Parvovirus B19: What Is the Relevance in Transfusion Medicine?

Increased parvovirus B19 seropositivity in healthy blood donors in India

A core component of every blood program is the supply of safe blood and blood products. The elevated risk of transmission through these products is due to parvovirus B19 (B19V) resistance to the virus inactivation procedures. Our study aimed to screen asymptomatic blood donors for B19V at a tertiary care hospital in Chennai, Tamil Nadu, between September 2020 and June 2021. Sera from 106 healthy blood donors who tested negative for Human immunodeficiency virus (HIV), Hepatitis B surface antigen (HBsAg), Hepatitis C virus (HCV), syphilis, and malaria were tested for anti-B19V IgM and IgG using a qualitative indirect enzyme-linked immunosorbent assay (ELISA). In the study population, 23.5% (n = 25) of donors tested IgM positive, 38.6% (n = 41) tested IgG positive, and 7.5% (n = 8) tested positive for both IgM and IgG. A proportion of 61.3% (n = 65) of the blood donors tested IgG negative, suggesting they had no past B19V infection. B19V DNA was not detected in any of the subjects. The high seroprevalence of IgM indicates that blood donors may have been recently exposed to B19V, potentially posing a risk to immunocompromised individuals and those with hematological stress. Further longitudinal studies with a larger sample size are recommended to better understand the risk of B19V transfusion transmission.

Detection and analysis of parvovirus B19 among blood donors in a regional blood center in Eastern China

Background and objective

The B19 virus is mainly transmitted through the respiratory tract; however, studies have shown that it can also be transmitted through blood transfusions or plasma products. This study investigated B19V antibodies, DNA, and gene typing in blood donors at a central blood station in China to evaluate the status of B19V infection.

Materials and methods

A total of 7728 samples from Suzhou Blood Center were collected from July 2022 to April 2023. Samples were detected for the B19V DNA using real-time polymerase chain reaction. Furthermore, 893 selected samples were screened for the seroprevalence of B19V antibodies using enzyme-linked immunosorbent assay. The NS1-VP1u fragment of the B19V DNA-positive samples was amplified using nested PCR, and the sequences were determined. A B19V phylogenetic tree was constructed using neighborhood joint and maximum parsimony methods to discriminate genotypes using the NS1-VP1u sequences.

Results

The percentages of IgG, IgM, and DNA were 19.4 %, 1.9 %, and 0.09 %, respectively. IgG positivity increased with age, and there was a significant difference among the blood groups. The IgG levels of repeat donors were greater than those of first-time donors. There were no apparent differences in the IgM levels in all the participants. Genotyping revealed that the B19 genotype was 1.

Conclusions

The prevalence of B19V antibodies and DNA was lower in these areas than in rest of China, indicating that the risk of B19V transmission via transfusion may be relatively low. However, during transfusion, particular attention should be paid to the B19V-susceptible populations, especially those in high-risk groups.

Epigenetic clocks and gliomas: unveiling the molecular interactions between aging and tumor development

Gliomas, the most prevalent and aggressive primary brain tumors, represent a diverse group of malignancies originating from glial cells. These tumors account for significant brain tumor-related morbidity and mortality, with higher incidence rates in North America and Europe compared to Asia and Africa. Genetic predispositions and environmental factors, particularly ionizing radiation, critically impact glioma risk. Epigenetics, particularly DNA methylation, plays a pivotal role in glioma research, with IDH-mutant gliomas showing aberrant methylation patterns contributing to tumorigenesis. Epigenetic clocks, biomarkers based on DNA methylation patterns predicting biological age, have revealed significant insights into aging and tumor development. Recent studies demonstrate accelerated epigenetic aging in gliomas, correlating with increased cancer risk and poorer outcomes. This review explores the mechanisms of epigenetic clocks, their biological significance, and their application in glioma research. Furthermore, the clinical implications of epigenetic clocks in diagnosing, prognosticating, and treating gliomas are discussed. The integration of epigenetic clock data into personalized medicine approaches holds promise for enhancing therapeutic strategies and patient outcomes in glioma treatment.

