Infected Blood Donors Research Articles

Transfusional malaria in the neonatal period in Lagos, South-West Nigeria.

Background and objectivesSick neonates in malaria endemic areas are frequently transfused with donor blood unscreened for malaria parasite. Consequently, they are at risk of transfusional malaria which can lead to increased neonatal mortality. The study aimed to determine the burden of transfusional malaria in neonates to help in policy formulation on prevention of transfusional malaria.Materials and methodsOne hundred and sixty four neonates admitted into the neonatal unit of a tertiary hospital over a 10 month period who were scheduled for blood transfusion were screened for malaria parasites pre-transfusion, at three and 14 days post transfusion using Giemsa stained thick and thin films. Donor blood was screened for malaria parasites at the point of transfusion. Neonates who developed malaria parasitaemia post transfusion were followed up for signs of malaria.ResultsAll recruited neonates tested negative to malaria parasite pre- transfusion. One hundred and twenty (73.2%) were term neonates with 94(57.3%) aged 1-7days. Four (2.4%) neonates developed malaria parasitaemia three days post transfusion and all four developed fever that resolved on treatment for malaria. Three (1.8%) of 164 donor blood samples had malaria parasitaemia and all three (100%) neonates who were transfused with the infected donor blood developed malaria parasitaemia post transfusion. However, one neonate who developed malaria parasitaemia post transfusion was transfused with non-infected donor blood.ConclusionsThe prevalence of transfusional malaria in this study is low (2.4%). However, 100% of neonates who received malaria infected donor blood developed transfusional malaria. We therefore recommend routine screening of donor pre-transfusion, testing of neonates who develop fever post transfusion and treatment of those who test positive to malaria.

Epidemiological features of chronic hepatitis C infection caused by remunerated blood donors: A nearly 27-year period survey.

AIMTo understand the prevalence of hepatitis C virus (HCV) infection in blood donors over a nearly 27-year interval and to explore the factors that affect the outcome of HCV infection.METHODSA retrospective and cross-sectional study was conducted. The participants, mostly plasma donors, were selected from three administrative villages in the Jiangsu province in Eastern China. A questionnaire was administered among the villagers who had a history of blood donation from the late 1980s to the early 1990s. All participants underwent physical examination, liver B-ultrasonography, and liver stiffness measurement. In addition, 10 mL of blood was collected from each participant to measure simple liver function parameters (albumin, alanine aminotransferase, aspirate aminotransferase), blood factors (platelet), and for hepatitis B surface antigen, antiHCV, and antihuman immunodeficiency virus detection. HCV RNA detection, HCV genotyping, and other tests were carried out in antiHCV-positive patients.RESULTSAfter a median of 27 years (25-31 years) from the last blood donation to the time of survey, a total of 1694 participants were investigated, and the antiHCV-positive individuals were categorized into three groups: blood donors (n = 12, 3.3%), plasma donors (n = 534, 68.5%), and mixed donors (n = 324, 58.8%). A total of 592 (68.05%) patients had detectable HCV RNA, and 91.9% had genotype 1b. A total of 161 (27.2%, 161/592) patients with chronic HCV were considered to have cirrhosis with a liver stiffness measurement level higher than 12 kPa. Multiple logistic (binary) regression analysis results showed that platelet and IgG levels were associated with cirrhosis.CONCLUSIONThe nearly 27-year interval investigation revealed that chronic hepatitis C infection is a very serious public health problem in Eastern China. Plasma donation and subsequent return of blood cells to the donor are the main causes of hepatitis C infection. The main HCV genotype is 1b. Nearly 28% of cases progressed to cirrhosis. Age, especially over 60 years, and regular drinking habits were risk factors associated with cirrhosis.

The Brazilian experience of nucleic acid testing to detect human immunodeficiency virus, hepatitisC virus, and hepatitisB virus infections in blood donors.

