West Nile Virus Emergence in Germany 2019: Looking for Hidden Human West Nile Virus Infections.

Background: Autochthonous human West Nile virus (WNV) infections were notified in the infectious disease surveillance system in Germany in 2018 for the first time and every year since then. Since clinically apparent infections are infrequent, we conducted two studies to investigate subclinical infections of this emerging disease in Germany in 2019 to detect infections not visible to surveillance based on symptomatic infections: limited-scope blood donor testing and a serosurvey among employees at two Berlin zoos with a history of demonstrated WNV infections in animals. Methods: For the zoo study, employees of the two zoos in Berlin were invited to participate in the study in late 2019. Blood samples were drawn and tested for the presence of antibodies (immunoglobulin M [IgM] and immunoglobulin G [IgG]) against WNV, and two other flaviviruses present in Germany: Usutu virus and Tick-borne encephalitis virus (TBEV). For the study in blood donors, four blood establishments with collection sites in regions with documented WNV-infected animals in 2018 and 2019 participated in the study. All donations in these regions were tested for WNV genome from July to November 2019. Results: In the enzyme-linked immunosorbent assay, none of the 70 tested zoo employees were WNV IgM-positive, 8 were WNV IgG-positive, additional 2 participants had equivocal results. All 10 were negative in the virus neutralization test (VNT) for WNV, but positive in the VNT for TBEV. None of the 4273 samples from blood donors tested in areas with WNV-infected animals was positive for WNV-RNA. Conclusion: Our results indicate that WNV circulation in Germany, though clearly documented in animals in 2019, apparently affected very few humans. Still areas with WNV-positive animals remain risk areas for human infection as well.

HemoCue Hb-801 Provides More Accurate Hemoglobin Assessment in Blood Donors Than OrSense NBM-200.

Hemoglobin levels are commonly assessed to prevent causing or worsening of anemia in prospective blood donors. We compared head-to-head the accuracy of different technologies for measuring hemoglobin suitable for use in mobile donation units. We included 144 persons donating platelets at the Central Institute for Blood Transfusion and Immunology in Innsbruck, Austria. Hemoglobin levels were measured in venous blood using the portable hemoglobinometer HemoCue Hb-801 and noninvasively using OrSense NBM-200, and compared to values obtained with the Sysmex XN-430, an automated hematology analyzer employing the sodium lauryl sulphate method, which is broadly used as reference method in everyday clinical practice. Mean age of participants was 34.2 years (SD 13.0); 34.0% were female. Hemoglobin values measured with HemoCue were more strongly correlated with the Sysmex XN-430 (r = 0.90 [95% CI: 0.87-0.93]) than measured with OrSense (r = 0.49 [0.35-0.60]). On average, HemoCue overestimated hemoglobin by 0.40 g/dL (0.31-0.48) and OrSense by 0.75 g/dL (95% CI: 0.54-0.96). When using OrSense, we found evidence for higher overestimation at higher hemoglobin levels (proportional bias) specifically in females but not in males (Pdifference = .003). Sensitivity and specificity for classifying donors according to the hemoglobin donation thresholds were 99.2% (95% CI: 95.3%-100.0%) and 43.8% (23.1%-66.8%) for HemoCue vs 95.3% (89.9%-98.0%) and 12.5% (2.2%-37.3%) for OrSense. Areas under the receiver operating characteristic curves were higher using HemoCue vs OrSense both in females (0.933 vs 0.547; P = .044) and males (0.948 vs 0.628; P < .001). HemoCue Hb-801 measures hemoglobin more accurately than OrSense NBM-200 in the setting of mobile blood donation units. Our findings are particularly relevant for females, having in mind that anemia is more prevalent in females than in males.

The return rate of deferred blood donors in Iran.

