, Inactivated
2.
Indian J Public Health ; 66(Supplement): S71-S75, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-2144166

ABSTRACT

Background: Persons with type 2 diabetes mellitus (T2DM) are at high-risk for COVID-19 infection and are a priority group for vaccination. Objectives: The objective of this study is to estimate the seroconversion and determine the side effects after COVID-19 vaccination among persons with T2DM in urban, rural, and tribal areas in Kerala. Methods: A cross-sectional study was conducted in urban, rural, and tribal field practice areas of a medical college in Central Kerala, among 396 persons with T2DM. The participants were selected by simple random sampling from the 200-250 diabetic patients visiting each health center. Qualitative and quantitative estimation of antibodies were done by WANTAI Ab enzyme-linked immunosorbent assay kit and Abbott SARS COV-2 IgG Quantitative assay, respectively. Results: The mean age of the respondents was 59.40 ± 12.25 years. A majority (65.5%) had received both doses of vaccine. About half (51.5%) experienced side effects after vaccination. Antibodies (IgG or IgM) were detected in 93.2% (95% confidence interval [CI] 90.2, 95.5) of participants. Those with a duration of diabetes ≥5 years, with a single dose of vaccine, were five times (adjusted odds ratio [aOR] - 5.23,95% CI 1.86, 14.66) and four times (aOR - 4.11, 95% CI 1.66, 10.13) more likely, respectively, to be seronegative. Those who took medication for diabetes were protected against a no antibody (aOR - 0.05, 95% CI 0.02, 0.148) response. The median antibody titer in a subset (150) of participants was 365.2 (90-1587) AU/ml. Past COVID infection was an independent determinant of high IgG titers (aOR - 4.95, 95% CI 1.50, 16.36). Conclusion: Reinforcing the importance of vaccination particularly among those with longer duration of diabetes is imperative.


Subject(s)
COVID-19 , Diabetes Mellitus, Type 2 , Humans , Middle Aged , Aged , Diabetes Mellitus, Type 2/epidemiology , India/epidemiology , Seroconversion , Cross-Sectional Studies , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Vaccination , Immunoglobulin G
3.
Front Immunol ; 13: 919762, 2022.
Article in English | MEDLINE | ID: covidwho-2141938

ABSTRACT

Objectives: We aimed to study the outcomes, severity, and seroconversion post SARS-CoV-2 infection in immunocompromised children and adolescents treated at our center. Method: For this observational study, all pediatric patients who had COVID-19 infection from Sep-22-2020 to Nov-10-2021were identified by reviewing our laboratory records. Their charts were reviewed to determine clinical severity and outcome. Blood samples were drawn for anti-SARS-CoV-2 antibody assay. Serious COVID-19 infection (SVI) was defined if the patient had moderate, severe, or critical illness. A cutoff of 100 U/mL anti-SARS-CoV-2 antibodies was used to categorize low and high titer seroconversion. Results: We identified 263 pediatric patients with COVID-19; most (68%) were symptomatic: 5% had severe or critical infection, 25% were hospitalized, 12 required respiratory support, 12 were admitted to the ICU, and five patients (2%) died. Multivariable analysis revealed several factors that predict SVI: Age above 12 years (p=0.035), body mass index above 95th percentile (p=0.034), comorbid conditions (p=0.025), absolute neutrophil count ≤500(p=0.014) and absolute lymphocyte count ≤300 (p=0.022). Levels of anti-SARS-CoV-2 spike antibodies were obtained for 173 patients at a median of 94 days (range, 14-300) after PCR diagnosis; of them 142 (82%) patients seroconverted; the lowest seroconversion rate was observed in patients with hematological malignancies (79%). Our univariable model showed that the following factors were predictive of low titer: lower ANC, p=0.01; hematologic malignancy, p=0.023; receiving steroids in the last 14 days, p=0.032; time since last chemotherapy or immunosuppressive therapy less than 30 days, p=0.002; and being on active chemotherapy in the last 3 months prior to infection, p<0.001. Conclusions: SARS-CoV-2 antibodies developed in most immunocompromised patients with COVID-19 infection in our study. Mortality was relatively low in our patients. Our univariable and multivariable models showed multiple variables that predict severity of infections and antibody response post COVID-19 infection. These observations may guide choice of active therapy during infection and the best timing of vaccination in this high-risk population.


