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933 result(s) for "Plasma donor"
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mRNA Vaccines Enhance Neutralizing Immunity against SARS-CoV-2 Variants in Convalescent and ChAdOx1-Primed Subjects
To identify the most efficient methods of immunological protection against SARS-CoV-2, including the currently most widespread variants of concern (VOCs)—B.1.1.7, B.1.351 and P.1—a simultaneous side-by-side-comparison of available vaccination regimes is required. In this observational cohort study, we compared immunological responses in 144 individuals vaccinated with the mRNA vaccines BNT162b2 or mRNA-1273 and the vector vaccine ChAdOx1-nCoV-19, either alone, in combination, or in the context of COVID-19-convalescence. Unvaccinated COVID-19-convalescent subjects served as a reference. We found that cellular and serological immune responses, including neutralizing capacity against VOCs, were significantly stronger with mRNA vaccines as compared with COVID-19-convalescent individuals or vaccinated individuals receiving the vector vaccine ChAdOx1-nCoV-19. Booster immunizations with mRNA vaccines triggered strong and broadly neutralizing antibody and IFN-γ responses in 100% of vaccinated individuals investigated. This effect was particularly strong in COVID-19-convalescent and ChAdOx1-nCoV-19-primed individuals, who were characterized by comparably moderate cellular and neutralizing antibody responses before mRNA vaccine booster. Heterologous vaccination regimes and convalescent booster regimes using mRNA vaccines may allow enhanced protection against SARS-CoV-2, including current VOCs. Furthermore, such regimes may facilitate rapid (re-)qualification of convalescent plasma donors with high titers of broadly neutralizing antibodies.
Hepatitis A Virus Incidence Rates and Biomarker Dynamics for Plasma Donors, United States
The United States is currently affected by widespread hepatitis A virus (HAV) outbreaks. We investigated HAV incidence rates among source plasma donors in the United States since 2016. Serial donations from HAV-positive frequent donors were analyzed for common biologic markers to obtain a detailed picture of the course of infection. We found a considerable increase in incidence rates with shifting outbreak hotspots over time. Although individual biomarker profiles were highly variable, HAV RNA typically had a high peak and a biphasic decrease and often remained detectable for several months. One donor had a biomarker pattern indicative of previous exposure. Our findings show that current HAV outbreaks have been spilling over into the plasma donor population. The detailed results presented improve our comprehension of HAV infection and related public health aspects. In addition, the capture of full RNA curves enables estimation of HAV doubling time.
HIV-related stigma among people living with HIV/AIDS in rural Central China
Background HIV-related stigma among people living with HIV/AIDS (PLWHA) has been associated with many negative consequences, including poor adherence to therapy and undue psychological stress. However, the relative influence of specific demographic and situational factors contributing to HIV-related stigma among rural PLWHA in central China remains unknown. The aim of this study was to explore the level of HIV-related stigma among rural PLWHA across specific demographic and situational factors in central China. Methods A cross-sectional study was conducted among PLWHA receiving care through the Chinese Centers for Disease Control of Zhenping county in Henan Province, China. Participants completed a 55-item questionnaire which included demographic and disease-related factors, HIV-related stigma was measured utilizing the validated Berger HIV Stigma Scale which has good psychometric characteristics in Chinese PLWHA. Results A total of 239 PLWHA completed the survey. The mean total HIV-related stigma score was 105.92 (SD = 12.35, 95% CI: 104.34, 107.49). Multivariable linear regression analysis revealed a higher level of HIV-related stigma in younger PLWHA (β = − 0.57, 95% CI = − 0.78,-0.35, p<0.001) and those who self-reported opportunistic infections (β = 6.26, 95% CI = 1.26, 11.26, p < 0.05). Conclusions The findings in the current study suggest that rural PLWHA in central China suffer from the burden of HIV-related stigma at a moderate to high level. Younger PLWHA and PLWHA that have opportunistic infections tend to perceive a higher level of HIV stigma.
