Patient and immunological factors associated with delayed clearance of mucosal SARS-CoV-2 RNA and symptom persistence.

Serial blood and mucosal samples were characterized for 102 participants enrolled a median of 7.0 days post-COVID-19 diagnosis. Mucosal RNA was detectable a median 31.5 (95% CI 20.5 - 63.5) days, with persistence ≥1 month associated with obesity (BMI ≥30, OR 3.9, 95% CI 1.2 - 13.8) but not age, sex, or chronic conditions. Fifteen participants had likely reinfection; lower serum anti-S IgG levels were associated with reinfection risk. Nearly half of participants (47%) reported symptoms lasting ≥2-3 months; persistence ≥3 months was associated with BMI ≥30 (OR = 4.2 95% CI 1.1 - 12.8) and peak anti-S and anti-NC antibody levels.

Transmission of yellow fever vaccine virus through blood transfusion and organ transplantation in the USA in 2021: report of an investigation.

BACKGROUND: In 2021, four patients who had received solid organ transplants in the USA developed encephalitis beginning 2-6 weeks after transplantation from a common organ donor. We describe an investigation into the cause of encephalitis in these patients. METHODS: From Nov 7, 2021, to Feb 24, 2022, we conducted a public health investigation involving 15 agencies and medical centres in the USA. We tested various specimens (blood, cerebrospinal fluid, intraocular fluid, serum, and tissues) from the organ donor and recipients by serology, RT-PCR, immunohistochemistry, metagenomic next-generation sequencing, and host gene expression, and conducted a traceback of blood transfusions received by the organ donor. FINDINGS: We identified one read from yellow fever virus in cerebrospinal fluid from the recipient of a kidney using metagenomic next-generation sequencing. Recent infection with yellow fever virus was confirmed in all four organ recipients by identification of yellow fever virus RNA consistent with the 17D vaccine strain in brain tissue from one recipient and seroconversion after transplantation in three recipients. Two patients recovered and two patients had no neurological recovery and died. 3 days before organ procurement, the organ donor received a blood transfusion from a donor who had received a yellow fever vaccine 6 days before blood donation. INTERPRETATION: This investigation substantiates the use of metagenomic next-generation sequencing for the broad-based detection of rare or unexpected pathogens. Health-care workers providing vaccinations should inform patients of the need to defer blood donation for at least 2 weeks after receiving a yellow fever vaccine. Despite mitigation strategies and safety interventions, a low risk of transfusion-transmitted infections remains. FUNDING: US Centers for Disease Control and Prevention (CDC), the Biomedical Advanced Research and Development Authority, and the CDC Epidemiology and Laboratory Capacity Cooperative Agreement for Infectious Diseases.

Prevalence of SARS-CoV-2 Viremia in Presymptomatic Blood Donors in the Delta and Omicron Variant Eras.

Presymptomatic plasma samples from 1596 donors reporting coronavirus disease 2019 infection or symptoms after blood donation were tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and anti-S and anti-N antibodies. Prior infection and vaccination both protected from developing SARS-CoV-2 RNAemia and from symptomatic infection. RNAemia rates did not differ in the Delta and Omicron variant eras.

Blood donation motivators and barriers reported by young, first-time whole blood donors: Examining the association of reported motivators and barriers with subsequent donation behavior and potential sex, race, and ethnic group differences.

BACKGROUND: A greater understanding of young, first-time donor motivators and barriers is needed to address the ongoing challenge of retaining these essential donors. STUDY DESIGN AND METHODS: Structured interviews conducted with 508 young, first-time whole blood donors [66.1% female; Mean Age = 19.4 (SD = 2.5) years] were coded to identify reported motivators and barriers. Reported motivators and barriers were then examined for their association with attempted donation behavior over a 14-month follow-up, and for potential sex, race, and ethnic group differences in the frequency of endorsement. RESULTS: Prosocial motivation (e.g., altruism) was the most commonly reported motivator and fear (e.g., fainting, needles) was the most commonly reported barrier. Donation behavior was unrelated to reported motivators, but was significantly related to four reported barriers including fear of fainting/dizziness, fear of needles/pain, having personal commitments that conflict with donating, and perceiving oneself as unsuited to donate for health reasons. Sex, racial, and ethnic differences were noted with respect to the percentages of donors reporting several donation-related motivators and barriers. CONCLUSION: The present findings identify donation-related barriers that could be important targets to address in the effort to encourage new young donors and to retain these new donors for the long term. Importantly, these data also highlight the importance of considering individual differences in donor motivation as a function of sex, race, and ethnicity.