BACKGROUND AND OBJECTIVES: The process of selecting blood donors is crucial for keeping the health of donors and ensuring the safety of the blood supply. However, it may create unpleasant feeling in those who are deferred. In this study, we aim to explore the return rates of Iranian deferred donors in comparison with eligible donors. MATERIALS AND METHODS: The study included all whole blood donors referred between March 2017 and March 2018, who experienced temporary deferral for any reason. Donors who successfully donated blood during this period were also part of the study. Participants were followed up until their next donation attempt, spanning 4.8 years after initial inclusion. Then odds of return and median return time for both deferred and eligible donors were calculated. RESULTS: From 993,824 volunteers, 733,153 (73.77%) were eligible and 192,332 (19.35%) temporary deferred. The return rate in the eligible and deferred donors was 74.77% vs. 51.77%, respectively (OR:2.78; 99%CI: 2.71-2.81). Odds of return among deferred regular (OR=7.02, 99%CI:6.64-7.42), men (OR: 2.57, 99%CI:2.45-2.69), and over 45 years (OR: 1.15, 99% CI: 1.09-1.20), was higher than first-time, women, and younger donors. The median return time for eligible and deferred donors was 315 (99%CI: 313-316) and 1,467(99%CI: 1,412-1,524) days, respectively. CONCLUSION: This study revealed the negative effect of deferral on the return rate, that led to a 23% reduction in the return of deferred donors. Avoiding unnecessary deferral through adherence to the standard operating procedure of donor selection and effective counselling which clarifies the purpose of deferral and encourages them to return after the deferral period ends are recommended.

Effects of heat waves and cold spells on blood parameters: a cohort study of blood donors in Tianjin, China.

BACKGROUND: With the increasing occurrence of extreme temperature events due to climate change, the attention has been predominantly focused on the effects of heat waves and cold spells on morbidity and mortality. However, the influence of these temperature extremes on blood parameters has been overlooked. METHODS: We conducted a cohort study involving 2,752 adult blood donors in Tianjin, China, between January 18, 2013, and June 25, 2021. The generalized additive mixed model was used to investigate the effects and lagged effects of heat waves and cold spells on six blood parameters of blood donors, including alanine aminotransferase (ALT), white blood cell count (WBC), red blood cell count (RBC), hemoglobin (HB), hematocrit (HCT), and platelet count (PLT). Subgroup analyses were stratified by sex, age, and BMI. RESULTS: Heat waves and cold spells are associated with changes in blood parameters, particularly HB and PLT. Heat waves increased HB and PLT, while cold spells increased HB and decreased PLT. The effect of heat waves is greater than that of cold spells. The largest effect of heat waves on HB and PLT occurred at lag1 with 2.6 g/L (95% CI: 1.76 to 3.45) and lag7 with 9.71 × 10^9/L (95% CI: 6.26 to 13.17), respectively, while the largest effect of cold spells on HB and PLT occurred at lag0 with 1.02 g/L (95% CI: 0.71 to 1.33) and lag2 with -3.85 × 10^9/L (95% CI: -5.00 to -2.70), respectively. In subgroup analysis, the effect of cold spells on ALT was greater in the 40-49 age group. CONCLUSION: We indicated that heat waves and cold spells can impact hemoglobin and platelet counts in the human body. These findings provide evidence linking heat waves or cold spells to diseases and may reduce health risks caused by extreme temperature events.

Discussion on the recruitment strategy for apheresis platelet donors in Chongqing during a public health emergency.

Objective: This study aimed to analyze the population characteristics of apheresis platelet donors in Chongqing Province and provide a scientific basis for the development of precise and efficient recruitment strategies. The ultimate goal is to increase the number of regular platelet donors in preparation for public health emergencies. Methods: This study involved 53,089 blood donors who donated apheresis platelets to the Chongqing Blood Center from 2020 to 2022. Data regarding age, sex, blood type, education level, occupation, and frequency of blood donation were collected and analyzed to identify factors influencing platelet donation. Results: Between 2020 and 2022, the majority of apheresis platelet donors in Chongqing were aged 25-35 years, with a male-to-female ratio of 2.6:1. The ABO blood group distribution was O > A > B > AB. The apheresis platelet donors mainly consisted of college students, and the donors who had donated only once accounted for the greatest proportion. Conclusion: Based on the population characteristics of apheresis platelet donors in Chongqing, blood collection and supply organizations must refine emergency blood collection and supply plans during public health emergencies. This study underscores the importance of developing precise and efficient recruitment strategies for apheresis platelet donors and expanding the pool of regular apheresis platelet donors. These measures are essential to ensure the timely, safe, and effective use of clinical blood resources during public health emergencies.