The history of the development and implementation of the Brazilian nucleic acid testing (NAT) platform to detect and discriminate among human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV) infections in blood donors is described here. The results for the sensitivity, reproducibility, and NAT yield of the platform since program implementation are provided. The Brazilian NAT HIV, HCV, and HBV kit was developed and evaluated with regard to analytical sensitivity, specificity, intralot and interlot reproducibility, interfering substances, and genotype and diagnostic sensitivity. Additionally, a sample of identified NAT-yield cases was characterized with regard to viral load. The 95% limits of detection for HIV, HCV, and HBV were 68.02, 102.35, and 9.08 IU/mL, respectively. All replicates were detected with reproducibility assays between the acceptable values. A total of 13,610,536 blood donors was screened from 2010 to 2016, and 63 HIV-yield cases and 28 HCV-yield cases were detected. Among 5,795,424 blood donors screened for HBV from 2014 to 2016, 42 yield cases were found. The Brazilian NAT HIV, HCV, and HBV kit is an automated NAT system suitable for routine blood donor screening in a completely traceable process. The analytical sensitivity as well as the diagnostic sensitivity fulfilled all requirements set by the health ministry for blood donor screening. A significant number of transmission cases were prevented by the implementation of this important program.

Seroprevalence of Toxoplasma gondii infection in blood donors in mainland China: a systematic review and meta-analysis.

Toxoplasma gondii transmitted from blood donors to receiving patients has become a concern as numerous articles about the epidemiology of T. gondii infection in blood donors from different provinces have been published in China. This study aimed to evaluate the seroprevalence of T. gondii infection in Chinese blood donors using a meta-analysis. A total of 40 eligible studies, published from 1986 to 2017 and covering 18 provinces and municipalities were included. Among a total of 49,784 Chinese blood donors, the overall IgG seroprevalence of T. gondii infection was 6.26% (95% CI: 4.62%–8.13%). The highest prevalence was in the Northeast of China and the lowest in Central China. The infection rate increased slowly over the years, but not significantly. A statistically significant correlation was found between the seroprevalence of T. gondii infection and the detection method and educational level (p < 0.01). There was no relationship between age, gender, occupation and blood type and seroprevalence of T. gondii (p > 0.05). The prevalence of antibodies to T. gondii in Chinese blood donors was lower than in other countries, but the risk of transfusion-transmitted toxoplasmosis still exits. More concise methods are still needed to evaluate the possibility of transfusion-transmitted toxoplasmosis from blood donors.

Evaluation of efficacy of serological methods for detection of HCV infection in blood donors: A single centre experience.

Background and Objective:Blood transfusion is an essential and life-saving medical intervention. Despite multiple preventive measures transfusion-transmitted hepatitis C virus (HCV) infection continues to be a major healthcare issue in Pakistan. This study was conducted at National Institute of Blood Diseases & Bone Marrow Transplantation to evaluate the frequency of active HCV infection with or without co-infection in blood donors and also to determine comparative efficacy of Multisure HCV antibody assay (MHAA); a new serological device.Methods:A total of 14652 blood donors visiting National Institute of Blood Diseases & Bone Marrow Transplantation (NIBD) Blood Bank from January 2013 to July 2014 were enrolled and screened for a range of blood borne infections such as HBV, HCV, HIV, malaria and syphilis. The HCV was screened simultaneously by Abbot Architect anti-HCV assay (CLIA) and MHAA. The active HCV infection was confirmed by nucleic acid testing (NAT) in reactive donors. Later; for determination of comparative efficacy of MHAA; all NAT positive samples were further tested using Monolisa™, HCV blot 3.0, Anti-HCV plus V2 and Anti-HCV-MPBIO-EIA.Results:The HCV reactive sera were observed in 1.563% (226) donors. The NAT confirmed active HCV infection in 138 donors. Overall 27.84% of HCV positive donors exhibited co-infection either with HBV (2.57%), syphilis (22.78%). Triple infection was not observed in any donor. The efficacy of MHAA is comparable to all the serological tests with a sensitivity of about 96.89%.Conclusion:Active HCV infection was present in 0.94% donors. With a sensitivity of 96.89% (95% CI: 95.66-98.12) the multi-parametric device MHAA can effectively detect HCV infection in donors. Thus, it can be used in limited health care settings for HCV screening.