A randomized trial of blood donor iron repletion on red cell quality for transfusion and donor cognition and well-being.

Although altruistic regular blood donors are vital for the blood supply, many become iron deficient from donation-induced iron loss. The effects of blood donation-induced iron deficiency on red cell transfusion quality or donor cognition are unknown. In this double-blind, randomized trial, adult iron-deficient blood donors (n = 79; ferritin < 15 µg/L and zinc protoporphyrin >60 µMol/mol heme) who met donation qualifications were enrolled. A first standard blood donation was followed by the gold-standard measure for red cell storage quality: a 51-chromium posttransfusion red cell recovery study. Donors were then randomized to intravenous iron repletion (1 g low-molecular-weight iron dextran) or placebo. A second donation ∼5 months later was followed by another recovery study. Primary outcome was the within-subject change in posttransfusion recovery. The primary outcome measure of an ancillary study reported here was the National Institutes of Health Toolbox-derived uncorrected standard Cognition Fluid Composite Score. Overall, 983 donors were screened; 110 were iron-deficient, and of these, 39 were randomized to iron repletion and 40 to placebo. Red cell storage quality was unchanged by iron repletion: mean change in posttransfusion recovery was 1.6% (95% confidence interval -0.5 to 3.8) and -0.4% (-2.0 to 1.2) with and without iron, respectively. Iron repletion did not affect any cognition or well-being measures. These data provide evidence that current criteria for blood donation preserve red cell transfusion quality for the recipient and protect adult donors from measurable effects of blood donation-induced iron deficiency on cognition. This trial was registered at www.clinicaltrials.gov as NCT02889133 and NCT02990559.

Frequent detection but lack of infectivity of SARS-CoV-2 RNA in presymptomatic, infected blood donor plasma.

Respiratory viruses such as influenza do not typically cause viremia; however, SARS-CoV-2 has been detected in the blood of COVID-19 patients with mild and severe symptoms. Detection of SARS-CoV-2 in blood raises questions about its role in pathogenesis as well as transfusion safety concerns. Blood donor reports of symptoms or a diagnosis of COVID-19 after donation (post-donation information, PDI) preceded or coincided with increased general population COVID-19 mortality. Plasma samples from 2,250 blood donors who reported possible COVID-19-related PDI were tested for the presence of SARS-CoV-2 RNA. Detection of RNAemia peaked at 9%-15% of PDI donors in late 2020 to early 2021 and fell to approximately 4% after implementation of widespread vaccination in the population. RNAemic donors were 1.2- to 1.4-fold more likely to report cough or shortness of breath and 1.8-fold more likely to report change in taste or smell compared with infected donors without detectable RNAemia. No infectious virus was detected in plasma from RNAemic donors; inoculation of permissive cell lines produced less than 0.7-7 plaque-forming units (PFU)/mL and in susceptible mice less than 100 PFU/mL in RNA-positive plasma based on limits of detection in these models. These findings suggest that blood transfusions are highly unlikely to transmit SARS-CoV-2 infection.

Promoting awareness of donation-related iron depletion among high risk blood donors.

BACKGROUND: The potential for iron deficiency is a known blood donor health concern and suggests the need to inform donors about the potential risks of low iron levels as well as strategies to address these risks. STUDY DESIGN AND METHODS: Frequent (n = 904) and young (n = 629) donors were randomly assigned within risk group to either a control (n = 548) or an intervention (n = 985) group. The control group answered questions at baseline and 6-month follow-up regarding their awareness of the risk of donation-related iron depletion and whether they were taking actions to address their iron status. The intervention group answered the same questions at baseline and follow-up, but after completing the baseline survey, they received information regarding their risk of iron depletion and behaviors they could adopt to mitigate this risk. Intervention group participants were also offered the opportunity to develop an action plan to help them supplement their iron intake. RESULTS: The intervention enhanced overall awareness of donation-related iron loss (OR = 1.5, 95% CI 1.171-1.864, p = .001), with no negative impact on retention. Reported iron health behaviors (iron supplementation, speaking with a doctor) showed significant increases when action planning was paired with the educational information. CONCLUSION: These findings suggest that it is possible to increase awareness of donation-related risk for iron depletion without negatively influencing retention, and combining education with encouragement to develop an action plan may increase the likelihood of both retention and behavioral changes to promote healthy iron levels.