Subject(s)
COVID-19 , Hematologic Neoplasms , Adolescent , Antibodies, Viral , Child , Humans , Immunocompromised Host , SARS-CoV-2 , Seroconversion
4.
Clin Immunol ; 245: 109144, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-2122391

ABSTRACT

Rituximab (RTX) is a very effective treatment for autoimmune rheumatic diseases (AIRD), but it increases infection risk and impairs vaccine responses. Herein we evaluated the antibody response of RTX-treated patients to the supplemental COVID-19 vaccine. After the supplemental dose, 53.1% of patients had detectable antibody titers. Only 36% of patients who did not mount an antibody response after the original vaccine series did have detectable antibodies after the supplemental dose (seroconversion). Patients with undetectable CD20+ cell levels did not seroconvert while hypogammaglobulinemia was associated with a 15-times decrease in the likelihood of seroconversion. Although we noted 11 COVID-19 infections after the supplemental dose, no patients who received monoclonal antibodies pre-exposure prophylaxis had COVID-19 afterwards. We propose that patients receiving RTX should continue to be prioritized for prophylaxis measures and that vaccination should be timed after B cell recovery wherever possible.


Subject(s)
Autoimmune Diseases , COVID-19 , Humans , Rituximab/therapeutic use , Seroconversion , COVID-19 Vaccines , COVID-19/drug therapy , COVID-19/prevention & control , SARS-CoV-2 , Vaccination , Antibodies, Viral/therapeutic use
5.
Int J Infect Dis ; 124: 212-223, 2022 Nov.
Article in English | MEDLINE | ID: covidwho-2113251

ABSTRACT

OBJECTIVES: Available data show that COVID-19 vaccines may be less effective in people living with HIV (PLWH) who are at increased risk for severe COVID-19. This meta-analysis aimed to compare the immunogenicity and efficacy of COVID-19 vaccines in PLWH with healthy individuals. METHODS: Pubmed/Medline, EMBASE, and the Cochrane Library were searched. Risk ratios of seroconversion were separately pooled using random-effects meta-analysis, and a systematic review without meta-analysis of SARS-CoV-2 antibody titer levels was performed after the first and second doses of a COVID-19 vaccine. RESULTS: A total of 22 studies with 6522 subjects met the inclusion criteria. After the first vaccine dose, seroconversion in PLWH was comparable to that in healthy individuals. After a second dose, seroconversion was slightly lower in PLWH compared with healthy controls, and antibody titers did not seem to be significantly affected or reduced among participants of both groups. CONCLUSION: COVID-19 vaccines show favorable immunogenicity and efficacy in PLWH. A second dose is associated with consistently improved seroconversion, although it is slightly lower in PLWH than in healthy individuals. Additional strategies, such as a booster vaccination with messenger RNA COVID-19 vaccines, might improve seroprotection for these patients.


Subject(s)
COVID-19 , HIV Infections , Humans , COVID-19 Vaccines , COVID-19/prevention & control , SARS-CoV-2 , Seroconversion , Antibodies, Viral , Vaccination
7.
Front Public Health ; 10: 974848, 2022.
Article in English | MEDLINE | ID: covidwho-2099265