Incidence of SARS-CoV-2 during the Omicron wave: Results of a longitudinal serosurvey in Québec, Canada
Objectives Conventional serological approaches lack sensitivity for the detection of recent SARS-CoV-2 infections in vaccinated individuals, as these individuals exhibit a blunted anti-nucleocapsid (N) response. This limitation was recently addressed by the development of a “ratio-based approach”, which compares longitudinally collected specimens. Here, we used this approach to estimate the incidence of SARS-CoV-2 infection and reinfection in Québec (Canada) during the Omicron wave. Methods Consenting plasma donors were included if they donated plasma before December 15, 2021 and during six consecutive periods of ~ 3 months between December 15, 2021 and July 7, 2023 (study period). Anti-N levels were measured with an enzyme-linked immunosorbent assay, and seroconversion was characterized by a ratio of ≥ 1.5 between the optical density of two consecutive samples. Results Among the 254 donors, the adjusted proportion of donors (95% confidence interval [CI]) with a new infection ranged between 18.1% (13.2‒23.0) and 24.2% (18.8‒29.7) over Periods 1–5 and fell to 7.9% (4.9‒11.0) during Period 6. During the study period, the proportion of newly infected donors decreased among those aged < 60 (Period 1 = 31.6%, Period 5 = 4.4%), but increased among those aged ≥ 70 (Period 1 = 0.3%, Period 6 = 10.3%). Throughout the study period, 72 (28.3%) reinfections occurred, including two seroconversion events in a single donor. Overall, 87.4% (95% CI = 82.7‒91.2) were infected by SARS-CoV-2 at least once during the study period. Conclusion The vast majority of the Québec population may have been infected during the Omicron wave. This longitudinal survey demonstrates the usefulness of the “ratio-based approach” for identifying both new infections and reinfections in a vaccinated population.
Analysis of influencing factors of serum total protein and serum calcium content in plasma donors
The adverse effects of plasma donation on the body has lowered the odds of donation. The aim of this study was to investigate the prevalence of abnormal serum calcium and total serum protein related to plasma donation, identify the influencing factors, and come up with suggestions to make plasma donation safer. Donors from 10 plasmapheresis centers in five provinces of China participated in this study. Serum samples were collected before donation. Serum calcium was measured by arsenazo III colorimetry, and the biuret method was used for total serum protein assay. An automatic biochemical analyzer was used to conduct serum calcium and total serum protein tests. The mean serum calcium was 2.3 ± 0.15 mmol/L and total serum protein was 67.75 ± 6.02 g/L. The proportions of plasma donors whose serum calcium and total serum protein were lower than normal were 20.55% (815/3,966) and 27.99% (1,111/3,969), respectively. There were significant differences in mean serum calcium and total serum protein of plasma donors with different plasma donation frequencies, gender, age, regions, and body mass index (BMI), (all  < 0.05). Logistic regression analysis revealed that donation frequencies, age, BMI and regions were significantly associated with a higher risk of low serum calcium level, and donation frequencies, gender, age and regions were significant determinants factors of odds of abnormal total serum protein. Donation frequencies, gender, age, regions, and BMI showed different effects on serum calcium and total serum protein. More attention should be paid to the age, donation frequency and region of plasma donors to reduce the probability of low serum calcium and low total serum protein.