Changes in transfusion-transmissible infection prevalence and demographics among US blood donors during the COVID-19 pandemic.

BACKGROUND: The COVID-19 pandemic impacted the US blood supply. We compared blood donor demography and infectious disease prevalence before and during the pandemic using a large multicenter database. METHODS: Data were categorized as "Before COVID-19" (March 2018-February 2020) or "During COVID-19" (March 2020-February 2022). Donor demographics, donation frequency, and infectious marker prevalence of HIV, HBV, and HCV were compared for the two time periods. The odds of a donor testing positive for these infections among the two time periods were calculated using multivariable logistic regression. RESULTS: Our study assessed a total of 26,672,213 donations including 13,430,380 before and 13,241,833 during COVID-19. There were significantly more donations from donors who were female, aged 40 and older, white, and repeat, during COVID-19. Donation frequency comparison quantified the increase in donations from donors who were white, female, older, and repeat during the pandemic. The prevalence of HIV and HCV decreased significantly during COVID-19 compared to before, but not for HBV. For HIV, the adjusted odds of infection during the pandemic did not differ but for HBV, the odds were significantly more likely during the pandemic and were significantly lower for HCV. DISCUSSION: Demographics and infectious disease marker prevalence changed during the COVID-19 pandemic in the United States. Prevalence of each infection in the donor population will continue to be monitored to determine if changes were specific to the pandemic period.

Arbovirus - a threat to transfusion safety in Spain: a narrative review. / Arbovirus como amenaza para la seguridad transfusional en España: revisión narrativa.

Arboviruses represent a threat to transfusion safety for several reasons: the presence of vectors and the notification of autochthonous cases in our region, the recent increase in the number of cases transmitted through blood and/or blood component transfusion, the high prevalence rates of RNA of the main arboviruses in asymptomatic blood donors, and their ability to survive processing and storage in the different blood components. In an epidemic outbreak caused by an arbovirus in our region, transfusion centres can apply different measures: reactive measures, related to donor selection or arbovirus screening, and proactive measures, such as pathogen inactivation methods. The study of the epidemiology of the main arboviruses and understanding the effectiveness of the different measures that we can adopt are essential to ensure that our blood components remain safe.

Anti-SARS-CoV-2 IgG Seroprevalence in Tyrol, Austria, among 28,768 Blood Donors between May 2022 and March 2023.

BACKGROUND: To provide updated estimates on SARS-CoV-2 antibody seroprevalence and average antibody titres for Central Europe. METHODS: In repeat cross-sectional investigations (1 May 2022 to 9 March 2023) involving 28,768 blood donors in the Federal State of Tyrol, Austria (participation rate: 87.0%), we measured Spike receptor-binding domain (RBD) and Nucleocapsid IgG antibodies (37,065 and 12,645 samples), and estimated monthly seroprevalences and geometric mean titres. RESULTS: Median age of participants was 45.4 years (range 18-70); 43.2% were female. Spike RBD IgG antibody seroprevalence was 96.3% (95% CI: 95.6-96.9%) in May 2022, 97.4% (96.7-98.0%) in December 2022, and 97.9% (96.4-98.8%) in March 2023. Among seropositive participants, geometric mean titres increased from 1400 BAU/mL (95% CI: 1333-1471) in May 2022 to 1821 BAU/mL (1717-1932) in December 2022, and dropped to 1559 BAU/mL (1405-1729) by March 2023. Furthermore, titres differed markedly by vaccination status and history of infection, with being the highest in participants with booster vaccination and prior infection. In autumn 2022, Nucleocapsid IgG antibody seroprevalence ranged from 36.5% (35.0-38.1) in September to 39.2% (37.2-41.2) in December 2022. CONCLUSION: Seroprevalence of SARS-CoV-2 antibodies in blood donors from Tyrol, Austria, was remarkably stable from May 2022 to March 2023. In contrast, average Spike RBD IgG antibody titres peaked in December 2022.