ABSTRACT

Background: The coronavirus disease (COVID-19) pandemic, which has been ongoing for more than 2 years, has become one of the largest public health issues. Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is one of the most important interventions to mitigate the COVID-19 pandemic. Our objective is to investigate the relationship between vaccination status and time to seroconversion. Methods: We conducted a cross-sectional observational study during the SARS-CoV-2 B.1.617.2 outbreak in Jiangsu, China. Participants who infected with the B.1.617.2 variant were enrolled. Cognitive performance, quality of life, emotional state, chest computed tomography (CT) score and seroconversion time were evaluated for each participant. Statistical analyses were performed using one-way ANOVA, univariate and multivariate regression analyses, Pearson correlation, and mediation analysis. Results: A total of 91 patients were included in the analysis, of whom 37.3, 25.3, and 37.3% were unvaccinated, partially vaccinated, and fully vaccinated, respectively. Quality of life was impaired in 30.7% of patients, especially for mental component summary (MCS) score. Vaccination status, subjective cognitive decline, and depression were risk factors for quality-of-life impairment. The chest CT score mediated the relationship of vaccination status with the MCS score, and the MCS score mediated the relationship of the chest CT score with time to seroconversion. Conclusion: Full immunization course with an inactivated vaccine effectively lowered the chest CT score and improved quality of life in hospitalized patients. Vaccination status could influence time to seroconversion by affecting CT score and MCS score indirectly. Our study emphasizes the importance of continuous efforts in encouraging a full vaccination course.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Pandemics , COVID-19 Vaccines , Seroconversion , COVID-19/prevention & control , Mental Health , Cross-Sectional Studies , Quality of Life , Tomography, X-Ray Computed , Vaccination
8.
Indian J Med Res ; 155(5&6): 499-504, 2022.
Article in English | MEDLINE | ID: covidwho-2055696

ABSTRACT

Background & objectives: Vaccination against COVID-19 induces spike protein-binding IgG antibodies, a robust correlate of protection against COVID-19. This study was undertaken to assess the humoral response after completion of both the doses of ChAdOx1 nCoV vaccine in healthcare workers (HCWs) at a tertiary care health centre in India. Methods: A cross-sectional COVID-19 vaccine-induced antibody study was conducted among HCWs. IgG antibodies against spike protein were measured at least 28 days after the first dose and the second dose of vaccination in both SARS CoV-2 naïve and recovered HCWs. Mean and median antibody titre following each dose of vaccine and its association with age, gender, co-morbidities and factors such as exercise, stress and sleep deprivation were also explored. Results: Among the 200 vaccine recipients, 91.5 per cent showed seroconversion after the first dose and 99.5 per cent after the second dose. The mean titre after the second dose was significantly higher when compared to the first dose (12.68±4.17 vs. 9.83±6.3, P=0.001). More than half (54%) had high antibody titre ≥12 S/Co (Signal/cut-off). Previous COVID-19 infection was the single most important factor influencing antibody production, where the mean titre just after a single dose [mean-17.81±5.94, median-20.5 (interquartile range [IQR]-3.7)] surpassed the titre after the second dose in SARS CoV-2 naïve individuals [mean-12.29±4.00, median-12.8 (IQR-3.7), P=0.001]. Furthermore, 28 per cent of vaccinees showed a reduction in titre after the second dose. The mean fall in titre was 2.25±1.40 and was more pronounced in males, the younger age group and those with previous COVID-19 infection. Interpretation & conclusions: ChAdOx1 nCov-19 vaccine after two doses elicited an excellent immune response. However, greater immunogenicity after the first dose was seen among those with previous COVID-19 infection, even surpassing the titre achieved by the second dose of vaccine in SARS CoV-2 naïve recipients. A fall in antibody titre after the second dose is a matter of concern and requires further studies.


Subject(s)
COVID-19 , Viral Vaccines , Male , Humans , COVID-19 Vaccines , ChAdOx1 nCoV-19 , Seroconversion , COVID-19/epidemiology , COVID-19/prevention & control , Spike Glycoprotein, Coronavirus , Cross-Sectional Studies , Antibodies, Viral , SARS-CoV-2 , Immunoglobulin G , Vaccination
9.
Virol J ; 19(1): 132, 2022 08 08.
Article in English | MEDLINE | ID: covidwho-2053924