Transfusion-Transmitted Disorders 2023 with Special Attention to Bone Marrow Transplant Patients

Transfusion medicine is traditionally a strong/fundamental part of clinical practice, saving hundreds of millions of lives. However, blood-borne or transmitted infections are a well-known and feared possibility, a risk we relentlessly mitigate. Pathogens are continuously and rather quickly changing, so during the last decade, many, sometimes exotic, new pathogens and diseases were recorded and analyzed, and some of them were proved to be transmitted with transfusions. Blood or blood component transfusions are carried out after cautious preparative screening and inactivation maneuvers, but in some instances, newly recognized agents might escape from standard screening and inactivation procedures. Here, we try to focus on some of these proven or potentially pathogenic transfusion-transmitted agents, especially in immunocompromised patients or bone marrow transplantation settings. These pathogens are sometimes new challenges for preparative procedures, and there is a need for more recent, occasionally advanced, screening and inactivation methods to recognize and eliminate the threat a new or well-known pathogen can pose. Pathogen transmission is probably even more critical in hemophiliacs or bone marrow transplant recipients, who receive plasma-derived factor preparations or blood component transfusions regularly and in large quantities, sometimes in severely immunosuppressed conditions. Moreover, it may not be emphasized enough that transfusions and plasma-derived product administrations are essential to medical care. Therefore, blood-borne transmission needs continued alertness and efforts to attain optimal benefits with minimized hazards.

Prevalence of anti-parvovirus B19 IgG and IgM and parvovirus B19 viremia in pregnant women in an urban area of Northern Italy

Parvovirus B19 (B19V) infection in pregnancy is mostly asymptomatic, but can cause complications including abortion and fetal hydrops. Although its infection is ubiquitous, seroprevalence among pregnant women varies according to different geographical areas. Since seroprevalence data in Italy are limited, the prevalence of antibodies and DNA in pregnant women was evaluated retrospectively, correlating the clinical situation of mothers and newborns. One thousand eight hundred and ninety-three sequential sera were examined from pregnant women (60.8% in the first trimester, 16.6% in the second one, and 22.6% in the third one, respectively) for anti-B19V IgG and IgM (confirmed by immunoblot); 1402 (74.1%) were of Italian origin and 491 (25.9%) non-Italian women. Molecular tests were used to search for viral genome. One thousand three hundred and fifteen (69.5%) samples were IgG-positive, 21 (1.1%) IgM-positive, and 578 (30.5%) nonimmune. The difference in IgG seroprevalence between Italian (71.1%) and non-Italian women (64.8%) was statistically significant. Of the 21 IgM-positive women, 16 were confirmed positive also by immunoblot (prevalence: 0.8%), of which 11 were viraemic (prevalence: 0.6%; mean 1.3 × 10⁴  geq/ml). Mothers were asymptomatic, and the newborns had no clinical signs of congenital infection. IgG seroprevalence in Italy is high, with differences between Italian women and non-Italian women from geographic areas with lower endemic levels of B19V. The consistent migratory flows in place could lead to an increase in the number of susceptible women. The prevalence of viremia is low, and has not been associated with evident fetal damage at birth.

Prevalence and Phylogenetic Analysis of Parvovirus (B19V) among Blood Donors with Different Nationalities Residing in Qatar