Next-Generation Sequencing of Hepatitis C Virus (HCV) Mixed-Genotype Infections in Anti-HCV-Negative Blood Donors.

The infection with more than one hepatitis C virus (HCV) genotype especially in subjects with a high risk of multiple HCV exposures has been demonstrated. The role of HCV mixed-genotype infection in viral persistence and treatment effect is not fully understood. The prevalence of such infection varies greatly depending on the technique used for genotype determination and studied population. Next-generation sequencing (NGS) which is suitable for extensive analysis of complex viral populations is a method of choice for studying mixed infections. The aim of the present study was to determine the prevalence of mixed-genotype HCV infections in the Polish seronegative, HCV-RNA-positive blood donors (n=76). Two-step PCR was used for amplification of 5'-UTR of HCV. Using pyrosequencing altogether, 381,063 reads were obtained. The raw reads were trimmed and subjected to similarity analysis against the entire unfiltered NCBI nt database. Results obtained from NGS were compared with the standard genotyping. One (1.3%) mixed-genotype [3a, 2989 reads (94.8%); 1b, 164 reads (5.2%)] infection was found in a sample diagnosed as genotype 3a only by routine testing. Two samples were identified with different genotypes, compared to routine testing. In conclusion, NGS is a sensitive method for HCV genotyping. The prevalence of mixed-genotype HCV infections in blood donors is low.

Which Infectious Blood Donors Could Be Identified by the Donor History Questionnaire - Comparison of Blood Donors Infected with HIV or HCV with Notified Cases from General Population in Germany

Background: Potential risks for transfusion-transmissible infections are identified by donor history questionnaires (DHQs), and donors with higher risks are deferred from donation. We assessed to which extent the currently used DHQs support the identification of infections among blood donors. Methods: Between 2006 and 2013, we analyzed data from notified HIV and HCV cases in the general population and positive blood donors in Germany. Logistic regressions were used to identify relevant infection risks. We estimated the possible effect of improved capture of risk factors for donor selection by calculation of population attributable fractions (PAF). Results: Risky sexual contacts - MSM as well as heterosexual contacts - were the most prominent infection risks among HIV-infected donors. Whereas MSM contacts were significantly less reported by donors than by cases from the general population, 58% of donors disclosed heterosexual risks compared to 26% of notified cases. The complete identification of heterosexual risk contacts might prevent acceptance of 53% of HIV-infected donors. HCV-infected donors were more likely to report heterosexual exposure, imprisonment, and piercing/tattoo than notified HCV cases. Improved recording of piercing/tattoo could prevent acceptance of 16% of HCV-infected donors. Conclusion: Donor selection should be improved with special attention to the identification of (hetero)sexual risk factors, invasive procedures (piercing/tattoo and imprisonment) applying well-designed DHQs, effective donor education, and confidential environment in all steps of the selection process.

Asymptomatic infections in blood donors harbouring Plasmodium: an invisible risk detected by molecular and serological tools.

Transfusion-transmitted malaria due to asymptomatic Plasmodium infections is a challenge for blood banks. There is a lack of data on the prevalence of asymptomatic infected blood donors and the incidence of transfusion-transmitted malaria in low endemicity areas worldwide. We estimated the frequency of blood donors harbouring Plasmodium in an area in which asymptomatic infections have been reported. To estimate the frequency of blood donors harbouring Plasmodium we used microscopy and molecular tools. Serological tests were applied to measure the exposure of candidates to Plasmodium antigens. Venous blood was collected from 91 candidates attending the "Pró-Sangue" Blood Centre Foundation in São Paulo, who lived in the municipality of Juquitiba, São Paulo, Brazil, where sporadic autochthonous cases of malaria have been described. Blood samples were used for parasitological, molecular and serological studies. Among the 91 samples examined, rare Plasmodium forms were observed in two donors. Genus real-time polymerase chain reaction analysis demonstrated Plasmodium amplification in three candidates and species-specific nested polymerase chain reaction identified P. malariae in two. ELISA-IgG was reactive in 42.9% of samples for P. vivax (Pv-MSP119) and in 6.6% for P. falciparum (Pf-Zw). ELISA-IgM was reactive in 2.2% of samples for P. vivax and in 4.4% for P. falciparum. An indirect immunofluorescence assay was reactive for P. malariae in 15.4% of cases. Reservoirs of Plasmodium represent a challenge for blood banks, since studies have shown that high levels of submicroscopic infections can occur in low transmission areas. The risk of transfusion-transmitted malaria presented here points to the need to conduct molecular investigations of candidate donors with any positive malarial antibody test.