ABSTRACT

BACKGROUND: Immunocompromised (IC) patients are at higher risk of more severe COVID-19 infections than the general population. Special considerations should be dedicated to such patients. We aimed to investigate the efficacy of COVID-19 vaccines based on the vaccine type and etiology as well as the necessity of booster dose in this high-risk population. MATERIALS AND METHODS: We searched PubMed, Web of Science, and Scopus databases for observational studies published between June 1st, 2020, and September 1st, 2021, which investigated the seroconversion after COVID-19 vaccine administration in adult patients with IC conditions. For investigation of sources of heterogeneity, subgroup analysis and sensitivity analysis were conducted. Statistical analysis was performed using R software. RESULTS: According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, we included 81 articles in the meta-analysis. The overall crude prevalence of seroconversion after the first (n: 7460), second (n: 13,181), and third (n: 909, all population were transplant patients with mRNA vaccine administration) dose administration was 26.17% (95% CI 19.01%, 33.99%, I2 = 97.1%), 57.11% (95% CI: 49.22%, 64.83%, I2 = 98.4%), and 48.65% (95% CI: 34.63%, 62.79%, I2 = 94.4%). Despite the relatively same immunogenicity of mRNA and vector-based vaccines after the first dose, the mRNA vaccines induced higher immunity after the second dose. Regarding the etiologic factor, transplant patients were less likely to develop immunity after both first and second dose rather than patients with malignancy (17.0% vs 37.0% after first dose, P = 0.02; 38.3% vs 72.1% after second dose, P < 0.001) or autoimmune disease (17.0% vs 36.4%, P = 0.04; 38.3% vs 80.2%, P < 0.001). To evaluate the efficacy of the third dose, we observed an increasing trend in transplant patients after the first (17.0%), second (38.3%), and third (48.6%) dose. CONCLUSION: The rising pattern of seroconversion after boosting tends to be promising. In this case, more attention should be devoted to transplant patients who possess the lowest response rate.


Subject(s)
COVID-19 Vaccines , COVID-19 , Adult , Antibodies, Viral , COVID-19/prevention & control , Humans , SARS-CoV-2 , Seroconversion , Vaccination , Vaccines, Synthetic , mRNA Vaccines
10.
Euro Surveill ; 27(37)2022 09.
Article in English | MEDLINE | ID: covidwho-2039627

ABSTRACT

IntroductionSocio-economic and ethnic background have been discussed as possible risk factors for SARS-CoV-2 infections in children. Improved knowledge could lead to tailored prevention strategies and help improve infection control.AimWe aimed to identify risk factors for SARS-CoV-2 infections in children in the first and second wave of the pandemic.MethodsWe performed an observational population-based cohort study in children (6 months-18 years) scheduled for legally required preventive examination and their parents in a metropolitan region in Germany. Primary endpoint was the SARS-CoV-2 seroconversion rate during the study period. Risk factors assessed included age, pre-existing medical conditions, socio-economic factors and ethnicity.ResultsWe included 2,124 children and their parents. Seroconversion rates among children in all age groups increased 3-4-fold from June 2020 to February 2021. Only 24 of 58 (41%) seropositive children reported symptoms. In 51% of infected children, at least one parent was also SARS-CoV-2-positive. Low level of parental education (OR = 3.13; 95% CI: 0.72-13.69) non-significantly increased the risk of infection. Of the total cohort, 38.5% had a migration background, 9% of Turkish and 5% of Middle Eastern origin, and had the highest risk for SARS-CoV-2 infections (OR = 6.24; 95% CI: 1.38-28.12 and OR = 6.44 (95% CI: 1.14-36.45) after adjustment for other risk factors.ConclusionIn the second half of 2020, seroprevalence for SARS-CoV-2 in children increased especially in families with lower-socioeconomic status. Culture-sensitive approaches are essential to limit transmission and could serve as a blueprint for vaccination strategies.


Subject(s)
COVID-19 , COVID-19/epidemiology , Child , Cohort Studies , Ethnicity , Germany/epidemiology , Humans , Risk Factors , SARS-CoV-2 , Seroconversion , Seroepidemiologic Studies , Socioeconomic Factors
11.
PLoS One ; 17(9): e0274484, 2022.
Article in English | MEDLINE | ID: covidwho-2039417