Human parvovirus (B19V) is the causative agent of erythema infectiosum in children and is linked to a wide range of clinical manifestations. Studies related to B19V prevalence in the Middle East and North Africa (MENA) region and other parts of Asia are very scarce. The objectives of this study were to estimate the seroprevalence (anti-B19V IgM and IgG), the viremia rate (B19V DNA), and the circulating genotypes of B19V among blood donors in Qatar. Methods: Donors’ blood samples (n = 5026) from different nationalities, mainly from the MENA region and South East Asia, were collected from 2014–2016. Samples were tested for the B19V DNA using RT-PCR. Furthermore, 1000 selected samples were tested to determine the seroprevalence of B19V antibodies using enzyme-linked immunosorbent assay (ELISA). Genotyping was performed on 65 DNA positive samples by sequencing of nested PCR fragments (NS1-VP1u region, 927 nt). Results: Only 1.4% (70/5026) of the samples had detectible B19V DNA in their blood. B19V DNA prevalence statistically decreased with age (p = 0.03). Anti-B19V IgG was detected in 60.3% (561/930) of the tested samples, while only 2.1% (20/930) were IgM-positive and 1.2% (11/930) were both IgM- and IgG-positive. B19V genotyping showed a predominance of Genotype 1 (100%). Sequence analysis of the NS1-VP1u region revealed 139 mutation sites, some of which were amino acid substitutions. Conclusion: Our results indicated a relatively high seroprevalence of B19V in Qatar. Most importantly, B19 DNA was detected among Qatari and non-Qatari blood donors. Therefore, blood banks in Qatar might need to consider screening for B19V, especially when transfusion is intended for high-risk populations, including immunocompromised patients.

PREVALENCE OF HUMAN PARVOVIRUS B19 IgG AND IgM ANTIBODIES AMONG PREGNANT WOMEN ATTENDING ANTENATAL CLINIC AT FEDERAL TEACHING HOSPITAL IDO-EKITI, NIGERIA

Background:

Human Parvovirus B19 (B19V) is a DNA virus, transmitted through respiratory secretions, hand-to-mouth-contact, blood transfusion and trans-placental transfer. It causes high mortality and morbidity in pregnant women, thus contributing to poor maternal and child health. B19V has been neglected due to dearth of epidemiological data. The aim of this study was to determine the sero-prevalence of Human Parvovirus B19 antibodies among pregnant women attending antenatal clinic at Federal Teaching Hospital Ido-Ekiti, Nigeria.

Materials and Methods:

This cross-sectional study enrolled pregnant women attending Federal Teaching Hospital Ido-Ekiti from January to May 2019 to obtain sero-epidemiological data. One hundred and twenty-two (122) consenting pregnant women were enrolled following institutional ethical approval. They were administered structured questionnaire and venous blood was collected in plain tubes for serum extraction. Sera samples were analyzed for IgG and IgM antibodies using the enzyme linked immunosorbent assay method. Percentages, median, chi-square and multivariate analysis were carried out using SPSS version 17.

Results:

The prevalence of IgG was 44.3% (54/122), IgM 41.8% (51/122), and IgG/IgM 28.7% (35/122) leaving 55.7% (68/122) of the population uninfected. The median age of participants was 22 (Interquartile range 18-25) years among which 36-45years had the highest prevalence which was not statistically significant (p=0.09 X² =4.75). There was association between miscarriage, still birth, history of blood transfusion and prevalence of Human Parvovirus B19 (p<0.05).

Conclusion:

There is a high Prevalence of B19V among pregnant women attending antenatal clinic in this study. This underscores the need for testing and immunization of pregnant women against B19V.

Human parvovirus B19-associated early postoperative acquired pure red cell aplasia in simultaneous pancreas-kidney transplantation: A case report

BACKGROUND

Acquired pure red cell aplasia (aPRCA) related to human parvovirus B19 (HPV B19) is rarely reported in simultaneous pancreas-kidney transplantation (SPKT) recipients; there has yet to be a case report of early postoperative infection. In this current study, we report the case of a Chinese patient who experienced the disease in the early postoperative period.

CASE SUMMARY

A 63-year-old man, with type 2 diabetes and end-stage renal disease, received a brain dead donor-derived SPKT. Immunosuppression treatment consisted of tacrolimus, prednisone, enteric-coated mycophenolate sodium (EC-MPS), and thymoglobulin combined with methylprednisolone as induction. The hemoglobin (Hb) level declined due to melena at postoperative day (POD) 3, erythropoietin-resistant anemia persisted, and reticulocytopenia was diagnosed at POD 20. The bone marrow aspirate showed decreased erythropoiesis and the presence of giant pronormoblasts at POD 43. Metagenomic next-generation sequencing (mNGS) of a blood sample identified HPV B19 infection at POD 66. EC-MPS was withdrawn; three cycles of intravenous immunoglobulin (IVIG) infusion therapy were administered; and tacrolimus was switched to cyclosporine. The HPV B19-associated aPRCA resolved completely and did not relapse within the 1-year follow-up period. The diminution in mNGS reads was correlated with Hb and reticulocyte count improvements.