High prevalence of HIV-1 transmitted drug-resistance mutations from proviral DNA massively parallel sequencing data of therapy-naïve chronically infected Brazilian blood donors.

BackgroundAn improved understanding of the prevalence of low-abundance transmitted drug-resistance mutations (TDRM) in therapy-naïve HIV-1–infected patients may help determine which patients are the best candidates for therapy. In this study, we aimed to obtain a comprehensive picture of the evolving HIV-1 TDRM across the massive parallel sequences (MPS) of the viral entire proviral genome in a well-characterized Brazilian blood donor naïve to antiretroviral drugs.Materials and methodsThe MPS data from 128 samples used in the analysis were sourced from Brazilian blood donors and were previously classified by less-sensitive (LS) or “detuned” enzyme immunoassay as non-recent or longstanding HIV-1 infections. The Stanford HIV Resistance Database (HIVDBv 6.2) and IAS-USA mutation lists were used to interpret the pattern of drug resistance. The minority variants with TDRM were identified using a threshold of ≥ 1.0% and ≤ 20% of the reads sequenced. The rate of TDRM in the MPS data of the proviral genome were compared with the corresponding published consensus sequences of their plasma viruses.ResultsNo TDRM were detected in the integrase or envelope regions. The overall prevalence of TDRM in the protease (PR) and reverse transcriptase (RT) regions of the HIV-1 pol gene was 44.5% (57/128), including any mutations to the nucleoside analogue reverse transcriptase inhibitors (NRTI) and non-nucleoside analogue reverse transcriptase inhibitors (NNRTI). Of the 57 subjects, 43 (75.4%) harbored a minority variant containing at least one clinically relevant TDRM. Among the 43 subjects, 33 (76.7%) had detectable minority resistant variants to NRTIs, 6 (13.9%) to NNRTIs, and 16 (37.2%) to PR inhibitors. The comparison of viral sequences in both sources, plasma and cells, would have detected 48 DNA provirus disclosed TDRM by MPS previously missed by plasma bulk analysis.ConclusionOur findings revealed a high prevalence of TDRM found in this group, as the use of MPS drastically increased the detection of these mutations. Sequencing proviral DNA provided additional information about TDRM, which may impact treatment decisions. The overall results emphasize the importance of continuous monitoring.

Seroprevalence of Strongyloides stercoralis infection among HTLV-I infected blood donors in Barcelona, Spain: A cross-sectional study

Strongyloides stercoralis infection in patients with HTLV-I infection may lead to severe clinical manifestations. The aim of the present study is to determine the seroprevalence of S. stercoralis infection among blood donors who tested positive for HTLV-I infection. A cross-sectional study was performed at the Vall d’Hebron University Hospital (Barcelona, Spain) in 2016. Serum samples from HTLV-I positive patients diagnosed from 2008 to 2015 were retrieved from the Blood Bank, and S. stercoralis serology was performed. Thirty six serum samples from HTLV-I positive patients were retrieved from the Blood Bank. The blood samples came from 36 blood donors, and most of them were born in Latin America (75%), being Peru the most frequent country (11 participants). S. stercoralis serology was positive in one patient, corresponding to a prevalence of 2.8% (3.4% if we exclude donors coming from European countries, where the risk of S. stercoralis infection is highly unlikely).

First outbreak of Zika virus in the continental United States: a modelling analysis.