ABSTRACT

This study aimed to determine the cumulative incidence, prevalence, and seroconversion of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and its associated factors among healthcare workers (HCWs) of a University Hospital in Bogotá, Colombia. An ambispective cohort was established from March 2020 to February 2021. From November 2020 to February 2021, SARS-CoV-2 antibodies were measured on two occasions 14-90 days apart to determine seroprevalence and seroconversion. We used multivariate log-binomial regression to evaluate factors associated with SARS-CoV-2 infection. Among 2,597 HCWs, the cumulative incidence of infection was 35.7%, and seroprevalence was 21.5%. A reduced risk of infection was observed among those aged 35-44 and ≥45 years (adjusted relative risks [aRRs], 0.84 and 0.83, respectively), physicians (aRR, 0.77), those wearing N95 respirators (aRR, 0.82) and working remotely (aRR, 0.74). Being overweight (aRR, 1.18) or obese (aRR, 1.24); being a nurse or nurse assistant (aRR, 1.20); working in the emergency room (aRR, 1.45), general wards (aRR, 1.45), intensive care unit (aRR, 1.34), or COVID-19 areas (aRR, 1.17); and close contact with COVID-19 cases (aRR, 1.47) increased the risk of infection. The incidence of SARS-CoV-2 infection found in this study reflects the dynamics of the first year of the pandemic in Bogotá. A high burden of infection calls for strengthening prevention and screening measures for HCWs, focusing especially on those at high risk.


Subject(s)
COVID-19 , COVID-19/epidemiology , Colombia/epidemiology , Health Personnel , Hospitals, University , Humans , Incidence , Prevalence , SARS-CoV-2 , Seroconversion , Seroepidemiologic Studies
12.
Vaccine ; 40(42): 6133-6140, 2022 10 06.
Article in English | MEDLINE | ID: covidwho-2031731

ABSTRACT

Well-regulated clinical trials have shown FDA-approved COVID-19 vaccines to be immunogenic and highly efficacious. We evaluated seroconversion rates in adults reporting ≥ 1 dose of an mRNA COVID-19 vaccine in a cohort study of nearly 8000 adults residing in North Carolina to validate immunogenicity using a novel approach: at-home, participant administered point-of-care testing. Overall, 91.4% had documented seroconversion within 75 days of first vaccination (median: 31 days). Participants who were older and male participants were less likely to seroconvert (adults aged 41-65: adjusted hazard ratio [aHR] 0.69 [95% confidence interval (CI): 0.64, 0.73], adults aged 66-95: aHR 0.55 [95% CI: 0.50, 0.60], compared to those 18-40; males: aHR 0.92 [95% CI: 0.87, 0.98], compared to females). Participants with evidence of prior infection were more likely to seroconvert than those without (aHR 1.50 [95% CI: 1.19, 1.88]) and those receiving BNT162b2 were less likely to seroconvert compared to those receiving mRNA-1273 (aHR 0.84 [95% CI: 0.79, 0.90]). Reporting at least one new symptom after first vaccination did not affect time to seroconversion, but participants reporting at least one new symptom after second vaccination were more likely to seroconvert (aHR 1.11 [95% CI: 1.05, 1.17]). This data demonstrates the high community-level immunogenicity of COVID-19 vaccines, albeit with notable differences in older adults, and feasibility of using at-home, participant administered point-of-care testing for community cohort monitoring. Trial registration: ClinicalTrials.gov NCT04342884.


Subject(s)
COVID-19 , Vaccines , Aged , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , Cohort Studies , Female , Humans , Immunogenicity, Vaccine , Male , North Carolina/epidemiology , RNA, Messenger , Seroconversion
13.
Biosens Bioelectron ; 217: 114710, 2022 Dec 01.
Article in English | MEDLINE | ID: covidwho-2031160

ABSTRACT

COVID-19 is still unfolding, while many people have been vaccinated. In comparison to nucleic acid testing (NAT), antibody-based immunoassays are faster and more convenient. However, its application has been hampered by its lower sensitivity and the existing fact that by traditional immunoassays, the measurable seroconversion time of pathogen-specific antibodies, such as IgM or IgG, lags far behind that of nucleic acids. Herein, by combining the single molecule array platform (Simoa), RBD, and a previously identified SARS-CoV-2 S2 protein derivatized 12-aa peptide (S2-78), we developed and optimized an ultrasensitive assay (UIM-COVID-19 assay). Sera collected from three sources were tested, i.e., convalescents, inactivated virus vaccine-immunized donors and wild-type authentic SARS-CoV-2-infected rhesus monkeys. The sensitivities of UIM-COVID-19 assays are 100-10,000 times higher than those of conventional flow cytometry, which is a relatively sensitive detection method at present. For the established UIM-COVID-19 assay using RBD as a probe, the IgG and IgM seroconversion times after vaccination were 7.5 and 8.6 days vs. 21.4 and 24 days for the flow cytometry assay, respectively. In addition, using S2-78 as a probe, the UIM-COVID-19 assay could differentiate COVID-19 patients (convalescents) from healthy people and patients with other diseases, with AUCs ranging from 0.85-0.95. In summary, the UIM-COVID-19 we developed here is a promising ultrasensitive biodetection strategy that has the potential to be applied for both immunological studies and diagnostics.


