[Blood transfusion: control of infectious risks]

Gene expression profiling of p53 and c-myc in HTLV-1 positive blood donors in Congo

OBJECTIVES

The HTLV-1 infection persists for life, remaining as asymptomatic viral reservoirs in most patients, ensuring the chain of transmission, but around 4% develop adult T-cell leukemia/lymphoma (ATLL). HTLV-1 is an oncogenic retrovirus that transforms CD4+ T lymphocytes and deregulates the lymphoproliferative pathways that contribute to the development of ATLL. To achieve cell transformation, most oncogenic retroviruses use proto-oncogene capture transduction, with proviral integration disrupting the expression of tumor suppressors or proto-oncogenes.

THE AIM

We conducted this study on the prevalence of HTLV-1 infection in blood donors to expand the HTLV-1 database, assess the risk of transmission via blood products, as well as evaluate the risk of persistent infection or development of neoplastic diseases in HTLV-1 carriers.

MATERIALS AND METHODS

This is a cross-sectional study of blood donors of all categories. For this study, 265 blood donors were recruited at the Centre National de Transfusion Sanguine in Brazzaville. After testing for HTLV-1 antibodies by ELISA, proviral DNA was extracted from all ELISA-positive samples for detection by nested PCR, followed by RT qPCR using specific primers p53 and c-myc for gene expression.

RESULTS

20/265 were positive for anti-HTLV-1 antibody, 5 donors were positive for proviral DNA. The prevalence of HTLV-1 was 1.8%. All HTLV-1-positive donors were male (1.8%), with a positive correlation (p = 0.05); the 1.1% of positive donors were regular, with the majority aged between 31 and 45 years (1.5%), and concubine donors were the most frequent (1.1%). All samples showed normal expression of the p53 and c-myc genes.

CONCLUSION

The prevalence, though low, remains a serious problem. No abnormal p53 orc-mycgene expression was detected in HTLV-1-positive donors, which could mean that none of the T lymphocytes in these donors had been transformed by HTLV-1.

Seroreactivity to Chikungunya and West Nile Viruses in Rwandan Blood Donors

Introduction: Chikungunya virus (CHIKV) and West Nile virus (WNV) have previously been reported from several African countries, including those bordering Rwanda where they may have originated. However, there have been no serosurveillance reports from Rwanda regarding these two viral pathogens. In this article, we present the first study of immunoglobulin G (IgG) seroreactivity of CHIKV and WNV in Rwandan blood donor samples. Methods: Blood donors from Rwanda (n = 874) and Sweden (n = 199) were tested for IgG reactivity against CHIKV, using an in-house enzyme-linked immunosorbent assay with the E1 envelope protein fused with p62 as antigen, and against WNV using a commercial kit. Data on mosquito distribution were obtained from the 2012 assessment of yellow fever virus circulation in Rwanda. Results: Seroreactivity to CHIKV was high in Rwanda (63.0%), when compared with Swedish donors, where only 8.5% were IgG positive. However, a cross-reactivity to O'nyong'nyong virus in neutralization test was noted in Rwandan donors. No significant difference in WNV seroreactivity was found (10.4% for Rwandan and 14.1% for Swedish donors). The relatively high seroreactivity to WNV among Swedish donors could partly be explained by cross-reactivity with tick-borne encephalitis virus prevalent in Sweden. Donors from the Eastern Province of Rwanda had the highest IgG reactivity to the two investigated viruses (86.7% for CHIKV and 33.3% for WNV). Five genera of mosquitoes were found in Rwanda where Culex was the most common (82.5%). The vector of CHIKV, Aedes, accounted for 9.6% of mosquitoes and this species was most commonly found in the Eastern Province. Conclusions: Our results showed high seroreactivity to CHIKV in Rwandan donors. The highest IgG reactivity to CHIKV, and to WNV, was found in the Eastern Province, the area reporting the highest number of mosquito vectors for these two viruses. Infection control by eliminating mosquito-breeding sites in population-dense areas is recommended, especially in eastern Rwanda.