Since 2015, Zika virus (ZIKV) has spread throughout Latin and Central America. This emerging infectious disease has been causing considerable public health concern because of severe neurological complications, especially in newborns after congenital infections. In July 2016, the first outbreak in the continental United States was identified in the Wynwood neighbourhood of Miami-Dade County, Florida. In this work, we investigated transmission dynamics using a mathematical model calibrated to observed data on mosquito abundance and symptomatic human infections. We found that, although ZIKV transmission was detected in July 2016, the first importation may have occurred between March and mid-April. The estimated highest value for R0 was 2.73 (95% confidence interval (CI): 1.65–4.17); the attack rate was 14% (95% CI: 5.6–27.4%), with 15 (95% CI: 6–29) pregnant women involved and a 12% probability of infected blood donations. Vector control avoided 60% of potential infections. According to our results, it is likely that further ZIKV outbreaks identified in other areas of Miami-Dade County were seeded by commuters to Wynwood rather than by additional importation from international travellers. Our study can help prepare future outbreak-related interventions in European areas where competent mosquitoes for ZIKV transmission are already established.

WITHDRAWN: Comparison of electrochemiluminescence and enzyme-linked immunosorbent assay methods used in the diagnosis of human immunodeficiency virus, hepatitis B virus and hepatitis C virus infections in blood donors in Libreville (Gabon)

Abstract Safe blood transfusion remains a health-related challenge in Sub-Saharan Africa. High prevalence of blood-borne infectious agents, lack of financial resources, well trained personnel are some of the root causes to not efficiently reduce the rate of post-transfusion transmission of human immunodeficiency virus (HIV), hepatitis B and C viruses (HBV and HCV). Objective This report sought to assess the performances of Cobas 6000 e601 and EVOLIS BIORAD in the detection of HIV, HBV and HCV in blood donors in Libreville (Gabon). Methods A cross-sectional investigation was conducted in July 2017 in a group of 2,000 blood donors recruited at the National Blood transfusion Center (NBTC), Libreville Gabon. Of them, 363 donors were selected to compare the performances of COBAS 6000 e601 (electro-chemiluminescence) and EVOLIS BioRad in detecting HIV, HBV and HCV using Cohen’s kappa coefficient. Results Both methods yielded similar results for the detection of HIV and HBsAg. Indeed, a very good agreement of 93.39% and an excellent agreement of 98.90% were obtained for the detection of HIV and HbsAg, respectively, with kappa values of 0.80 and 0.98. The observed agreement of 91.86% was found for the detection of HC, which gave a fair agreement between the two methods with kappa=0.33. Conclusion The two evaluated methods of detection showed a similar performance in the detection of HIV, HBV. However, given the high rate of intra and inter-genotypes recombination known for HIV and HBV more robust technique of detection such as polymerase chain reaction should be used to prevent post-transfusion contaminations.

HIV-Sero-prevalence trend among blood donors in North East Ethiopia.

Although blood transfusion is one of the known therapeutic interventions that cuts across a number of clinical disciplines. It is necessary to test all intending blood donors for HIV infection before donation. The aim of this study was to determine the prevalence of HIV among blood donors at Dessie Blood Bank, Northeast Ethiopia. A retrospective study was conducted in Dessie Blood Bank through the year 2008-2012. Sera from blood donors were tested for the detection of Anti HIV by using 4th generation ELISA. Data were abstracted from records and analyzed using Microsoft Excel sheet. From the total of 9384 screened blood samples collected, the prevalence of HIV in blood donors in the blood bank was 5.1% in the five consecutive years but the trend of HIV infection has decreased from 2008(5.2%) to 2012 (2.3%). The age groups 15-24 and 35-44 were the highest prevalence and the age group 45-54 was the lowest prevalence of HIV infection. The prevalence of HIV among female (7.9%) was higher than in male donors (4.4%). The trend of HIV infection was decreasing for both male and female blood donors. The prevalence of HIV infections among blood donors is still high in this study setting, and needs constant monitoring to evaluate prevention and control strategies to reduce the burden of transfusion-transmissible HIV infections.