Subject(s)
Biosensing Techniques , COVID-19 , Nucleic Acids , Vaccines , Antibodies, Viral , Antibody Formation , COVID-19/diagnosis , Humans , Immunoglobulin G , Immunoglobulin M , SARS-CoV-2 , Sensitivity and Specificity , Seroconversion
14.
Immunol Lett ; 250: 1-6, 2022 10.
Article in English | MEDLINE | ID: covidwho-2028118

ABSTRACT

Antibody testing after COVID-19 vaccination is generally not recommended. Here, we present the results of a retrospective study, in which we analyzed antibody levels before and after the first dose of the ChAdOx1 vector vaccine. We identified 5% non-responders (43.6 ± 10.6 years; females: 41%) and 3.4% low-responders (44.2 ± 10.1 years; females: 64%) after the first dose. Of these, 61 individuals received a timely second dose either with a homologous (ChAdOx1/ChAdOx1) or heterologous (ChAdOx1/mRNA-1273) schedule. All vaccinees achieved positive S1-specific IgG titers to the ancestral SARS-CoV-2 strain after the second dose, but antibody levels as well as neutralization titers against the ancestral SARS-CoV-2 strain were higher after the heterologous schedule. However, Omicron-specific neutralizing antibodies were not detectable after two doses in either group, indicating that a third vaccine dose is needed to enhance cross-reactive antibodies against currently circulating and emerging variants of concern.


Subject(s)
COVID-19 Vaccines , COVID-19 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , Female , Humans , Immunoglobulin G , Retrospective Studies , SARS-CoV-2 , Seroconversion , Vaccination
15.
PLoS One ; 17(9): e0274095, 2022.
Article in English | MEDLINE | ID: covidwho-2021954

ABSTRACT

The immune response and specific antibody production in COVID-19 are among the key factors that determine both prognostics for individual patients and the global perspective for controlling the pandemics. So called "dark figure", that is, a part of population that has been infected but not registered by the health care system, make it difficult to estimate herd immunity and to predict pandemic trajectories. Here we present a follow up study of population screening for hidden herd immunity to SARS-CoV-2 in individuals who had never been positively diagnosed against SARS-CoV-2; the first screening was in May 2021, and the follow up in December 2021. We found that specific antibodies targeting SARS-CoV-2 detected in May as the "dark figure" cannot be considered important 7 months later due to their significant drop. On the other hand, among participants who at the first screening were negative for anti-SARS-CoV-2 IgG, and who have never been diagnosed for SARS-CoV-2 infection nor vaccinated, 26% were found positive for anti-SARS-CoV-2 IgG. This can be attributed to of the "dark figure" of the recent, fourth wave of the pandemic that occurred in Poland shortly before the study in December. Participants who were vaccinated between May and December demonstrated however higher levels of antibodies, than those who undergone mild or asymptomatic (thus unregistered) infection. Only 7% of these vaccinated participants demonstrated antibodies that resulted from infection (anti-NCP). The highest levels of protection were observed in the group that had been infected with SARS-CoV-2 before May 2021 and also fully vaccinated between May and December. These observations demonstrate that the hidden fraction of herd immunity is considerable, however its potential to suppress the pandemics is limited, highlighting the key role of vaccinations.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral , COVID-19/epidemiology , Follow-Up Studies , Humans , Immunoglobulin G , Seroconversion
17.
PLoS One ; 17(8): e0272690, 2022.
Article in English | MEDLINE | ID: covidwho-1993492

