Predicting SARS-CoV-2 variant spread in a completely seropositive population using semi-quantitative antibody measurements in blood donors

SARS-CoV-2 serologic surveys estimate the proportion of the population with antibodies against historical variants, which nears 100% in many settings. New approaches are required to fully exploit serosurvey data. Using a SARS-CoV-2 anti-Spike (S) protein chemiluminescent microparticle assay, we attained a semi-quantitative measurement of population IgG titers in serial cross-sectional monthly samples of blood donations across seven Brazilian state capitals (March 2021–November 2021). Using an ecological analysis, we assessed the contributions of prior attack rate and vaccination to antibody titer. We compared anti-S titer across the seven cities during the growth phase of the Delta variant and used this to predict the resulting age-standardized incidence of severe COVID-19 cases. We tested ~780 samples per month, per location. Seroprevalence rose to >95% across all seven capitals by November 2021. Driven by vaccination, mean antibody titer increased 16-fold over the study, with the greatest increases occurring in cities with the highest prior attack rates. Mean anti-S IgG was strongly correlated (adjusted R2 = 0.89) with the number of severe cases caused by Delta. Semi-quantitative anti-S antibody titers are informative about prior exposure and vaccination coverage and may also indicate the potential impact of future SARS-CoV-2 variants

Infusion of Hematopoietic Stem Cells: Types, Characteristics, Adverse and Transfusion Reactions and the Implications for Nursing Infusión de células madre hematopoyéticas: tipos, características, reacciones adversas y de transfusión y sus implicaciones para la enfermería Infusão de células-tronco hematopoéticas: tipos, características, reações adversas e transfusionais e implicações para a enfermagem

Hematopoietic stem cell infusion is an important procedure in Hematopoietic Stem Cell Transplantation (HSCT). This study identifies transfusion and other adverse reactions that can occur during infusion and the nursing care related to the procedure. This epidemiologic study used transplantations performed between 2006 and 2008. A total of 166 transplantations were performed: 114 were autologous, 47 allogeneic and five haploidentical. Three transfusion reactions and 96 adverse reactions were observed. Adverse reactions were related to the presence of cryoprotectant, though the infusion rate and quantity of infused cryoprotectant were not related to the occurrence of reactions. The products were fresh and infused within the recommended time when transfusion reactions occurred. In regard to cell source, lower engraftment time was found in peripheral blood. Nursing documentation is relevant for patients&#39; safety as well to planning an infusion in order to minimize the occurrence of reactions.<br>La infusión de las células madre hematopoyéticas es un importante procedimiento en el trasplante de células madre hematopoyéticas. Este estudio se propuso identificar las reacciones adversas y de transfusión que pueden ocurrir durante la infusión y los cuidados de enfermería inherentes al procedimiento. Se trata de un estudio epidemiológico en trasplantes ocurridos en los años de 2006 a 2008. En ese período ocurrieron 166 trasplantes, siendo 114 autólogos, 47 alogénicos y 5 haploidénticos. Se observaron tres reacciones de transfusión y 96 reacciones adversas. Las reacciones adversas están ligadas a presencia del crioprotector. Sin embargo, la velocidad de infusión y la cantidad del crioprotector infundido, no tuvieron relación con la ocurrencia de las reacciones. En las reacciones de transfusión, los productos eran frescos e infundidos con la velocidad preconizada. En cuanto a las fuentes de células, hubo menor tiempo de injerto en la sangre periférica. La documentación de enfermería es relevante tanto para la seguridad del paciente como para la planificación de la infusión, a fin de minimizar la ocurrencia de las reacciones.<br>A infusão de células-tronco hematopoéticas é importante procedimento no transplante de células-tronco hematopoéticas. Este estudo se propôs a identificar as reações adversas e transfusionais que podem ocorrer durante a infusão e os cuidados de enfermagem inerentes ao procedimento. Trata-se de estudo epidemiológico em transplantes, ocorridos entre os anos 2006 e 2008. Ocorreram 166 transplantes, sendo 114 autólogos, 47 alogênicos e 5 haploidênticos. Observaram-se três reações transfusionais e 96 reações adversas. As reações adversas estão ligadas à presença do crioprotetor. No entanto, velocidade de infusão e quantidade do crioprotetor infundido não tiveram relação com a ocorrência das reações. Nas reações transfusionais, os produtos eram frescos e infundidos na velocidade preconizada. Quanto às fontes de células, houve menor tempo de enxertia no sangue periférico. A documentação de enfermagem é relevante tanto para a segurança do paciente como para o planejamento da infusão, a fim de minimizar a ocorrência das reações

Criopreservação de medula óssea e células pluripotentes periféricas utilizando um congelador programável: experiência em 86 congelamentos Cryopreservation of bone marrow and peripheral blood stem cells using a controlled rate freezing system. Experience on 86 procedures