Fear is associated with attrition of first-time whole blood donors: A longitudinal examination of donor confidence and attitude as potential mediators.

BACKGROUND: Elevated fear and anxiety regarding donation-related stimuli (e.g., needles, pain, blood, fainting) has been associated with reduced blood donor recruitment and retention. The present longitudinal study tests the notion that this inverse relationship may be accounted for by lower donation confidence and more negative donation attitudes among fearful first-time donors. STUDY DESIGN AND METHODS: In a sample of 1479 first-time whole blood donors [67.9% female; mean age = 19.3 (standard deviation (SD) = 2.5) years], path analyses were conducted to examine relationships among donor ratings of fear of blood draw and donation anxiety obtained approximately 1 week after donation, donation confidence and attitudes assessed approximately 6 weeks later, and donation attempts over the 14 months following the original donation. RESULTS: Path analyses indicated that both fear of blood draws and donation anxiety were associated with fewer attempted donations, and that these effects were indirectly mediated by a combination of lower donor confidence and more negative donation attitudes. CONCLUSION: Because retention of new blood donors is essential to maintain a healthy blood supply, the results of the present study suggest that first-time donors should be assessed for fear and anxiety so that appropriate strategies can be provided to address their concerns, bolster their confidence and attitudes, and ultimately promote their long-term retention.

Results from the blood donor competence, autonomy, and relatedness enhancement (blood donor CARE) randomized trial.

BACKGROUND: This study aimed to promote competence, autonomy, and relatedness among first-time whole blood donors to enhance intrinsic motivation and increase retention. STUDY DESIGN AND METHODS: Using a full factorial design, first-time donors (N = 2002) were randomly assigned to a no-treatment control condition or to one of seven intervention conditions designed to promote donation competence, autonomy, relatedness, a combination of two (e.g., competence and autonomy), or all three constructs. Participants completed donor motivation measures before the intervention and 6 weeks later, and subsequent donation attempts were assessed for 1 year. RESULTS: There was no significant group difference in the frequency of donation attempts or in the number of days to return. Significant effects of group were observed for 10 of the 12 motivation measures, although follow-up analyses revealed significant differences from the control group were restricted to interventions that included an autonomy component. Path analyses confirmed direct associations between interventions involving autonomy and donor motivation, and indirect mediation of donation attempts via stronger donation intentions and lower donation anxiety. CONCLUSION: Among young, first-time, whole blood donors, brief interventions that include support for donor autonomy were associated with direct effects on donor motivation and indirect, but small, effects on subsequent donation behavior.

Characteristics of coronavirus disease 19 convalescent plasma donors and donations in the New York metropolitan area.

BACKGROUND: Convalescent plasma (CP) is an important initial treatment in pandemics and the New York (NY) metropolitan area is likely to remain a hotspot for collection and distribution of such units. This study reports characteristics of coronavirus disease 19 CP (CCP) donors and their donations to the New York Blood Center (NYBC). STUDY DESIGN AND METHODS: All CCP data from our first day of collection on March 26th through July 7th, 2020 are included in this retrospective analysis. Donor and donation data were extracted from NYBC electronic databases. SARS-CoV-2 antibody testing was initially performed by the NY State Department of Health, and later by NYBC using Ortho and Abbott platforms. RESULTS: CCP donor age and ABO distributions were consistent with reported lower COVID-19 susceptibility in O blood types. CCP versus whole blood donors had similar on-site deferrals, but higher post-donation deferral rates. CCP versus routine plasmapheresis donations had higher vasovagal reactions but similar product rejection rates. Changes in antibody (Ab) test platforms resulted in significant changes in the percent of donors regarded as antibody positive. Donor correlates with higher anti-spike total Ig S/CO ratios were Hispanic ethnicity, overweight body mass index, and longer symptom duration; and with higher anti-nucleocapsid IgG S/CO ratios were male gender, older age, Hispanic ethnicity, and fewer days between symptom onset and first donation. DISCUSSION: We identify donor characteristics not previously reported to correlate with Ab titer. Our analysis should assist with donor outreach strategies, blood center operating logistics, and recruitment of high titer donors.