ABSTRACT

The long-term antibody response to the novel SARS-CoV-2 in infected patients and their residential neighborhood remains unknown in Indonesia. This information will provide insights into the antibody kinetics over a relatively long period as well as transmission risk factors in the community. We aim to prospectively observe and determine the kinetics of the anti-SARS-CoV-2 antibody for 2 years after infection in relation to disease severity and to determine the risk and protective factors of SARS CoV-2 infections in the community. A cohort of RT-PCR confirmed SARS-CoV-2 patients (case) will be prospectively followed for 2 years and will be compared to a control population. The control group comprises SARS-CoV-2 non-infected people who live within a one-kilometer radius from the corresponding case (location matching). This study will recruit at least 165 patients and 495 controls. Demographics, community variables, behavioral characteristics, and relevant clinical data will be collected. Serum samples taken at various time points will be tested for IgM anti-Spike protein of SARS-CoV-2 and IgG anti-Spike RBD of SARS-CoV-2 by using Chemiluminescent Microparticle Immunoassay (CMIA) method. The Kaplan-Meier method will be used to calculate cumulative seroconversion rates, and their association with disease severity will be estimated by logistic regression. The risk and protective factors associated with the SARS-CoV-2 infection will be determined using conditional (matched) logistic regression and presented as an odds ratio and 95% confidence interval.


Subject(s)
COVID-19 , Antibodies, Viral , Antibody Formation , Humans , SARS-CoV-2 , Seroconversion
18.
AIDS ; 36(11): 1545-1552, 2022 Sep 01.
Article in English | MEDLINE | ID: covidwho-1992434

ABSTRACT

OBJECTIVES: To assess humoral responses to SARS-CoV-2 Delta-variant in people with HIV (PWH) after BNT162b2-vaccination. DESIGN: Multicenter cohort study of PWH with CD4 + cell count less than 500 cells/µl and viral load less than 50 copies/ml on stable antiretroviral therapy for at least 3 months. METHODS: Anti-SARS-CoV-2 receptor-binding-domain IgG antibodies (anti-RBD IgG) were quantified and neutralization capacity was evaluated by ELISA/GenScript and virus-neutralization-test against the D614G-strain, beta and delta variants before vaccination (day 0) and 1 month after complete schedule (M1). RESULTS: We enrolled 97 PWH, 85 received two vaccine shots. The seroconversion rate for anti-RBD IgG was 97% [95% confidence interval (CI) 90-100%] at M1. Median (IQR) anti-RBD IgG titer was 0.97 (0.97-5.3) BAU/ml at D0 and 1219 (602-1929) at M1. Neutralization capacity improved between D0 (15%; 50% CI 8-23%) and M1 (94%; 95% CI 87-98%) ( P  < 0.0001). At M1, NAbs against the D614G strain, beta and delta variants were present in 82, 77, and 84% PWH, respectively. The seroconversion rate and median anti-RBD-IgG level were 91% and 852 BAU/ml, respectively, in PWH with CD4 + cell count less than 250 ( n  = 13) and 98% and 1270 BAU/ml for CD4 + greater than 250 ( n  = 64) ( P  = 0.3994). NAbs were present in 73% of PWH with CD4 + less than 250 and 97% of those with CD4 + cell count greater than 250 ( P  = 0.0130). NAbs against beta variant were elicited in 50% in PWH with CD4 + cell count less than 250 and in 81% of those with CD4 + cell count greater than 250 ( P  = 0.0292). CD4 + and CD8 + T-cell counts were unchanged, whereas CD19 + B-cell counts decreased after vaccination(208 ±â€Š124 at D0 vs. 188 ±â€Š112 at M1, P  < 0.01). No notable adverse effects or COVID-19 cases were reported. CONCLUSION: Seroconversion rates were high, with delta-neutralization rates similar to those for the D61G strain, after a two-dose BNT162b2 vaccination in PWH.