Transfusion-associated hazards: A revisit of their presentation

As a therapy or a support to other therapies, despite being largely beneficial to patients in general, transfusion it is not devoid of some risks. In a moderate number of cases, patients may manifest adverse reactions, otherwise referred to as transfusion-associated hazards (TAHs). The latest French 2016 haemovigilance report indicates that 93% of TAHs are minor (grade 1), 5.5% are moderate (grade 2) and 1.6% are severe (grade 3), with only five deaths (grade 4) being attributed to transfusion with relative certainty (imputability of level [or grade] 1 to 3). Health-care providers need to be well aware of the benefits and potential risks (to best evaluate and discuss the benefit-risk ratio), how to prevent TAHs, the overall costs and the availability of alternative therapeutic options. In high-income countries, most blood establishments (BEs) and hospital blood banks (HBBs) have developed tools for reporting and analysing at least severe transfusion reactions. With nearly two decades of haemovigilance, transfusion reaction databases should be quite informative, though there are four main caveats that prevent it from being fully efficient: (ai) reporting is mainly declarative and is thus barely exhaustive even in countries where it is mandatory by law; (aii) it is often difficult to differentiate between the different complications related to transfusion, diseases, comorbidities and other types of therapies in patients suffering from debilitating conditions; (aiii) there is a lack of consistency in the definitions used to describe and report some transfusion reactions, their severity and their likelihood of being related to transfusion; and (aiv) it is difficult to assess the imputability of a particular BC given to a patient who has previously received many BCs over a relatively short period of time. When compiling all available information published so far, it appears that TAHs can be analysed using different approaches: (bi) their pathophysiological nature; (bii) their severity; (biii) the onset scheme; (biv) a quality assessment (preventable or non-preventable); (bv) their impact on ongoing therapy. Moreover, TAHs can be reported either in a non-integrative or in an integrative way; in the latter case, presentation may also differ when issued by a blood establishment or a treating ward. At some point, a recapitulative document would be useful to gain a better understanding of TAHs in order to decrease their occurrence and severity and allow decision makers to determine action plans: this is what this review attempts to make. This review attempts to merge the different aspects, with a focus on the hospital side, i.e., how the most frequent TAHs can be avoided or mitigated.

[Transfusion-transmitted Infections: How Useful and Costly is Testing for new Infectious Disease Pathogens?]

Zusammenfassung. Bis Anfang der 1990er Jahre waren Blutprodukte nicht selten mit HIV oder HCV kontaminiert, was zu vielen transfusionsbedingten Infektionen führte. Seither wurde die Sicherheit von Blutprodukten in Bezug auf die Infektionsübertragung mit aufwendigen Massnahmen stark erhöht. Aktuell stehen sogenannte (re)emerging-Infektionserreger im Fokus, beispielsweise West Nile-, Zika- und Hepatitis-E-Viren. Ob und wie sich neue Massnahmen, die eine Übertragung dieser Viren verhindern sollen, kosteneffizient einführen lassen, muss mit klar definierten Vorgaben abgeklärt werden. Der entsprechende Entscheid muss gemeinsam mit den involvierten Stakeholdern und auch aufgrund von Kosten-Nutzen-Überlegungen getroffen werden. Grundsätzlich gilt, dass es eine 100-prozentige Sicherheit in Bezug auf die Übertragung von Infektionserregern mit Blutprodukten nie geben wird.

Prevalence of chronic viral hepatitis infections in Karaj, Iran

Introduction

Viral hepatitis is challenging for health and blood safety. Studies carried out on blood donors can help find the frequency and trending of hepatitis B and C infections in a community and also safety of donation. The study aim is to determine the prevalence of HBV and HCV in Karaj blood donors over a four year period between 2010 to 2013.

Methods

This study reports the results of a cross sectional seroepidemiological study of hepatitis B and C in blood donors. Data on hepatitis infection and demographic characteristics of donors were gathered from blood donor registries. Frequency of hepatitis infections were described with 95% confidence interval. Chi square and logistic regression were used for analysis.

Results

The frequency of HBV and HCV infection in Karaj blood donors was 0.40% and 0.18% respectively. In first time donors, HBV and HCV positivity risk was respectively 3.59 and 4.8 fold in people with primary education (OR=3.59; 95% CI between 2.68-4.80) comparing to academic level. Frequency of hepatitis B has decreased significantly (P<0.001) during study period but frequency of Hepatitis C has not changed significantly.