Comparative evaluation of a rapid diagnostic test, an antibody ELISA, and a pLDH ELISA in detecting asymptomatic malaria parasitaemia in blood donors in Buea, Cameroon

BackgroundIn malaria endemic areas, infected blood donors serve as a source of infection to blood recipients, which may adversely affect their prognosis. This necessitates the proper screening of blood to be used for transfusion in these areas. The purpose of this study was to determine the prevalence of malaria parasitaemia in blood donors in Buea, Cameroon, and to evaluate the performance of a rapid diagnostic test (RDT), a malaria antibody enzyme-linked immunosorbent assay (ELISA), and a Plasmodium lactate dehydrogenase (pLDH) ELISA in the detection of asymptomatic malaria parasitaemia in the target population.MethodsIn a prospective study conducted between September 2015 and June 2016, 1 240 potential blood donors were enrolled. The donors were screened for malaria parasites using Giemsa microscopy (GM) and a RDT. A sub-sample of 184 samples, comprising 88 positive and 96 negative samples, were selected for the evaluation of the pLDH ELISA and the antibody ELISA. The chi-square test and correlation analysis were performed as part of the statistical analyses. The statistical significance cut-off was set at P < 0.05.ResultsThe prevalence of malaria parasitaemia in this study was found to be 8.1% (95% CI: 6.6 – 9.7). The prevalence was not observed to be dependent on the age or sex of the participants. The RDT had a sensitivity (88.0%), specificity (99.1%), and negative predictive value (99.0%) higher than the ELISAs. The performance of the pLDH ELISA, which demonstrated the highest positive predictive value (91.6%), was generally comparable to the RDT. The sensitivity was lowest with the antibody ELISA (69.9%), which also demonstrated the highest false positive and false negative rates. The detection threshold for the pLDH (three parasites/μl) was lower compared to the RDT (50 – 60 parasites/μl). Non-significant positive correlations were observed between the parasite density and the pLDH titers and malaria antibody titers.ConclusionsOverall, the RDT and the pLDH ELISA demonstrated a perfectly correlated agreement with GM, meanwhile the antibody ELISA demonstrated a substantially correlated agreement with GM. The pLDH is therefore recommended for mass screening of blood (to detect malaria parasitaemia) for transfusions in the study area. However, where this is not feasible, an RDT will suffice.

Epidemiological trends of HIV-1 infection in blood donors from Catalonia, Spain (2005-2014).

Human immunodeficiency virus 1 (HIV-1) subtype B is predominant in Spain. However, the recent arrival of immigrant populations has increased the prevalence of non-B subtypes and circulating recombinant forms. The objective of this study was to determine the prevalence of HIV-1 subtypes and transmitted drug-resistance mutations in blood donors from the Catalonian region (northeastern Spain). HIV-1-positive blood donors identified in Catalonia from 2005 to 2014 were included. Demographic variables and risk factors for HIV-1 acquisition were recorded. HIV-1 subtyping was carried out by HIV-1 DNA polymerase region sequencing, and phylogenetic analyses were performed using the neighbor-joining method. During the study period, 2.8 million blood donations were screened, and 214 HIV-1-positive donors were identified, yielding an overall prevalence of 7.7 per 100,000 donations (89% men; mean age, 34 ± 10 years). Most HIV-1-positive donors were native to Spain (81%), and 61% were regular blood donors. When risk factors were known, 62% reportedly were men who had sex with men. HIV-1 subtyping was possible in 176 HIV-1-positive individuals: 143 (81%) had HIV-1 subtype B, and 33 (19%) had non-B subtypes. Most HIV-1 non-B subtypes were circulating recombinant forms (n = 20; 61%). Factors associated with HIV-1 subtype B were male sex (p = 0.007) and men who had sex with men (p < 0.001). The overall prevalence of transmitted drug-resistance mutations was 14%. Non-B subtypes, circulating recombinant forms, and transmitted drug-resistance mutation sequences circulate among HIV-1-positive blood donors in Catalonia. Continuous local epidemiological surveillance is required to implement optimal prevention strategies for controlling transfusion-transmitted HIV and to improve health policies regarding HIV infection.