Subject(s)
COVID-19 , HIV Infections , Antibodies, Viral , BNT162 Vaccine , COVID-19/prevention & control , Cohort Studies , Humans , Immunoglobulin G , SARS-CoV-2 , Seroconversion , Vaccination
19.
Proc Natl Acad Sci U S A ; 119(34): e2201541119, 2022 08 23.
Article in English | MEDLINE | ID: covidwho-1984598

ABSTRACT

Whereas pathogen-specific T and B cells are a primary focus of interest during infectious disease, we have used COVID-19 to ask whether their emergence comes at a cost of broader B cell and T cell repertoire disruption. We applied a genomic DNA-based approach to concurrently study the immunoglobulin-heavy (IGH) and T cell receptor (TCR) ß and δ chain loci of 95 individuals. Our approach detected anticipated repertoire focusing for the IGH repertoire, including expansions of clusters of related sequences temporally aligned with SARS-CoV-2-specific seroconversion, and enrichment of some shared SARS-CoV-2-associated sequences. No significant age-related or disease severity-related deficiencies were noted for the IGH repertoire. By contrast, whereas focusing occurred at the TCRß and TCRδ loci, including some TCRß sequence-sharing, disruptive repertoire narrowing was almost entirely limited to many patients aged older than 50 y. By temporarily reducing T cell diversity and by risking expansions of nonbeneficial T cells, these traits may constitute an age-related risk factor for COVID-19, including a vulnerability to new variants for which T cells may provide key protection.


Subject(s)
Adaptive Immunity , COVID-19 , Immunoglobulin Heavy Chains , Receptors, Antigen, T-Cell, alpha-beta , Receptors, Antigen, T-Cell , SARS-CoV-2 , Adaptive Immunity/genetics , Aged , B-Lymphocytes/immunology , COVID-19/genetics , COVID-19/immunology , Genetic Loci , Humans , Immunoglobulin Heavy Chains/genetics , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell, alpha-beta/genetics , SARS-CoV-2/immunology , Seroconversion , T-Lymphocytes/immunology
20.
Obes Facts ; 15(5): 648-654, 2022.
Article in English | MEDLINE | ID: covidwho-1973982

ABSTRACT

INTRODUCTION: The aim of this study was to investigate the antibody titers against SARS-CoV-2 spike antigens and the risk factors affecting antibody levels in people living with obesity (PwO) after inactive SARS-CoV-2 vaccine (CoronaVac) administration. METHODS: 169 consecutive patients with obesity who visited the Center for Obesity Management at Istanbul University-Cerrahpasa, Cerrahpasa Medical Faculty Hospitals, between May and August 2021, were invited to the study. The nonobese control group was recruited from 191 subjects who visited the Cerrahpasa Hospitals Vaccination Unit. The study group and the nonobese control group have already received two doses of inactive SARS-CoV-2 vaccine. The SARS-CoV-2 IgG nucleocapsid antibody test was administered to patients and control subjects to discover those who had prior SARS-CoV-2 infection. Forty-one patients who had prior infection and received two doses of vaccine were also included in the study as a subgroup. Blood samples were taken on the 3rd to 4th week after the second vaccination. SARS-CoV-2 IgG antibody titers were determined by quantitative serological methods. RESULTS: Antibody titers against SARS-CoV-2 spike antigen of individuals with BMI ≥30.0 kg/m2 were significantly lower than those with BMI <30 kg/m2 (p = 0.001) in the study group. Moreover, the antibody titers in people with BMI ≥30.0 kg/m2 were significantly lower than in those having a BMI <30.0 kg/m2 in the subgroup (p = 0.03). Age (p = 0.03), BMI (p = 0.006), and hypertension (p = 0.03) were found to be independent risk factors for antibody response in PwO. Women with non-prior SARS-CoV-2 infection showed a significantly higher antibody response then men (p = 0.001). CONCLUSION: SARS-CoV-2-Immunoglobulin G antibody levels against inactive (CoronaVac) vaccine were found to be lower in PwO compared to nonobese individuals. Antibody titers may be measured, and booster doses should be delivered accordingly in PwO for optimal protection.


Subject(s)
COVID-19 , Vaccines , Male , Humans , Female , Seroconversion , COVID-19 Vaccines , SARS-CoV-2 , COVID-19/prevention & control , Antibodies, Viral , Immunoglobulin G , Vaccination , Risk Factors , Obesity
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