CONCLUSION

HPV B19-associated aPRCA can occur at an early period after SPKT. An effective therapy regimen includes IVIG infusion and adjustment of the immuno-suppressive regimen. Moreover, mNGS can be used for the diagnosis and to reflect disease progression.

Serological detection of human parvovirus B19 infection and associated risk factors among pregnant women in Jigawa State, Nigeria

Human Parvovirus B19 (B19 V) infection is hyperendemic in Nigeria. Pregnant women are not classically immunocompromised but maybe physiologically immunosuppressed and susceptible to viral infection. However, there is a paucity of studies on the epidemiology of B19V in Jigawa State, Northwestern Nigeria. This study aims to determine the seroprevalence, sociodemographic, and risk factors of human B19V infection among present women attending antenatal clinics of Jahun General Hospital, Nigeria. Between 2 February and 30 June 2019, blood samples were collected from 200 consented pregnant women and analyzed for anti-B19V IgM and IgG using commercially available enzyme-linked immunosorbent assay (ELISA). Sociodemographic and risk factors of subjects were collated through pre-tested structured questionnaires. Data generated were statistically analyzed for the association of anti-B19V and subjects' variables studied. Overall, the seroprevalence of anti-B19V IgM and IgG among pregnant women attending antenatal clinics of Jahun General Hospital, Nigeria was 6.0% and 22.5%, respectively. There was no significant association between the seroprevalence of anti-B19V IgM and anti-B19V IgG with all the sociodemographic variables and risk factors of pregnant women (P ˃0.05). However, pregnant women with a history of blood transfusion had a significant risk associated with seroprevalence of B19V IgM (OR = 5.95; 95% CI: 1.96-22.76; P = .009). Findings from this study revealed that a high proportion of the pregnant women were susceptible to B19V infection and anti-B19V IgG immunity decreased with age. Given the incidence of acute B19V infection, it is clinically important to continuously monitor their erythrocytes indices and screen their neonates for B19V infection and fetal complications.

Viral metagenomics in blood donations with post-donation illness reports from Brazil

BACKGROUND

Post-donation illness can be described as appearance of clinical symptoms in blood donors after donation. The consequent call back of the donor to report these symptoms to the blood collection institution is considered a post-donation illness report (PDIR). The most suitable way to examine whether PDIR is related to infection is to apply next-generation sequencing (NGS) and viral metagenomics. Investigation into a PDIR can reveal its importance for transfusion safety and help elaborate strategies for donor education in order to prevent the transfusion transmission of infections which are not routinely tested by the blood collection services.

MATERIALS AND METHODS

We applied NGS and viral metagenomics on blood donations which were deferred due to a PDIR. Thirty-three PDIR donations obtained in the Blood Center of Ribeirão Preto, Southeast Brazil, were evaluated. Sequencing was performed using Illumina NextSeq 550 (Illumina Inc, San Diego, CA, USA) equipment and the reads obtained for each sample were analysed by specific bioinformatic pipeline for the classification and discovery of emerging viruses. The identified viral agents by metagenomics were directly confirmed by molecular methods.

RESULTS

In all PDIR donations, we found abundant reads of commensal viruses belonging to the Anelloviridae family as well as human pegivirus-1. However, we were also able to identify blood donations positive for clinically important viruses like dengue serotype-2 (DENV-2) of the Asian-American genotype and parvovirus B19 (B19V). Both viruses were also confirmed by real-time polymerase chain reaction, detecting DENV-2 RNA in a significant number of cases (7 samples, 21.2%), compared to B19V which was confirmed in 1 case (3.0%).