The prevalence of occult hepatitis B infection among the blood donors in a donation center in Beijing.

Occult HBV infection (OBI) remains a potential threat for blood safety. The prevalence of OBI was investigated in a blood donation center of Chinese PLA General Hospital to improve HBV blood safety. 229446 samples from blood donors were screened by two different enzyme-linked immunosorbent assay (ELISA) kits. 78 samples were HBV DNA positive among 212134 ELISA nonreactive donor samples. The prevalence of OBI was 0.04% (76/212134). Ten samples of OBI were permitted by the donors' content for further research, and all of these were below 200IU/mL, and six of these were below 20IU/mL(6/10,60%). Genotype B and genotype C was 20% (2/10) and 80% (8/10), respectively. 16 amino acid mutations were detected in the S region of OBI, included three mutations in MHR region of S. The prevalence of OBI is rare in this donation center. These mutations we found may contribute to the multifactorial occurrence of OBI.

Evaluation of new haematology analyser, XN-31, for malaria detection in blood donors: A single-centre study from India.

BACKGROUND AND OBJECTIVES: Malaria continues to be a significant public health concern in India, with several regions experiencing endemicity and sporadic outbreaks. The prevalence of malaria in blood donors, in India, varies between 0.02% and 0.07%. Common techniques to screen for malaria, in blood donors and patients, include microscopic smear examination and rapid diagnostic tests (RDTs) based on antigen detection. The aim of this study was to evaluate a new fully automated analyser, XN-31, for malaria detection, as compared with current practice of using RDT. MATERIALS AND METHODS: Cross-sectional analytical study was conducted to evaluate clinical sensitivity and specificity of new automated analyser XN-31 among blood donors' samples and clinical samples (patients with suspicion of malaria) from outpatient clinic collected over between July 2021 and October 2022. No additional sample was drawn from blood donor or patient. All blood donors and patients' samples were processed by malaria rapid diagnostic test, thick-smear microscopy (MIC) and the haematology analyser XN-31. Any donor blood unit incriminated for malaria was discarded. Laboratory diagnosis using MIC was considered the 'gold standard' in the present study. Clinical sensitivity and specificity of XN-31 were compared with the gold standard. RESULTS: Fife thousand and five donor samples and 82 diagnostic samples were evaluated. While the clinical sensitivity and specificity for donor samples were 100%, they were 96.3% and 100% for diagnostic samples. CONCLUSION: Automated haematology analysers represent a promising solution, as they can deliver speedy and sensitive donor malaria screening assessments. This method also has the potential to be used for pre-transfusion malaria screening along with haemoglobin estimation.

A novel multiplex real-time PCR assay for the detection of cytomegalovirus, Epstein-Barr virus, herpes simplex virus 1/2 and strategies for application to blood screening.

A multiplex real-time PCR has been developed to simultaneously detect transfusion-transmissible pathogens cytomegalovirus, Epstein-Barr virus and herpes simplex virus, as well as to provide sample quality testing, for the conserved regions of the cytomegalovirus UL123 gene, the Epstein-Barr virus BKRF1 gene, and the herpes simplex virus 1/2 UL30 gene, tested on 500 blood donors and 320 transfusion recipients. The laboratory sensitivities for all 3 pathogens were 100 copies/µL. Compared to the commercial real-time PCR reference kit, the multiplex real-time PCR assay for the detection of CMV, EBV and HSV presented 100% consistency. In 820 whole blood samples, the multiplex real-time PCR assay identified 34 (4.15%) positive for CMV DNA, 15 (1.83%) positive for EBV DNA, and 6 (0.73%) positive for HSV DNA. For blood transfusions in high-risk groups, whole blood herpes virus test should be included in the spectrum of pathogen testing for blood donors and recipients.