Prevalence of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus in United States blood donations, 2015 to 2019: The Transfusion-Transmissible Infections Monitoring System (TTIMS).

BACKGROUND: The Transfusion-Transmissible Infections Monitoring System (TTIMS) combines data from four US blood collection organizations including approximately 60% of all donations to monitor demographic and temporal trends in infectious disease markers and policy impacts. STUDY DESIGN AND METHODS: Human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) consensus-positive definitions combined serology and nucleic acid testing results. These along with donor and donation characteristics were assembled into a single data set. Overall donation prevalence and demographic subsets were compared pre- and post-implementation of the 2015 change in men who have sex with men (MSM) deferral policy, among other prevalence comparisons. RESULTS: From October 2015 to September 2019, there were 712 HIV-, 1735 HBV-, and 5217 HCV-positive samples identified from approximately 27.5 million donations (>9.4 million donors). Prevalences per 100 000 donations were 2.6 (HIV), 6.3 (HBV), and 19.0 (HCV), and the highest for all three agents were in donations from first-time male donors. Two slight but significant increases in HIV prevalence were observed, both for comparisons of Year 1 (pre-MSM policy change) versus Year 4 (post-MSM policy change) for first-time males and first-time females; in contrast, similar comparisons demonstrated decreases in HCV prevalence (all donors and general trends for males and females). Except for HIV, prevalence increased with age; for all agents, prevalence was markedly higher in the south. CONCLUSIONS: No major trends were observed over 4 years covering the MSM policy change from indefinite to a 12-month deferral, but ongoing monitoring is warranted. Demographic trends are consistent with those observed in other donor studies and community trends.

Examination of the relationship between iron status and cognitive function among healthy young women with and without a recent history of blood donation.

BACKGROUND: With growing awareness of the prevalence of nonanemic iron deficiency among blood donors, there is a need to explore the extent of potential negative consequences. This study examined the relationship between various measures of iron status, blood donation history, and neuropsychological and psychosocial functioning in healthy young women. STUDY DESIGN AND METHODS: Using a cross-sectional design, 160 female undergraduates completed neuropsychology tests and measures of sleep, fatigue, quality of life, and depression before providing a blood sample. Correlational analyses examined the relationship between iron status (ferritin, iron, hemoglobin, and zinc protoporphyrin) and cognitive and psychosocial functioning. Performance on these measures was also examined as a function of recent blood donation history (zero, one, more than one donation in the past year). RESULTS: Iron status (low ferritin, iron, or hemoglobin or high zinc protoporphyrin) was not associated with poorer performance on the cognitive tasks. Further, participants who reported donating once in the previous year performed better, rather than worse, than those with no recent donation history on several measures of executive function, even when controlling for ferritin levels. Although there was some evidence of greater fatigue among those who had donated more than once in the past year, this effect was not accounted for by ferritin levels. CONCLUSION: The present findings are consistent with prior evidence that nonanemic iron deficiency is not associated with cognitive impairment or psychosocial dysfunction in healthy young females. Because these results are based on cross-sectional evidence, further study using longitudinal research is needed to confirm these findings.

Transcription-mediated amplification blood donation screening for Babesia.

BACKGROUND: Transfusion-transmitted Babesia microti is well recognized in the Northeast and upper Midwestern United States. Blood donation screening in Babesia-endemic states has occurred under investigational protocols prior to US Food and Drug Administration-licensed test availability. Here, we provide a prospective screening summary of nucleic acid testing (NAT) as part of a multicenter Babesia pivotal trial followed by extended investigational use. METHODS: From June 2017 to February 2018, 176,928 donation samples were tested with Procleix Babesia Assay (Grifols Diagnostic Solutions), a blood screening NAT for Babesia species ribosomal RNA detection using whole blood samples. During the pivotal trial, donations were collected in 11 endemic states plus Washington, DC, and Florida (nonendemic). Whole blood lysate samples were either tested in pools of 16 or individually. Reactive samples were confirmed by Babesia microti antibody and polymerase chain reaction (PCR) testing. If unconfirmed, further testing used a second PCR assay capable of detecting multiple Babesia species. Follow-up samples were also tested. Extended investigational testing followed pivotal trial completion. RESULTS: The pivotal trial identified 61 confirmed positives (176,608 donations): 35 (57%) PCR positive, 59 (97%) antibody positive, and two (3%) NAT positive/antibody negative, for a total yield of one positive per 2895 donations, including one Florida resident; others were from seven endemic states. During extended investigational testing of 496,270 donations in endemic states through January 2019, 211 (1:2351) repeat reactive donations were identified. CONCLUSIONS: Babesia was detected in donors from multiple US states, including one previously not associated with positive blood donors. This study supports the use of the Procleix Babesia Assay using individual testing or pools of up to 16.