A infusão de células hematopoéticas totipotentes criopreservadas permite a recuperação da hematopoese após quimioterapia mieloablativa. OBJETIVO. A formação de cristais de gelo durante o processo de congelamento é o fator principal que causa ruptura das estruturas celulares. A criopreservação dessas células a uma taxa constante preveniria os danos causados pelo congelamento brusco. MÉTODOS. Vinte e três pacientes com mediana de 25 anos (variação 3-57) tiveram a medula óssea e/ou células-tronco periféricas (CTP) coletadas no período de março de 1993 a outubro de 1994, totalizando 86 congelamentos. Os pacientes apresentavam as seguintes neoplasias: linfoma não-Hodgkin (n=5), leucemia mielóide aguda (n=8), leucemia linfóide aguda (n=6), doença de Hodgkin (n=3) e mieloma múltiplo (n=1). O congelamento foi controlado por um computador, acoplado ao sistema, às seguintes temperaturas: -1°C/min até -45°C e depois a -10°C/min até -80°C. Após o congelamento, as células foram mantidas em freezer a -110°C até o momento da infusão. Para obtenção das CTP, empregou-se o fator de crescimento estimulante de granulócitos (G-CSF). RESULTADOS. Uma mediana de 3,16 x 10(8) céls./kg (variação 0,86-24,22) de CTP e 2,03 x 10(8) céls./kg (variação 0,19-12,21) de medula óssea foi congelada. A mediana para atingir granulócitos maior ou igual a 500/µL e plaquetas maior que 20.000/µL foi de 12 dias (variação 8-40) e 31 dias (variação 8-80), respectivamente. Todos os pacientes tiveram recuperação hematopoética após a infusão das células criopreservadas. CONCLUSÃO. A criopreservação em congelador programável permite o armazenamento de células hematopoéticas e, potencialmente, pode causar menor dano celular.<br>The cryopreservation of hematopoietic stem cells can be used for rescuing the hematopoiesis after high dose chemotherapy. PURPOSE. The ice cristal formation during the freezing procedure is the key point that can be harmful to the cells. The cryopreservation of hematopoietic stem cells in a controlled-rate freezer could decrease the cell damage. METHODS. Twenty-three patients with a median age of 26 years (range 03-57) had bone marrow and/or peripheral blood stem cells harvested from March 1993 through October 1994, ending up to 86 freezing procedures. The patient's diagnoses are as follows: Non-Hodgkin's Lymphoma (n=5); Acute Myelogenous Leukemia (n=8); Acute Lymphocytic Leukemia (n=6); Hodgkin's disease (n=3); Multiple Myeloma (n=1). The cells were frozen away in a controlled-rate freezer chamber at the folowing rate: -1°C/min from room temperature to -45°C and then, at -10°C/min down to -80°C. After freezing, the cells were kept into mechanical freezers until the marrow infusion. To mobilize PBSC (peripheral blood stem cells), G-CSF (granulocyte colony stimulating factor) was given. RESULTS. A median of 3.16x10(8) cells/kg (range 0.86-24.22) of PBSC and 2.03x10(8) cells/kg (0.19-12.21) of bone marrow cells were frozen. The median time to reach granulocytes greater than 500/µL and platelets greater than 20,000/µL was 12 days (range 8-40) and 31 days (range 8-80), respectively. All patients had marrow engraftment after infusion of hematopoietic stem cells. CONCLUSION. The cryopreservation procedure using a controlled-rate freezer can store hematopoietic stem cells and potentially, cause less damage to the cells

HCV genotype distribution according donor demographics, risk factors, and HCV viral load.

*<p>Pearson’s chi-squared test.</p>**<p>Tukey’s t test.</p

Frequency of blood donors with mutations conferring resistance to protease inhibitors according to demographics, risk factors, subtypes, and HCV viral load.

*<p>Pearson;s chi-squared test.</p>**<p>Tukey’s t test.</p

Amino acid substitutions and frequency of blood donors with mutations conferring resistance to protease inhibitors.

<p>Amino acid substitutions and frequency of blood donors with mutations conferring resistance to protease inhibitors.</p

Flowchart summarizing the routine screening and confirmatory testing for HCV and the results of the genotyping and protease inhibitor-resistance mutation analyses.

<p>Notes: EIA - Enzyme immunoassay (EIA); IB - Immunoblot assay.</p

Higher risk of death from COVID-19 in low-income and non-White populations of São Paulo, Brazil

Introduction Little evidence exists on the differential health effects of COVID-19 on disadvantaged population groups. Here we characterise the differential risk of hospitalisation and death in São Paulo state, Brazil, and show how vulnerability to COVID-19 is shaped by socioeconomic inequalities. Methods We conducted a cross-sectional study using hospitalised severe acute respiratory infections notified from March to August 2020 in the Sistema de Monitoramento Inteligente de São Paulo database. We examined the risk of hospitalisation and death by race and socioeconomic status using multiple data sets for individual-level and spatiotemporal analyses. We explained these inequalities according to differences in daily mobility from mobile phone data, teleworking behaviour and comorbidities. Results Throughout the study period, patients living in the 40% poorest areas were more likely to die when compared with patients living in the 5% wealthiest areas (OR: 1.60, 95% CI 1.48 to 1.74) and were more likely to be hospitalised between April and July 2020 (OR: 1.08, 95% CI 1.04 to 1.12). Black and Pardo individuals were more likely to be hospitalised when compared with White individuals (OR: 1.41, 95% CI 1.37 to 1.46; OR: 1.26, 95% CI 1.23 to 1.28, respectively), and were more likely to die (OR: 1.13, 95% CI 1.07 to 1.19; 1.07, 95% CI 1.04 to 1.10, respectively) between April and July 2020. Once hospitalised, patients treated in public hospitals were more likely to die than patients in private hospitals (OR: 1.40%, 95% CI 1.34% to 1.46%). Black individuals and those with low education attainment were more likely to have one or more comorbidities, respectively (OR: 1.29, 95% CI 1.19 to 1.39; 1.36, 95% CI 1.27 to 1.45). Conclusions Low-income and Black and Pardo communities are more likely to die with COVID-19. This is associated with differential access to quality healthcare, ability to self-isolate and the higher prevalence of comorbidities