Knowledge and practices regarding leishmaniasis in Portugal - Comparison between blood donors and health students/professionals.

Objective: To compare the current knowledge and practices regarding leishmaniasis among blood donors and health students and professionals, in Portugal. Material and methods: Data were collected through the application of two questionnaires (one online and one in paper) with similar questions in two distinct cross-sectional independent studies, each targeting one of the groups. Descriptive statistics and hypothesis testing were performed using IBM® SPSS® Statistics. Results: In total, 3763 blood donors, 254 students and 232 professionals were included in the comparative analysis. Over 95% of students and professionals, but only around 70% of blood donors had previously heard of leishmaniasis. Over 90% of participants in each group admitted leishmaniasis affected animals, but only in the professional group over 90% were aware of human leishmaniasis. Conclusions: Even though canine leishmaniasis is recognized by many blood donors and by most students and professionals, awareness of the disease in humans is less common, highlighting the importance of promoting an approach to this infection through a One Health lens.

Toxoplasma gondii seroprevalence in the Iranian blood donors: A systematic review and meta-analysis.

Background: The present systematic review and meta-analysis was done to assess the rate of Toxoplasma gondii (T. gondii) exposure among Iranian healthy blood donors. Methods: We searched four English (PubMed, Scopus, Web of Science, and Science Direct) and two Persian databases (Magiran and SID) as well as Google Scholar as a specialized article search engine using specific keywords for relevant papers from the inception up to November 30, 2023. Results: In total, 19 studies enrolling 8226 apparently healthy blood donors were examined regarding T. gondii-specific IgG and/or IgM antibodies, among which 2666 [32.9% (95% CI: 25.3%-41.6%)], 168 [1.4% (95% CI: 0.9%-2.1%)], and 83 [1.7% (95% CI: 1.3%-2.1%)] subjects were seropositive regarding IgG, IgM, and both IgG/IgM antibodies, respectively. Five risk factors were significantly associated with T. gondii seroprevalence, including gender (OR = 1.98; 95% CI: 1.52-2.58; P < 0.001), contact with cat (OR = 2.41; 95% CI: 1.70-3.41; P < 0.001), contact with soil (OR = 2.83; 95% CI: 1.07-7.45; P = 0.035), consuming raw/undercooked meat (OR = 1.95; 95% CI: 1.03-3.70; P = 0.039), and raw/unwashed vegetables (OR = 1.70; 95% CI: 1.25-2.31; P = 0.001). Conclusion: A moderate rate of T. gondii exposure was found in the Iranian blood donors, with the association of several risk factors, including gender, contact with cat, contact with soil, consumption of unwashed vegetables and/or undercooked meat. Still, more studies are recommended regarding T. gondii exposure among blood donors in Iran.

Comparative evaluation of rapid plasma reagin and ELISA with Treponema pallidum hemagglutination assay for the detection of syphilis in blood donors: a single center experience.

INTRODUCTION: The prime responsibility of blood transfusion services in India is to provide safe blood. The donated blood is tested for human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), malaria and syphilis. In India, the screening of donated blood for syphilis is performed by rapid plasma reagin (RPR) or venereal disease research laboratory (VDRL), whereas the World Health Organization (WHO) recommends screening of syphilis in blood donors by enzyme-linked immunosorbent assay (ELISA). Therefore, the aim of this study was to evaluate the performance of RPR and ELISA with the Treponema pallidum hemagglutination assay (TPHA - the gold standard) for the detection of syphilis in blood donors. METHODS: In this cross-sectional study, 1524 consecutive whole blood donors were screened from April to October 2022. All blood samples collected during the study period were tested by RPR, ELISA and the TPHA and the results obtained were compared. RESULTS: The seroprevalence of syphilis in blood donors in this study was 0.06% by RPR and 0.72% by ELISA and TPHA. On considering ELISA and the TPHA as the gold standard, ELISA had comparable sensitivity (100%), a higher specificity (100% vs. 99.34%), a higher positive predictive value (PPV - 100% vs. 9.1%) and no biological false positive/false negative results (0 vs. 10 false negatives) when compared to RPR. CONCLUSION: ELISA performed better as a screening assay than RPR in the detection of syphilis in blood donors, which is in agreement with the WHO recommendations for syphilis testing in blood donors with low prevalence.