An automated motivational interview promotes donation intention and self-efficacy among experienced whole blood donors.

BACKGROUND: Interventions intended to motivate donors to return can be costly and time consuming. The current study examined the effect of a Web-based automated interview, informed by motivational interviewing and self-determination theory, on donor intention, motivation, and behavior in a sample of highly experienced donors. STUDY DESIGN AND METHODS: Approximately 1 week after donating, 1177 highly experienced whole blood donors (mean prior donations, 35.5; mean age, 46.9 years; 66.3% female) participated in a study in which they were randomly assigned to either a donor motivational interview (n = 544) or knowledge interview (n = 633). Measures of donor motivation and psychological need support were obtained before the interviews, and again at postinterview assessments conducted approximately 2 days later and 7 weeks later. Blood center records were used to assess repeat donation attempts for 1 year after the interviews. RESULTS: Relative to the knowledge interview, participants in the motivational interview had larger increases in donation intention and self-efficacy from preinterview to the first follow-up. Among women only, the motivational interview was associated with greater competence and relatedness increases at both follow-up assessments. CONCLUSION: An automated motivational interview appears to be a feasible way to promote donation intention and self-efficacy. Although the observed effects were small among highly experienced donors, we are currently assessing the potential effect of this intervention among less experienced donors.

Ten years of TRALI mitigation: measuring our progress.

BACKGROUND: Transfusion-related acute lung injury (TRALI) is a leading cause of transfusion-associated mortality for which multiple mitigation strategies have been implemented over the past decade. However, product-specific TRALI rates have not been reported longitudinally and may help refine additional mitigation strategies. STUDY DESIGN AND METHODS: This retrospective multicenter study included analysis of TRALI rates from 2007 through 2017. Numerators included definite or probable TRALI reports from five blood centers serving nine states in the United States. Denominators were components distributed from participating centers. Rates were calculated as per 100,000 components distributed (p < 0.05 significant). RESULTS: One hundred four TRALI cases were reported from 10,012,707 components distributed (TRALI rate of 1.04 per 100,000 components). The TRALI rate was 2.25 for female versus 1.08 for male donated components (p < .001). The TRALI rate declined from 2.88 in 2007 to 0.60 in 2017. From 2007 to 2013, there was a significantly higher TRALI rate associated with female versus male plasma (33.85 vs. 1.59; p < 0.001) and RBCs (1.97 vs. 1.15; p = 0.03). From 2014 through 2017, after implementation of mitigation strategies, a significantly higher TRALI rate only from female-donated plateletpheresis continued to be observed (2.98 vs. 0.75; p = 0.04). CONCLUSION: Although the TRALI rates have substantially decreased secondary to multiple strategies over the past decade, a residual risk remains, particularly with female-donated plateletpheresis products. Additional tools that may further mitigate TRALI incidence include the use of buffy coat pooled platelets suspended in male donor plasma or platelet additive solution due to the lower amounts of residual plasma.

Transfusion-Transmitted Zika Virus Infection in Pregnant Mice Leads to Broad Tissue Tropism With Severe Placental Damage and Fetal Demise.