Behavioral verification and risk factors of HIV cross-population transmission in China: analysis of national surveillance data 1989–2022
Introduction The dynamic HIV/AIDS epidemic significantly impacts China, particularly affecting injection drug users (IDUs), former plasma donors (FPDs), men who have sex with men (MSM), and those engaging in high-risk heterosexual behavior (HRHB). This study specifically focuses on identifying the risk factors and influences that drive the spread of HIV among these population groups by performing a comprehensive analysis of contact histories of individuals diagnosed with HIV. Methods Data for this research were gathered from China’s HIV/AIDS Comprehensive Response Information Management System (CRIMS). Contact histories were described using bar and venn diagram. Trend in engaging in HBRB among MSM were identify potential change using the Cochran-Armitage test. Logistic regression was employed to analyze the factors influencing HBRB in MSM. Results From 1989 through to 2022, a total of 1,457,218 individuals aged 15 years or older in China, who reported being infected with HIV, indicated they had one or more types of contact histories including injecting drug use, male homosexual behavior, commercial plasma donation, and high-risk heterosexual behavior. Among these, 97.0% reported a single type of contact history, while 3.0% reported having multiple contact histories. Of those with multiple contact histories, 98.0% (42,258 individuals) had engaged in HRHB. Among all HIV-infected IDUs, MSM, and FPDs, their respective proportions of engagement in HRHB were 11.8%, 5.7% and 6.2%. Prior to 2012, most were reported to be IDUs; however, subsequent to this, most reported being MSM. Factors that heightened the risk of engaging in HRHB among HIV-infected MSM included being of age between 25–34 years [adjusted odds ratio ( AOR ) = 1.29] or 35–44 years ( AOR  = 1.22), marital status such as being married ( AOR  = 1.23) or being divorced/widowed ( AOR  = 1.17), belonging to an ethnic minority ( AOR  = 1.29), receiving diagnosis in hospitals ( AOR  = 1.81), residing in rural areas ( AOR  = 1.12), among others. However, the risk of HRHB decreased when age ≥ 55 years (55–64 years: AOR  = 0.82; ≥ 65 years: AOR  = 0.64). Conclusion The potential for HIV transmission among diverse populations is substantial. As such, it is imperative that strategies are implemented to mitigate the propagation of HIV to the general populace via heterosexual intercourse.
Parvovirus B19 DNA and antibodies in Chinese plasma donors, plasma pools and plasma derivatives
Human parvovirus B19 (B19V) is a common contaminant found in plasma pools and plasma derivatives. Previous studies were mainly focused on limited aspects, further assessment of prevalence of B19V DNA and antibodies in plasma donors, the contamination of B19V in pooled plasma and plasma derivatives should be performed in China. Individual plasma donors' samples from four provinces and pooled plasma from four Chinese blood product manufacturers were collected and screened using B19V DNA diagnostic kits between October 2018 and May 2020. The positive samples were investigated for the seroprevalence of B19V antibodies and subjected to sequence analysis and alignment for phylogenetic studies. Moreover, 11 plasma donors who were B19V DNA-positive at their first testing were also followed during the later donation period. Additionally, 400 plasma pools and 20 batches of plasma derivatives produced by pooled plasma with a viral load of B19V DNA exceeding 10 IU/mL were also collected and tested for B19V DNA and antibodies. To comprehensively and systematically determine the frequency and viral load of B19V DNA in plasma donors, pooled plasma, and plasma derivatives from four Chinese blood product manufacturers. A total of 17,187 plasma donors were analyzed and 44 (0.26%) specimens were found positive for B19V DNA. The quantitative DNA levels ranged from 1.01 × 10 to 5.09 × 10 IU/mL. Forty-four DNA-positive specimens were also investigated for the seroprevalence of B19V antibodies, 75.0% and 2.3% of which were seropositive for B19V IgG and IgM antibodies, respectively. The phylogenic analyses showed that the prevalent genotypes in the four provinces' plasma donors belonged to B19V Genotype 1. Eleven individual plasma donors who were B19V DNA-positive at the first donation were then followed for a period, and in general, the DNA levels of B19V gradually decreased. Moreover, 64.8% (259/400) of the pooled plasma was contaminated by B19V, with concentrations of 1.05 × 10 -3.36 × 10 IU/mL. Approximately 72.6% of the DNA-positive plasma pools were only moderately contaminated (<10 IU/mL), while 27.4% contained >10 IU/mL. Twenty batches of plasma derivatives produced by pooled plasma with a viral load of B19V DNA exceeding 10 IU/mL were also tested. B19V was detected in 5/5 PCC samples and 5/5 factor VIII samples but was not found in the intravenous immune globulin and albumin samples. The contamination of B19V in pooled plasma and plasma-derived clotting factor concentrates is serious. Whether B19V nucleic acid testing (NAT) screening of plasma and plasma derivatives is launched in China, blood product manufacturers should spontaneously perform B19V NAT screening in plasma donors and mini-pool plasma. These measures can ensure that samples with high titer B19V DNA are discarded in order to prevent and control this transfusion transmitted virus.
