Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread rapidly in Manaus, the capital of Amazonas state in northern Brazil. The attack rate there is an estimate of the final size of the largely unmitigated epidemic that occurred in Manaus. We use a convenience sample of blood donors to show that by June 2020, 1 month after the epidemic peak in Manaus, 44% of the population had detectable immunoglobulin G (IgG) antibodies. Correcting for cases without a detectable antibody response and for antibody waning, we estimate a 66% attack rate in June, rising to 76% in October. This is higher than in São Paulo, in southeastern Brazil, where the estimated attack rate in October was 29%. These results confirm that when poorly controlled, COVID-19 can infect a large proportion of the population, causing high mortality.

Background In Brazil nationally representative donor data are limited on HIV prevalence, incidence and residual transfusion risk. The objective of this study was to analyze HIV data obtained over 24 months by the REDS-II program in Brazil. Methods Donations reactive to 3rd and 4th generation immunoassays (IAs) were further confirmed by a less-sensitive (LS) IA algorithm and Western blot (WB). Incidence was calculated for first-time (FT) donors using the LS-EIA results and for repeat donors with a model developed to include all donors with a previous negative donation. Residual risk was projected by multiplying composite FT/repeat donor incidence rates by HIV marker-negative infectious window periods. Results HIV prevalence among FT donors was 92.2/105 donations. FT, repeat donor and composite incidence were 38.5 (95%CI: 25.6–51.4), 22.5 (95%CI: 17.6–28.0) and 27.5 (95%CI: 22.0–33.0) per 100,000 person-years, respectively. Male and community donors had higher prevalence and incidence rates than female and replacement donors. Estimated residual risk of HIV transfusion-transmission was 11.3 per 106 donations (95%CI: 8.4–14.2), which could be reduced to 4.2 per 106 donations (95%CI: 3.2–5.2) by use of individual donation nucleic acid testing (NAT). Conclusion Incidence and residual transfusion risk of HIV infection are relatively high in Brazil. Implementation of NAT testing will not be sufficient to decrease transmission rates to levels seen in the US or Europe, therefore other measures focused on decreasing donations by at-risk individuals are also necessary.

HIV incidence and residual transfusion risk estimates are approximately 10 times higher in Brazil FT donors compared to US and European FT donors. Community FT donors had higher HIV prevalence than replacement FT donors. The yield of p24 antigen or RNA screening will be low in Brazilian donors, but substantially higher than in US donors.

No single test for Chagas' disease is sufficiently sensitive to prevent transfusion transmission of the disease in the urban centers of Brazil.

Recruiting safe, volunteer blood donors requires understanding motivations for donating and knowledge and attitudes about HIV. We surveyed 1,600 persons presenting for blood donation at a large blood bank in São Paulo, Brazil using a self-administered, structured questionnaire, and classified motivations into three domains as well as categorizing persons by HIV test-seeking behavior. Motivations, in descending order, and their significant associations were: "altruism": female gender, volunteer donor and repeat donor status; "direct appeal": female gender, repeat donor status and age 21-50 years; "self-interest": male gender, age under 20 years, first-time donor status and lower education. HIV test-seekers were more likely to give incorrect answers regarding HIV risk behavior and blood donation and the ability of antibody testing to detect recent HIV infections. Altruism is the main motivator for blood donation in Brazil; other motivators were associated with specific demographic subgroups. HIV test-seeking might be reduced by educational interventions.

This case brings additional evidence that dengue is indeed transmissible by blood transfusion and clinical manifestations, although rare, do occur.

IntroductionLittle 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.MethodsWe 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.ResultsThroughout 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).ConclusionsLow-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.

Human T-lymphotropic virus type 1/2 (HTLV-1/2) infection is endemic in Brazil but representative donor prevalence and incidence data are lacking. All blood donations (2007)(2008)(2009)) from three blood centers in Brazil were studied. Samples reactive on one HTLV screening test (EIA) were retested with a different EIA; dual EIA reactivity correlated strongly with a confirmatory Western blot. Prevalence, incidence, and residual transfusion risk were calculated. Among 281,760 first-time donors, 363 were positive for HTLV on both EIAs (135 per 10 5 , 95% CI 122-150). Prevalence differed considerably by region, from 83 to 222 per 10 5 . Overall incidence rate was 3.6/10 5 person-years and residual transfusion risk was 5.0/10 6 per blood unit transfused. The logistic regression model showed significant associations with: age [adjusted odds ratio (aOR) = 5.23 for age 50 + vs. < 20], female sex (aOR = 1.97), black (aOR = 2.70 vs. white), and mixed skin colors (aOR = 1.78 vs. white), and inversely with education (aOR = 0.49, college vs. less than high school). HTLV testing with a dual-EIA strategy is feasible and can be useful in areas with low resources. Incidence and residual risk of HTLV-1 transmission by transfusion were relatively high and could be reduced by improving donor recruitment and selection in high prevalence areas. Blood center data may contribute to surveillance for HTLV infection.