DISCUSSION

Our study applies for the first time viral metagenomics to evaluate the significance of PDIRs. We confirm the crucial importance of the donor providing a timely PDIR for the prevention of transfusion transmission of viral infections which are not routinely tested in the blood banks worldwide.

Beyond Cytomegalovirus and Epstein-Barr Virus: a Review of Viruses Composing the Blood Virome of Solid Organ Transplant and Hematopoietic Stem Cell Transplant Recipients

Viral primary infections and reactivations are common complications in patients after solid organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT) and are associated with high morbidity and mortality. Among these patients, viral infections are frequently associated with viremia. Beyond the usual well-known viruses that are part of the routine clinical management of transplant recipients, numerous other viral signatures or genomes can be identified in the blood of these patients. The identification of novel viral species and variants by metagenomic next-generation sequencing has opened up a new field of investigation and new paradigms. Thus, there is a need to thoroughly describe the state of knowledge in this field with a review of all viral infections that should be scrutinized in high-risk populations. Here, we review the eukaryotic DNA and RNA viruses identified in blood, plasma, or serum samples of pediatric and adult SOT/HSCT recipients and the prevalence of their detection, with a particular focus on recently identified viruses and those for which their potential association with disease remains to be investigated, such as members of the Polyomaviridae, Anelloviridae, Flaviviridae, and Astroviridae families. Current knowledge of the clinical significance of these viral infections with associated viremia among transplant recipients is also discussed. To ensure a comprehensive description in these two populations, individuals described as healthy (mostly blood donors) are considered for comparative purposes. The list of viruses that should be on the clinicians' radar is certainly incomplete and will expand, but the challenge is to identify those of possible clinical significance.

Human parvovirus B19 frequency among blood donors after an epidemic outbreak: relevance of the epidemiological scenario for transfusion medicine

A retrospective, cross-sectional study was conducted to determine the frequency of human parvovirus B19 (B19V) infected individuals, viral loads and immunity among blood donors from Argentina, in a post-epidemic outbreak period. B19V DNA and specific IgG were tested in minimum study samples of donors attending a blood bank at Córdoba, Argentina, in 2014. Anti-B19V IgM and viral loads were determined in B19V-positive plasma samples. Seven of 731 samples (0.96%) resulted positive, corresponding to individuals aged 32-53 years, four of them repeat donnors and three first-time donors. Viral loads were <10³ IU/mL. None had IgM and 6/7 had IgG, one of them at a high level (in the range of 100-200 IU/ml, and the remaining 5 at low to medium level, 5-50 IU/ml). Thus one case was classified as acute infection (DNA+/IgM-/IgG-) and six as potentially persistent infections (DNA+/IgM-/IgG+). No coinfections with other pathogens of mandatory control in the pre-transfusion screening were detected. Prevalence of IgG was 77.9% (279/358). This study provides the first data of B19V prevalence in blood donors in Argentina, demonstrating high rates of acute and persistent B19V infections and high prevalence of anti-B19V IgG in a post-epidemic period. Further research is needed to elucidate mechanisms/factors for B19V persistence as well as follow-up of recipients in the context of haemo-surveillance programs, contributing to the knowledge of B19V and blood transfusion safety.

An assessment of the risk, cost-effectiveness, and perceived benefits of anti-parvovirus B19 tested blood products

BACKGROUND

Parvovirus B19 (B19V) can cause severe anemia, hydrops foetalis, and even death in vulnerable patients. To prevent transfusion-transmitted B19V infection of at-risk patients, B19V antibody screening of blood donors was implemented. The cost-effectiveness of this intervention is unclear, as the likelihood of transmission through blood and subsequent complications for recipients are unknown. This study estimates the cost-effectiveness of anti-B19V donor screening in the Netherlands.

STUDY DESIGN AND METHODS

The estimates needed for the cost-effectiveness model were: the occurrence of B19V in Dutch blood donors, the number of anti-B19V tested products required by hospitals, the likelihood of morbidity and mortality given B19V infection, treatment costs, and screening costs. These estimates were obtained from literature and observational data. When data were unavailable, structured expert judgment elicitation and statistical modeling were applied.