Conclusion

The frequencies of HBV and HCV infection in Karaj blood donor population is low. There are equal infection rates within both genders. This must be considered in controlling transmission of infection in this area.

The infectious risks in blood transfusion as of today - A no black and white situation

Transfusion has been tainted with the risk of contracting an infection - often severe - and fears about this risk are still prevailing, in sharp contrast with the actual risk in Western countries. Those actual risks are rather immunological, technical (overload) or metabolic. Meanwhile, in developing countries and particularly in Africa, transfusion transmitted infections (TTIs) are still frequent, because of both the scarcity of volunteer blood donors and resources and the high incidence and prevalence of infections. Global safety of blood components has been declared as a goal to be attained everywhere by the World Heath Organization (WHO). However, this challenge is difficult to meet because of several intricate factors, of which the emergence of infectious agents, low income and breaches in sanitation and hygiene. This review aims at encompassing the situation of TTIs in different settings and means that can be deployed to improve the situation where this can possibly be.

[New viral risks in blood transfusion by 2016]

Viral safety remains a major concern in transfusion of blood products. Over years, the control measures applied to blood products were made more and more sophisticated; however, the number of infectious agents, and notably of viruses, that can be transmitted by transfusion is increasing continuously. The aim of this review paper is to actualize that published in the same journal by the same authors in 2011 with more details on some of actual vs virtual viral threats that were identified recently in the field of blood transfusion. The main subjects that are covered successively concern the transmission via transfusion of hepatitis E virus, the frequency of transfusion transmitted arboviruses, transfusion at the time of the Ebola epidemics in West Africa, the debated role of Marseillevirus (giant viruses infecting amoebae and suspected to infect human blood latently), and, finally, the recent report of the identification in blood donors of a new member of the Flaviviridae family. The addition of these new viral risks to those already identified-partially controlled or not-pleads for the urgent need to move forward to considering inactivation of infectious agents in blood products.

[Seroprevalence of hepatitis B and C viruses, HIV-1/2 and syphilis among blood donors in the Yaoundé Central Hospital in the centre region of Cameroon]

OBJECTIVES

Prevention of blood transfusion-transmitted infections includes blood donor screening and effective infectious markers screening for donated blood. This study had two main objectives: to determine seroprevalence of HBV, HCV, HIV and syphilis in blood donors of the Yaoundé Central Hospital and to study sociodemographic factors of blood donors.

PATIENTS AND METHODS

A retrospective study of consecutive blood donors' records from January to December 2013 was conducted. Seroprevalence of hepatitis B, hepatitis C, human immunodeficiency viruses and syphilis were determined in 9024 whole blood donations collected in the Yaoundé Central Hospital in the centre region, Cameroon using Elisa kits.

RESULTS

Mean age of donors was 28 years. The male to female ratio was 14.8. Most of blood donors were replacement donors (97.2%) and first-time donors (76.8%). Up to 19.3% of the donors tested positive for at least one infectious agent, in which 0.1% presented a positive test for three viruses (HIV, HCV and HBV). The overall seroprevalence in blood donors was 12.6% for HBsAg, 3.2% for hepatitis C antibody, 3.3% for HIV-1/2 antibodies and 0.2% for syphilis. The prevalence of HBsAg was significantly higher in men (P=0.001), among first-time donors (P=0.003), in blood group A (P=0.01) and those with the rhesus positive blood (P=0.01). The prevalence of anti-HCV was significantly higher among first-time donors (P=0.05). The prevalence of anti-HIV was significantly higher in first-time donors (3.7% vs 2.2%, P=0.02).

CONCLUSION

First-time blood donors and replacement donors are the two types of donors in Cameroon. Replacement donors are considered as having a major risk of transmission of infections to recipients. The seroprevalence of HIV, HBV, HCV, and syphilis among these donors is high and reflects how much these agents are present in Cameroon. Effective infectious markers screening and organization of blood donors into an association of volunteer's donors are necessary to secure blood transfusion in Cameroon.

