BACKGROUND In 2011 and 2013, the National Blood Collection and Utilization Survey (NBCUS) revealed declines in blood collection and transfusion in the United States. The objective of this study was to describe blood services in 2015. STUDY DESIGN AND METHODS The 2015 NBCUS was distributed to all US blood collection centers, all hospitals performing at least 1000 surgeries annually, and a 40% random sample of hospitals performing 100 to 999 surgeries annually. Weighting and imputation were used to generate national estimates for units of blood and components collected, deferred, distributed, transfused, and outdated. RESULTS Response rates for the 2015 NBCUS were 78.4% for blood collection centers and 73.9% for transfusing hospitals. In 2015, 12,591,000 units of red blood cells (RBCs) (95% confidence interval [CI], 11,985,000‐13,197,000 units of RBCs) were collected, and 11,349,000 (95% CI, 10,592,000‐11,747,000) were transfused, representing declines since 2013 of 11.6% and 13.9%, respectively. Total platelet units distributed (2,436,000; 95% CI, 2,230,000‐2,642,000) and transfused (1,983,000; 95% CI, 1,816,000 = 2,151,000) declined by 0.5% and 13.1%, respectively, since 2013. Plasma distributions (3,714,000; 95% CI, 3,306,000‐4,121,000) and transfusions (2,727,000; 95% CI, 2,594,000‐2,859,000) in 2015 declined since 2013. The median price paid per unit in 2015—$211 for leukocyte‐reduced RBCs, $524 for apheresis platelets, and $54 for fresh frozen plasma—was less for all components than in 2013. CONCLUSIONS The 2015 NBCUS findings suggest that continued declines in demand for blood products resulted in fewer units collected and distributed Maintaining a blood inventory sufficient to meet routine and emergent demands will require further monitoring and understanding of these trends.

IMPORTANCE People who have been infected with or vaccinated against SARS-CoV-2 have reduced risk of subsequent infection, but the proportion of people in the US with SARS-CoV-2 antibodies from infection or vaccination is uncertain.OBJECTIVE To estimate trends in SARS-CoV-2 seroprevalence related to infection and vaccination in the US population. DESIGN, SETTING, AND PARTICIPANTSIn a repeated cross-sectional study conducted each month during July 2020 through May 2021, 17 blood collection organizations with blood donations from all 50 US states; Washington, DC; and Puerto Rico were organized into 66 study-specific regions, representing a catchment of 74% of the US population. For each study region, specimens from a median of approximately 2000 blood donors were selected and tested each month; a total of 1 594 363 specimens were initially selected and tested. The final date of blood donation collection was May 31, 2021. EXPOSURE Calendar time.MAIN OUTCOMES AND MEASURES Proportion of persons with detectable SARS-CoV-2 spike and nucleocapsid antibodies. Seroprevalence was weighted for demographic differences between the blood donor sample and general population. Infection-induced seroprevalence was defined as the prevalence of the population with both spike and nucleocapsid antibodies. Combined infection-and vaccination-induced seroprevalence was defined as the prevalence of the population with spike antibodies. The seroprevalence estimates were compared with cumulative COVID-19 case report incidence rates. RESULTS Among 1 443 519 specimens included, 733 052 (50.8%) were from women, 174 842 (12.1%) were from persons aged 16 to 29 years, 292 258 (20.2%) were from persons aged 65 years and older, 36 654 (2.5%) were from non-Hispanic Black persons, and 88 773 (6.1%) were from Hispanic persons. The overall infection-induced SARS-CoV-2 seroprevalence estimate increased from 3.5% (95% CI, 3.2%-3.8%) in July 2020 to 20.2% (95% CI, 19.9%-20.6%) in May 2021; the combined infection-and vaccination-induced seroprevalence estimate in May 2021 was 83.3% (95% CI, 82.9%-83.7%). By May 2021, 2.1 SARS-CoV-2 infections (95% CI, 2.0-2.1) per reported COVID-19 case were estimated to have occurred. CONCLUSIONS AND RELEVANCEBased on a sample of blood donations in the US from July 2020 through May 2021, vaccine-and infection-induced SARS-CoV-2 seroprevalence increased over time and varied by age, race and ethnicity, and geographic region. Despite weighting to adjust for demographic differences, these findings from a national sample of blood donors may not be representative of the entire US population.

INTRODUCTION The National Blood Collection and Utilization Survey (NBCUS) has demonstrated declines in blood collection and transfusion in the United States since 2008, including declines of 11.6% in red blood cell (RBC) collections and 13.9% in RBC transfusions during 2013‐2015. This study described the 2017 NBCUS results. METHODS The 2017 NBCUS was distributed to all US blood collection centers, all hospitals performing at least 1000 surgeries annually, and a 40% random sample of hospitals performing 100 to 999 surgeries annually. Weighting and imputation were used to generate national estimates for units of blood and components collected, deferred, distributed, transfused, and outdated. RESULTS Response rates for the 2017 NBCUS were 88% for blood collection centers and 86% for transfusing hospitals. Compared with 2015, the number of RBC units collected during 2017 (12,211,000; 95% confidence interval [CI], 11,680,000‐12,742,000) declined by 3.0%, and transfused RBC units (10,654,000, 95% CI, 10,314,000‐10,995,000) declined by 6.1%. Distributed platelet (PLT) units (2,560,000; 95% CI, 2,391,000‐2,730,000 units) increased by 5.1%, and transfused PLT units (1,937,000, 95% CI, 1,794,000‐2,079,000) declined by 2.3%. Distributed plasma units (3,209,000; 95% CI, 2,879,000‐3,539,000) declined by 13.6%, and transfused plasma units (2,374,000; 95% CI, 2,262,000‐2,487,000) declined by 12.9%. CONCLUSION The 2017 NBCUS suggests a continued but slowing decline in demand for RBCs. The decline in blood collection and use will likely continue. Despite decreasing demand and increasing manufacturing costs of blood products, the US blood industry has met the regular and emergent needs of the country.

Background In 2010, health care facilities in the United States began voluntary enrollment in the National Healthcare Safety Network (NHSN) Hemovigilance Module. Participants report transfusion practices; red blood cell, platelet (PLT), plasma, and cryoprecipitate units transfused; and transfusion‐related adverse reactions and process errors to the Centers for Disease Control and Prevention through a secure, Internet‐accessible surveillance application available to transfusing facilities. Study Design and Methods Facilities submitting at least 1 month of transfused components data and adverse reactions from January 1, 2010, to December 31, 2012, were included in this analysis. Adverse reaction rates for transfused components, stratified by component type and collection and modification methods, were calculated. Results In 2010 to 2012, a total of 77 facilities reported 5136 adverse reactions among 2,144,723 components transfused (239.5/100,000). Allergic (46.8%) and febrile nonhemolytic (36.1%) reactions were most frequent; 7.2% of all reactions were severe or life‐threatening and 0.1% were fatal. PLT transfusions (421.7/100,000) had the highest adverse reaction rate. Conclusion Adverse transfusion reaction rates from the NHSN Hemovigilance Module in the United States are comparable to early hemovigilance reporting from other countries. Although severe reactions are infrequent, the numbers of transfusion reactions in US hospitals suggest that interventions to prevent these reactions are important for patient safety. Further investigation is needed to understand the apparent increased risk of reactions from apheresis‐derived blood components. Comprehensive evaluation, including data validation, is important to continued refinement of the module.