Hepatitis B genotypes and surface antigen mutants present in Pakistani blood donors.

BackgroundThe prevalence of chronic Hepatitis B Virus (HBV) infection is 2–4% in the Pakistani population, defining Pakistan as an intermediate prevalence country. In this study, hepatitis B surface antigen (HBsAg) reactive blood donations were screened using a combination of serological and molecular methods to identify immune escape HBV mutant strains and to determine the HBV genotypes and subtypes present in Pakistan.MethodsBlood donations were collected at the Armed Forces Institute of Transfusion (AFIT) located in northern Pakistan and the Hussaini Blood Bank (HBB) located in the south. From 2009 to 2013 a total of 706,575 donations were screened with 2.04% (14,409) HBsAg reactive. A total of 2055 HBsAg reactive specimens, were collected and screened using a monoclonal antibody based research assay to identify immune escape mutants followed by PCR amplification and DNA sequencing to identify the mutation present. DNA sequences obtained from 192 specimens, including mutant candidates and wild type strains, were analyzed for escape mutations, genotype, and HBsAg subtype.ResultsMutations were identified in approximately 14% of HBsAg reactive donations. Mutations at HBsAg amino acid positions 143–145 are the most common (46%) with the mutation serine 143 to leucine the most frequently occurring change (28%). While regional differences were observed, the most prevalent HBV strains are subgenotypes of D with subgenotype D1/subtype ayw2 accounting for the majority of infections; 90.2% at AFIT and 52.5% at HBB.ConclusionsThe high frequency of immune escape HBV mutants in HBV infected Pakistani blood donors highlights the need for more studies into the prevalence of escape mutants. Differences between vaccinated and unvaccinated populations, the correlation of escape mutant frequency with genotype, and impact of escape mutations in different genotype backgrounds on the performance of commercially available HBsAg assays represent avenues for further investigation.

Molecular detection of Zika virus in blood and RNA load determination during the French Polynesian outbreak.

Zika virus (ZIKV) viremia is reported as low and transient; however, these estimates rely on limited data. We report RNA loads in sera collected from symptomatic patients during the 2013‐2014 French Polynesian ZIKV outbreak. We performed molecular detection of ZIKV RNA in sera from 747 patients presenting with suspected acute phase ZIKV infection. Among patients with confirmed infection, we analyzed the duration of viremia, assessed viral RNA loads and recorded the main clinical symptoms. A total of 210/747 (28.1%) sera tested positive using a ZIKV‐specific RT‐PCR. Viral RNA loads in symptomatic patients that ranged from 5 to 3.7 × 106 copies/mL (mean 9.9 × 104 copies/mL) were not related to a particular clinical presentation, and were significantly lower than those previously obtained from asymptomatic ZIKV infected blood donors. The rate of detection of ZIKV RNA in sera from suspected cases of acute phase ZIKV infection was low. ZIKV RNA loads were lower in symptomatic patients compared to asymptomatic blood donors and were lower than RNA loads usually reported in dengue infections. As there is no abrupt onset of symptoms in ZIKV infections, we suggest that infected patients sought for medical attention when viremia was already decreasing or had resolved.

Toxoplasma Gondii Infection and Related Risk Factors Among Blood Donors in Northwest Iran

Background: Toxoplasmosis, a worldwide parasitic infection, is considered as a transfusion-transmitted disease. Objectives: Due to ignorance about Toxoplasma infection in blood donors monitoring and its important role in provision of safe blood and blood products and also poor information about the seroprevalence of T. gondii infection in blood donors, this study was conducted to assess anti-Toxoplasma gondii antibodies and associated risk factors among blood donors in northwest of Iran. Methods: In this cross- sectional study, 194 serum samples were collected from healthy blood donors who referred to Tabriz Blood transfusion organization (East Azerbaijan, Iran) during April and June 2014 and tested for anti-T. gondii IgM and IgG antibodies using chemiluminescence immunoassay. The questionnaire consisting of demographic and risk factors were filled for all the participants. Results: From 194 donors, 75 (38.66%) and 2 (1.03%) individuals were seropositive for anti-T. gondii IgG and IgM antibodies, respectively. In the present study, anti-T. gondii antibodies in first-time donors was significantly higher than those in regular blood donors (P < 0.05). A significant correlation was observed between T. gondii infection and age (P < 0.05); however, there were no relationship between Toxoplasma infection and other factors. Conclusions: Considering the medical importance of blood transfusion and high rate of anti- T. gondii antibodies in healthy blood donors, it seems that effective monitoring of infection is required to prevent transfusion- transmitted toxoplasmosis.