Simple prediction of COVID-19 convalescent plasma units with high levels of neutralization antibodies
Background Hyperimmune convalescent COVID-19 plasma (CCP) containing anti-SARS-CoV-2 neutralizing antibodies (NAbs) was proposed as a therapeutic option for patients early in the new coronavirus disease pandemic. The efficacy of this therapy depends on the quantity of neutralizing antibodies (NAbs) in the CCP units, with titers  ≥  1:160 being recommended. The standard neutralizing tests (NTs) used for determining appropriate CCP donors are technically demanding and expensive and take several days. We explored whether they could be replaced by high-throughput serology tests and a set of available clinical data. Methods Our study included 1302 CCP donors after PCR-confirmed COVID-19 infection. To predict donors with high NAb titers, we built four (4) multiple logistic regression models evaluating the relationships of demographic data, COVID-19 symptoms, results of various serological testing, the period between disease and donation, and COVID-19 vaccination status. Results The analysis of the four models showed that the chemiluminescent microparticle assay (CMIA) for the quantitative determination of IgG Abs to the RBD of the S1 subunit of the SARS-CoV-2 spike protein was enough to predict the CCP units with a high NAb titer. CCP donors with respective results > 850 BAU/ml SARS-CoV-2 IgG had a high probability of attaining sufficient NAb titers. Including additional variables such as donor demographics, clinical symptoms, or time of donation into a particular predictive model did not significantly increase its sensitivity and specificity. Conclusion A simple quantitative serological determination of anti-SARS-CoV-2 antibodies alone is satisfactory for recruiting CCP donors with high titer NAbs.
Using an Extended Theory of Planned Behavior to Predict a Change in the Type of Blood Product Donated
Background Demand for essential plasma-derived products is increasing. Purpose This prospective study aims to identify predictors of voluntary non-remunerated whole blood (WB) donors becoming plasmapheresis donors. Methods Surveys were sent to WB donors who had recently (recent n  = 1,957) and not recently donated (distant n  = 1,012). Theory of Planned Behavior (TPB) constructs (attitude, subjective norm, self-efficacy) were extended with moral norm, anticipatory regret, and donor identity. Intentions and objective plasmapheresis donation for 527 recent and 166 distant participants were assessed. Results Multi-group analysis revealed that the model was a good fit. Moral norm and self-efficacy were positively associated while role identity (suppressed by moral norm) was negatively associated with plasmapheresis intentions. Conclusions The extended TPB was useful in identifying factors that facilitate conversion from WB to plasmapheresis donation. A superordinate donor identity may be synonymous with WB donation and, for donors with a strong moral norm for plasmapheresis, may inhibit conversion.
Peripheral Blood Immune Profiling of Convalescent Plasma Donors Reveals Alterations in Specific Immune Subpopulations Even at 2 Months Post SARS-CoV-2 Infection
Immune profiling of patients with COVID-19 has shown that SARS-CoV-2 causes severe lymphocyte deficiencies (e.g., lymphopenia, decreased numbers, and exhaustion of T cells) and increased levels of pro-inflammatory monocytes. Peripheral blood (PB) samples from convalescent plasma (CP) donors, COVID-19 patients, and control subjects were analyzed by multiparametric flow cytometry, allowing the identification of a wide panel of immune cells, comprising lymphocytes (T, B, natural killer (NK) and NKT cells), monocytes, granulocytes, and their subsets. Compared to active COVID-19 patients, our results revealed that the immune profile of recovered donors was restored for most subpopulations. Nevertheless, even 2 months after recovery, CP donors still had reduced levels of CD4+ T and B cells, as well as granulocytes. CP donors with non-detectable levels of anti-SARS-CoV-2-specific antibodies in their serum were characterized by higher Th9 and Th17 cells, which were possibly expanded at the expense of Th2 humoral immunity. The most noticeable alterations were identified in previously hospitalized CP donors, who presented the lowest levels of CD8+ regulatory T cells, the highest levels of CD56+CD16− NKT cells, and a promotion of a Th17-type phenotype, which might be associated with a prolonged pro-inflammatory response. A longer follow-up of CP donors will eventually reveal the time needed for full recovery of their immune system competence.