RESULTS

The costs of preventing one transfusion transmitted B19V infection are estimated at €68,942 (€42,045 - €102,080). On average, 1.25 cases of morbidity and 0.12 cases of mortality are prevented annually. Although the perceived risk of transfusion transmitted B19V infection was low, half of the treating physicians favored anti-B19V screening.

CONCLUSION

The estimated mortality and morbidity caused by B19V infection was low in the risk groups. The cost-effectiveness ratio is similar to other blood safety screening measures. No guidance exists to evaluate the acceptability of this ratio. The explicit overview of costs and effects may further guide the discussion of the desirability of B19V safe blood products.

Human parvovirus B19 in solid organ transplantation: Guidelines from the American society of transplantation infectious diseases community of practice

Clinical manifestations of human parvovirus B19 infection can vary widely and may be atypical in solid organ transplant (SOT) recipients. However, disease is apparent when there is destruction of erythrocyte progenitor cells leading to severe acute or chronic anemia with lack of an appropriate reticulocyte response in the setting of active parvovirus B19 infection. Serology may not reliably establish the diagnosis. High-level viremia is more likely to be associated with symptomatic disease. Conversely, ongoing DNAemia after infection may not be clinically significant, if detected at low levels. Despite lack of robust data, intravenous immunoglobulin (IVIG) is frequently used for the treatment of SOT recipients with symptomatic parvovirus B19 infection. Although the optimal dosage and duration of IVIG is not known, most patients receive a total of 2 g/kg over a period of 2-5 days. A daily dose of 1 g/kg or more seems to be associated with higher incidence of toxicity. Application of standard and droplet isolation precautions remains the cornerstone for preventing human parvovirus B19 transmission. Additional research is needed to assess the efficacy of current and novel therapies and to develop a safe and effective parvovirus B19 vaccine.

Low human parvovirus B19 (B19V) DNA prevalence in blood donors from Central-West Brazil

Parvovirus B19 (B19V) transmission may occur through blood transfusion as a result of asymptomatic viral persistence in blood donors. Our study evaluated the prevalence and viral load of B19V in blood donors from Brasilia, Federal District, Central-West Brazil. B19V DNA detection and quantification were performed in 477 blood donors. The positive samples were also tested for anti-B19V IgG and haemoderivative recipients were investigated for adverse effects following transfusion. B19V DNA prevalence was 0.21  % (n=1/477). The positive B19V DNA sample was also anti-B19 IgG-positive (probably persistent infection). The viral load was low and no adverse effects following blood transfusion were registered in the recipients. This study demonstrated that the B19V DNA prevalence in blood donors from Central-West Brazil is low. Nevertheless, the mere presence of B19V DNA in blood donors strengthens the need for viral molecular screening, especially in haemoderivatives that that will go to susceptible recipients.

Parvovirus B19 in South African blood donors

BACKGROUND

Parvovirus B19 (PVB19) is transmitted via transfusion of blood and blood products. PVB19 is resistant to viral inactivation methods, which poses a threat to blood safety. We investigated the prevalence of PVB19 antibodies and DNA in healthy blood donors from the South African National Blood Bank Service to evaluate the necessity of PVB19 DNA testing.

STUDY DESIGN AND METHOD

A retrospective analysis of 1500 residual plasma specimens from healthy blood donors from the SANBS repository were screened in mini-pools of 20 for PVB19 DNA using a quantitative polymerase chain reaction (PCR). Positive pools were resolved by individual viral load testing and screened for PVB19 immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies to correlate viral loads with serological status. PVB19 IgG prevalence was determined by testing 90 randomly selected specimens from the 1500 plasma specimens.