Investigation of serum level relationship of pro-inflammatory and anti-inflammatory cytokines with vitamin D among healthy Ghanaian population.

BACKGROUND: The interplay between vitamin D status and inflammatory cytokines in a supposedly sufficient sunshine environment has not well been evaluated. The study sought to determine their association. METHODS: This cross-sectional study involved 500 healthy adult blood donors from some selected hospitals in Ghana enrolled from June to November 2016. Venous blood samples were obtained from participants, 25(OH)D, TNF-alpha, IFN-gamma, and IL 10 were measured using enzyme linked immunosorbent assay (ELISA) technique. Serum levels of 25(OH)D < 20ng/ml were classified as being deficient or low. RESULTS: The average age of the participants was 27.97 years. No statistically significant association was established between 25(OH) D status, mean age (p = 0.1693), and gender (p = 0.5461) of study participants. Similarly, the median 25(OH) D (p = 0.8392), IL-10 (p = 0.5355), TNF-alpha (p = 0.9740), and IFN-gamma (p = 0.6908) were not significantly different across gender. There was a significantly increased levels of TNF-alpha (p < 0.0001) and IFN-gamma (p < 0.0001) among participants with 25(OH) D deficiency compared to those without deficiency. Concurrently, participants with 25(OH)D deficiency had a significantly reduced levels of IL-10 (p < 0.0001) compared to those without 25 (OH) D deficiency. The most accurate biochemical markers for identifying 25 (OH) D deficiency were IFN-gamma (AUC = 0.879; p < 0.0001) followed by TNF-gamma (AUC = 0.849; p < 0.0001) and IL-10 (AUC = 0.707; p < 0.0001). CONCLUSION: There was a significant association between vitamin D levels and pro-inflammatory cytokines (TNF-alpha, IFN-gamma) and anti-inflammatory cytokine (IL 10) among healthy Ghanaian populace.

Exploration of the Healthy Donor Effect Among 0.6 Million Blood Donors in China: Longitudinal Study.

BACKGROUND: The World Health Organization emphasizes the importance of completely voluntary blood donation to maintain safe and sustainable blood supplies. However, the benefits of blood donation for donors, such as reducing the risk of disease, remain a topic of debate due to the existence of the healthy donor effect (HDE). This effect arises because of inherent health differences between blood donors and the general population, and it is also considered a methodological issue. OBJECTIVE: This study aims to generate a more detailed health profile of blood donors from a donor cohort study to mitigate and quantify the HDE and properly interpret the association between blood donation and disease outcomes among blood donors. METHODS: A retrospective cohort study was conducted between January 2012 and December 2018 among donors before their first donation. One-to-one propensity score matching was conducted through a random selection of individuals without any history of blood donation, as reported from their electronic health records. We conducted a Poisson regression between blood donors and non-blood donors before the first donation to estimate the adjusted incidence rate ratio (AIRR) of selected blood donation-related diseases, as defined by 13 categories of International Classification of Diseases, Tenth Revision (ICD-10) codes. RESULTS: Of the 0.6 million blood donors, 15,115 had an inpatient record before their first donation, whereas 17,356 non-blood donors had an inpatient record. For the comparison between blood donors and the matched non-blood donors, the HDE (the disease incidence rate ratio between non-blood donors and blood donors) was an AIRR of 1.152 (95% CI 1.127-1.178; P<.001). Among disease categories not recommended for blood donation in China, the strongest HDE was observed in the ICD-10 D50-D89 codes, which pertain to diseases of the blood and blood-forming organs as well as certain disorders involving the immune mechanism (AIRR 3.225, 95% CI 2.402-4.330; P<.001). After age stratification, we found that people who had their first blood donation between 46-55 years old had the strongest HDE (AIRR 1.816, 95% CI 1.707-1.932; P<.001). Both male and female donors had significant HDE (AIRR 1.082, 95% CI 1.05-1.116; P=.003; and AIRR 1.236, 95% CI 1.196-1.277; P<.001, respectively) compared with matched non-blood donors. CONCLUSIONS: : Our research findings suggest that the HDE is present among blood donors, particularly among female donors and those who first donated blood between the ages of 46 and 55 years. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2200055983; https://www.chictr.org.cn/showproj.html?proj=51760.