Zika virus (ZIKV) infection during pregnancy can cause significant problems, particularly congenital Zika syndrome. Nevertheless, the potential deleterious consequences and associated mechanisms of transfusion-transmitted ZIKV infection on pregnant individuals and their fetuses and babies have not been investigated. Here we examined transmissibility of ZIKV through blood transfusion in ZIKV-susceptible pregnant A129 mice. Our data showed that transfused-transmitted ZIKV at the early infection stage led to significant viremia and broad tissue tropism in the pregnant recipient mice, which were not seen in those transfused with ZIKV-positive (ZIKV+) plasma at later infection stages. Importantly, pregnant mice transfused with early-stage, but not later stages, ZIKV+ plasma also exhibited severe placental infection with vascular damage and apoptosis, fetal infection and fetal damage, accompanied by fetal and pup death. Overall, this study suggests that transfusion-related transmission of ZIKV during initial stage of infection, which harbors high plasma viral titers, can cause serious adverse complications in the pregnant recipients and their fetuses and babies.

Death from Transfusion-Transmitted Anaplasmosis, New York, USA, 2017.

We report a death from transfusion-transmitted anaplasmosis in a 78-year-old man. The patient died of septic shock 2 weeks after a perioperative transfusion with erythrocytes harboring Anaplasma phagocytophilum. The patient's blood specimens were positive for A. phagocytophilum DNA beginning 7 days after transfusion; serologic testing remained negative until death.

The Development of a Social Networking-Based Relatedness Intervention Among Young, First-Time Blood Donors: Pilot Study.

BACKGROUND: Increasing repeat blood donation behavior is a critical public health goal. According to self-determination theory, the process of developing internal motivation to give blood and an associated self-identity as a blood donor may be promoted by feelings of "relatedness" or a connection to other donors, which may be enhanced through social relations and interactions. OBJECTIVE: The purpose of this report it to describe the development and pilot testing of a social networking-based (Facebook) intervention condition designed to increase feelings of relatedness via virtual social interaction and support. METHODS: To develop the intervention condition content, images, text, polls, and video content were assembled. Ohio University college students (N=127) rated the content (82 images/text) presented by computer in random order using a scale of one to five on various dimensions of relatedness. Mean ratings were calculated and analyses of variance were conducted to assess associations among the dimensions. Based on these results, the relatedness intervention was adapted and evaluated for feasibility, acceptability, and preliminary efficacy among 24 first-time donors, aged 18 to 24 years, in a 30-day pilot trial. Paired t-tests were conducted to examine change over time in relatedness and connectedness. RESULTS: The intervention condition that was developed was acceptable and feasible. Results of the uncontrolled, preintervention, and postintervention evaluation revealed that feelings of individual-level relatedness increased significantly after the intervention. CONCLUSIONS: By promoting first-time blood donor relatedness, our goal is to enhance internal motivation for donating and the integration of the blood donor identity, thus increasing the likelihood of future repeat donation. TRIAL REGISTRATION: ClinicalTrials.gov NCT02717338; https://clinicaltrials.gov/ct2/show/NCT02717338 (Archived by WebCite at http://www.webcitation.org/6ymHRBCwu)

Transfusion-transmitted and community-acquired babesiosis in New York, 2004 to 2015.

BACKGROUND: Babesiosis is a potentially life-threatening zoonotic infection most frequently caused by the intraerythrocytic parasite Babesia microti. The pathogen is usually tickborne, but may also be transfusion or vertically transmitted. Healthy persons, including blood donors, may be asymptomatic and unaware they are infected. Immunocompromised patients are at increased risk for symptomatic disease. STUDY DESIGN AND METHODS: All reported community-acquired babesiosis cases in New York from 2004 to 2015 were evaluated, enumerated, and characterized. All potential transfusion-transmitted babesiosis (TTB) cases reported through one or more of three public health surveillance systems were investigated to determine the likelihood of transfusion transmission. In addition, host-seeking ticks were actively collected in public parks and other likely sites of human exposure to B. microti. RESULTS: From 2004 to 2015, a total of 3799 cases of babesiosis were found; 55 (1.4%) of these were linked to transfusion. The incidence of both community-acquired babesiosis and TTB increased significantly during the 12-year study period. The geographic range of both ticks and tickborne infections also expanded. Among TTB cases, 95% of recipients had at least one risk factor for symptomatic disease. Implicated donors resided in five states, including in 10 New York counties. More than half of implicated donors resided in counties known to be B. microti endemic. CONCLUSION: The increasing incidence of TTB correlated with increases in community-acquired babesiosis and infection of ticks with B. microti. Surveillance of ticks and community-acquired cases may aid identification of emerging areas at risk for Babesia transfusion transmission.