RESULTS

The prevalence of PVB19 IgG, IgM and IgG, and DNA was 62.2%, 0.06%, and 0.9%, respectively. Fourteen of the 1500 blood donor specimens received, had detectable PVB19 viral loads. Nine of the fourteen donors with detectable viral loads were PVB19 IgG seropositive. The PVB19 viral loads ranged from 1.81 to 5.32 log IU/mL. Four of the fourteen viraemic donors had a viraemia >10 ⁴ IU/mL.

CONCLUSION

We have demonstrated a low prevalence of PVB19 DNA in SANBS blood donors. The predominance of low-level viraemia and the presence of PVB19 antibodies, suggests that the risk of transfusion transmission of PVB19 among SANBS donors may be relatively low.

Modeling the parvovirus B19 blood safety risk in Australia

BACKGROUND

Three probable cases of transfusion-transmitted (TT) parvovirus B19 (B19V) occurred in Australia between 2014 and 2017. This study aimed to determine the B19V DNA prevalence among blood donors, to model the risk to recipients of fresh components, and to assess risk management options.

STUDY DESIGN AND METHODS

Plasma samples from 4232 donors were tested for B19V DNA by polymerase chain reaction. Reactive samples were confirmed and viral load determined. A transmission-risk model was used to estimate recipient risk, and the risk from community exposure was estimated using seroprevalence data.

RESULTS

Two samples (0.0473%, 95% confidence interval [CI] 0.0130-0.172) confirmed positive for B19V DNA had a potentially infectious viral load of 10⁵ IU/mL or higher. The estimated risk of a TT-B19V-associated significant complication was low overall at approximately 1 in 300,000 (95% CI, 1 in 82,000 to 1 in 1 million) fresh components transfused, with 3.1 (95% CI, 0.85-11.3) complications modeled per year. Among vulnerable recipient groups, the risk was higher than 1 in 15,000 patients, but the risk from community exposure far exceeded the transfusion risk for all patient and age groups.

CONCLUSION

In the context of the small contribution of transfusion to the burden of B19V disease, the significant costs that would be incurred by any strategy to reduce the risk, and given the significant uncertainties and likely overestimation of the risk, we conclude TT-B19V is a tolerable risk to blood safety, despite being high for some vulnerable recipient groups.

Seroprevalence of antibodies to primate erythroparvovirus 1 (B19V) in Australia

Backgroud

Primate erythroparvovirus 1 (B19V) is a globally ubiquitous DNA virus. Infection results in a variety of clinical presentations including erythema infectiosum in children and arthralgia in adults. There is limited understanding of the seroprevalence of B19V antibodies in the Australian population and therefore of population-wide immunity. This study aimed to investigate the seroprevalence of B19V antibodies in an Australian blood donor cohort, along with a cohort from a paediatric population.

Methods

Age/sex/geographical location stratified plasma samples (n = 2221) were collected from Australian blood donors. Samples were also sourced from paediatric patients (n = 223) in Queensland. All samples were screened for B19V IgG using an indirect- enzyme-linked immunosorbent assay.

Results

Overall, 57.90% (95% CI: 55.94%–59.85%) of samples tested positive for B19V IgG, with the national age-standardized seroprevalence of B19V exposure in Australians aged 0 to 79 years estimated to be 54.41%. Increasing age (p < 0.001) and state of residence (p < 0.001) were independently associated with B19V exposure in blood donors, with the highest rates in donors from Tasmania (71.88%, 95% CI: 66.95%–76.80%) and donors aged 65–80 years (78.41%, 95% CI: 74.11%–82.71%). A seroprevalence of 52.04% (95% CI: 47.92%–56.15%) was reported in women of child-bearing age (16 to 44 years). Sex was not associated with exposure in blood donors (p = 0.547) or in children (p = 0.261) screened in this study.

Conclusions

This study highlights a clear association between B19V exposure and increasing age, with over half of the Australian population likely to be immune to this virus. Differences in seroprevalence were also observed in donors residing in different states, with a higher prevalence reported in those from the southern states. The finding is consistent with previous studies, with higher rates observed in countries with a higher latitude. This study provides much needed insight into the prevalence of B19V exposure in the Australian population, which has implications for public health as well as transfusion and transplantation safety in Australia.