Mitigating the impact of blood shortages in England.

The supply of blood components and products in sufficient quantities is key to any effective health care system. This report describes the challenges faced by the English blood service, NHS Blood and Transplant (NHSBT), towards the end of the COVID-19 pandemic, which in October 2022 led to an Amber Alert being declared to hospitals indicating an impending blood shortage. The impact on the hospital transfusion services and clinical users is explained. The actions taken by NHSBT to mitigate the blood supply challenges and ensure equity of transfusion support for hospitals in England including revisions to the national blood shortage plans are described. This report focuses on the collaboration and communication between NHSBT, NHS England (NHSE), Department of Health and Social Care (DHSC), National Blood Transfusion Committee (NBTC), National Transfusion Laboratory Managers Advisory Group for NBTC (NTLM), National Transfusion Practitioners Network, the medical Royal Colleges and clinical colleagues across the NHS.

Breakthrough infection by hepatitis B virus in a vaccinated blood donor: An emerging threat for transfusion safety in low-endemic countries?

We present the case of a breakthrough infection by hepatitis B virus (HBV), intending to warn about the challenge that HBV represents for transfusion safety. Virological markers for HBV infection were assayed during a blood donor screening by detection of HBsAg, anti-HBc, and viral nucleic acid (HBV DNA) by a nucleic acid test (NAT). Additionally, samples were analyzed for detection of immunoglobulin M anti-HBc, HBeAg, anti-HBe, and anti-HBs. A first-time donor repeatedly tested positive for HBV DNA by NAT and nonreactive for HBV-serological markers of infection. He stated having completed the anti-HBV vaccination schedule; thus, study of anti-Hbs resulted in reactive at protective level (18 mIU/mL). The donor denied clinical symptoms of hepatitis and remained healthy during the follow-up period. 95 days postdonation, NAT was negative, seroconversion of anti-HBc ab was detected, and a significant increase in anti-HBs concentration was measured (>1000 mIU/mL). This is the first case of HBV-breakthrough infection reported in Argentina and to our knowledge, this potential threat to transfusion safety is novel in an HBV low-endemic region with high coverage of HBV vaccination. The occurrence of breakthrough infections challenges the current protocols for the identification of HBV-infected subjects, could be a source of silent HBV transmission.

A case-control study of risk factors for incident hepatitis B virus infection in South African blood donors.

OBJECTIVES: Hepatitis B virus (HBV) infection remains a global health problem. Risk factors for HBV infection are usually assessed in prevalent rather than incident infections. To identify demographic and behavioral risks associated with incident HBV among South African blood donors. METHODS: A case-control study was performed between November 2014 and January 2018. Cases were blood donors testing positive for HBV DNA with or without hepatitis B surface antigen but negative for antibody to hepatitis B core antigen. Participants completed an audio computer-assisted structured interview on exposures during the previous 6 months. Sex-specific multivariable logistic regression yielded independent associations between risks and HBV infection. RESULTS: 56 females and 37 males with incident HBV were compared to 438 female and 439 male controls, respectively. For females, risk factors were accepting money or goods for sex, using agents to prepare one's anus prior to anal sex, penetrating injury, non-Black race, and lower educational status. Men reporting homosexual or bisexual orientation or sex with other men, previous injury, referral for HBV testing, or lack of medical insurance were at increased risk. For both sexes, having more than two male sexual partners increased risk. CONCLUSIONS: Sexual behaviors predominated over parenteral exposures as risks for incident HBV in both female and male blood donors.