[Evaluation of the efficacy of medical screening of blood donors on preventing blood transfusion-transmitted infectious agents]

BACKGROUND

The aim of this study was to evaluate the efficacy of medical screening to retain blood donors in window period by comparing the seroprevalence of infectious agents (HIV, hepatitis B and C, syphilis) in deferred versus accepted blood donors.

MATERIALS AND METHODS

This prospective and transversal study was performed during 4 months in the National Blood Transfusion Center in Dakar (Senegal). We conducted a convenience sampling comparing the seroprevalence of infectious agents (HIV, HBsAg, HCV and syphilis) in deferred versus accepted blood donors after medical selection.

RESULTS

In total, 8219 blood donors were included. Medical selection had authorized 8048 donors (97.92%) and deferred donors were 171 (2.08%). The prevalence of HIV was higher in the deferred than in accepted blood donors (1.75% vs. 0.05%) (P=0.0003; OR=35.91), as well as for HBsAg (12.87% vs. 7.35%) (P=0.006; OR=1.86). HCV antibodies were present in 0.71% of accepted blood donors and 0.58% in deferred blood donors (P=0.65; OR=0.82). Only accepted donors had brought the infection of syphilis (0.34%) (P=0.56; OR=0).

CONCLUSION

Medical selection is efficient to exclude blood donors at high risk of HIV transmission and to a lesser extent of HBV. However, current medical screening procedures do not allow us to exclude donors asymptomatic carriers of HCV and syphilis.

A Systematic Review and Meta-Analysis of the Clinical Appropriateness of Blood Transfusion in China

The issue of the clinical appropriateness of blood transfusion has become a focus of transfusion medicine worldwide. In China, irrational uses of blood have often been reported in recent years. However, to date there lacks a systematic review of the rational uses of blood. This study aimed to determine the clinical appropriateness of blood transfusion in China. We searched PubMed, Web of Science, the Cochrane Library, China National Knowledge Infrastructure (CNKI), China Science and Technology Journal Database, WanFang Database, and Chinese BioMedical Literature Database, and the retrieval cut-off date was June 31, 2015. SPSS 17.0 and MetaAnalyst 3.13 were employed as the statistics tools in this review. A pooled rate of clinical inappropriateness of transfusion was analyzed by DerSimonian-Laird method. In this study, a total of 39 observational studies were included, which related to 75,132 cases of blood transfusion. According to the meta-analysis results, the overall incidence of clinical inappropriateness of transfusion in China was estimated to be 37.3% (95% confidence interval [CI] [32.1, 42.8]). The subgroup analyses revealed that the pooled rates of clinical inappropriateness of transfusion of plasma, red blood cells (RBCs), cryoprecipitate, and platelets were 56.3% (95% CI [45.8, 66.2]), 30.9% (95% CI [27.1, 35.0]), 25.2% (95% CI [13.2, 42.7]), and 14.1% (95% CI [8.8, 21.9]), respectively. However, the pooled incidence of inappropriateness of transfusion in operative departments was 47.5% (95% CI [36.8, 58.3]), which was significantly higher than that in nonoperative departments, 25.8% (95% CI [18.7, 34.4], P < 0.05). The overall rates of inappropriate use were 36.7% (95% CI [30.2, 43.6]) in major cities and 37.5% (95% CI [31.2, 44.3]) in other cities, respectively; there was no statistically significant difference (P > 0.05). In conclusion, China has suffered from a disadvantage in the clinical appropriateness of blood transfusion, especially in plasma and RBC use. In future, comprehensive measures should be implemented in order to improve the clinical appropriateness of blood transfusion.

Zika virus and the never-ending story of emerging pathogens and transfusion medicine

In the last few years, the transfusion medicine community has been paying special attention to emerging vector-borne diseases transmitted by arboviruses. Zika virus is the latest of these pathogens and is responsible for major outbreaks in Africa, Asia and, more recently, in previously infection-naïve territories of the Pacific area. Many issues regarding this emerging pathogen remain unclear and require further investigation. National health authorities have adopted different prevention strategies. The aim of this review article is to discuss the currently available, though limited, information and the potential impact of this virus on transfusion medicine.