Description of 15 DNA-positive and antibody-negative "window-period" blood donations identified during prospective screening for Babesia microti.

Blood donation screening detecting only antibodies fails to identify donors in the earliest stage of infection, before a detectable immunologic response, that is, the "window period" (WP). We present data on WP donations identified during prospective screening for Babesia microti, a transfusion-transmissible parasite of increasing concern in the United States. Blood donations collected in Connecticut, Massachusetts, Minnesota, and Wisconsin were screened using polymerase chain reaction (PCR) and arrayed fluorescence immunoassay (AFIA) to detect B. microti DNA and antibodies, respectively. Parasite loads were estimated using quantitative PCR. Red blood cell (RBC) samples were inoculated into hamsters to assess infectivity. Donors screening reactive were indefinitely deferred, tested by supplemental methods, and followed to assess DNA and antibody clearance. Demographic data from WP donors (i.e., those screening PCR positive and AFIA negative) were compared to data from other positive donors. Of 220,479 donations screened from June 2012 to August 2016, a total of 700 were positive, of which 15 (2% of positive donations or 1 per 14,699 screened donations) were confirmed WP donations. The median estimated parasite load in WP donations was 350 parasites/mL, no different than AFIA-positive and PCR-positive donors. Parasite loads in RBC samples from WP units ranged from 14 to 11,022 parasites/mL; RBC samples from three of 10 (30%) WP donations infected hamsters. The mean age of WP donors was 48 years (range, 17-75 years); three (20%) were female. WP donor demographics did not differ significantly from demographics of other donors. We report one per 15,000 B. microti WP infections in blood donors in endemic areas, demonstrating the importance of nucleic acid testing to mitigate the risk of transfusion-transmitted babesiosis.

Frequency of Trypanosoma cruzi parasitemia among infected blood donors with a potential association between parasite lineage and transfusion transmission.

Trypanosoma cruzi is endemic to the Americas where it demonstrates multiple lineages over a vast geographic range (i.e., United States to Argentina). These lineages possess divergent geographic and biologic characteristics, including variations in disease manifestations. Herein, we report the frequency of parasitemia among seropositive US blood donors and the potential association between parasite lineage and transfusion transmission. Blood donors identified as T.cruzi seropositive during screening were enrolled in follow-up studies, including hemoculture testing and a risk factor questionnaire. Positive hemocultures were expanded to obtain sufficient parasites for molecular lineage determination and analysis. Country of birth, obtained from the questionnaire, was used to predict parasite lineage in the absence of demonstrable parasitemia for infected donors. Eighteen (6.8%) of 263 seropositive donors were hemoculture positive. Among the 17 hemocultures expanded for lineage determination, TcV was identified more frequently (n=12), compared to TcI (n=2), TcII (n=1), and TcVI (n=2). When presumptive parasite lineages were compared to hemoculture results, only two of 157 (1.3%) TcI versus 13 of 38 (34.2%) TcII/TcV/TcVI non-US donors were parasitemic; three of 44 (6.8%) US donors were TcV or TcVI. Based on lineage determination for donors with parasitemia; hemoculture positivity associated with presumptive parasite lineage; and implicated donors from US, Canadian, and Spanish transfusion cases, donors from Southern South America are significantly more likely to have parasitemia and transmit infection to blood recipients (TcII, TcV, or TcVI vs. TcI). Thus, parasite lineage may be associated with risk of transfusion-transmitted T.cruzi.