Transfusion-associated Infection Research Articles

Adult People with Hemophilia A Have Low Annualized Bleeding Rate, However the Arthropathy Remains a Burden: A Retrospective Cohort Study.

Congenital Hemophilia A is a complex disease to treat, especially in places without access to hemophilia treatment centers (HTCs). The primary aim of this study was to analyze the outcomes of a cohort of adult people with congenital hemophilia A in an HTC localized in the Bajio region of Mexico. Observational retrospective study of a cohort of 82 adult people with congenital hemophilia A treated in a tertiary-level hospital in the Bajio region of Mexico, between June 2022 and June 2023. The median age of the patients was 29.5years, 60.9% with severe hemophilia A, 53.6% were under some factor VIII prophylaxis regimen, and 52.4% had home therapy. The median annualized bleeding rate (ABR) was one bleed/year (IQR 0-3 bleeds/year) including a median of zero joint bleeds/year (IQR 0-3 bleeds/year). The presence of high-response inhibitors was detected in 8.5%, with an overall incidence of inhibitors of 14.6% of the cohort. Univariate analysis showed that inhibitors (OR 21.10; CI 95% 1.20-370.3; P = 0.03) and clinical arthropathy (OR 6.14; CI 95% 2.13-17.68; P = 0.001) were significantly higher in severe hemophilia. Clinically significant arthropathy was found in 71.9% of patients. Ultrasonography of the target joints showed that mainly cartilage degeneration was affected. Blood transfusion-associated viral infections were detected in 10.9% of patients. In our HTC, current treatment with hemostatic agents allows adequate control of ABR with acceptable inhibitor rates. However, we still have joint damage in most patients, which is partly explained by the fact that prophylaxis was introduced only in recent years.

Global associations of key populations with HIV-1 recombinants: a systematic review, global survey, and individual participant data meta-analysis.

Global HIV infections due to HIV-1 recombinants are increasing and impede prevention and treatment efforts. Key populations suffer most new HIV infections, but their role in the spread of HIV-1 recombinants is unknown. We conducted a global analysis of the associations between key populations and HIV-1 recombinants. We searched PubMed, EMBASE, CINAHL, and Global Health for HIV-1 subtyping studies published from 1/1/1990 to 31/12/2015. Unpublished data was collected through a global survey. We included studies with HIV-1 subtyping data of key populations collected during 1990-2015. Key populations assessed were heterosexual people (HET), men who have sex with men (MSM), people who inject drugs (PWID), vertical transmissions (VERT), commercial sex workers (CSW), and transfusion-associated infections (BLOOD). Logistic regression was used to determine associations of key populations with HIV-1 recombinants. Subgroup analyses were performed for circulating recombinant forms (CRFs), unique recombinant forms (URFs), regions, and time periods. Eight hundred and eighty five datasets including 77,284 participants from 83 countries were included. Globally, PWID were associated with the greatest odds of recombinants and CRFs (OR 2.6 [95% CI 2.46-2.74] and 2.99 [2.83-3.16]), compared to HET. CSW were associated with increased odds of recombinants and URFs (1.59 [1.44-1.75] and 3.61 [3.15-4.13]). VERT and BLOOD were associated with decreased odds of recombinants (0.58 [0.54-0.63] and 0.43 [0.33-0.56]). MSM were associated with increased odds of recombinants in 2010-2015 (1.43 [1.35-1.51]). Subgroup analyses supported our main findings. As PWID, CSW, and MSM are associated with HIV-1 recombinants, increased preventative measures and HIV-1 molecular surveillance are crucial within these key populations. PROSPERO [CRD42017067164].

Hepatitis E virus seropositivity in an ethnically diverse community blood donor population.

Hepatitis E virus (HEV) is an underrecognized and emerging infectious disease that may threaten the safety of donor blood supply in many parts of the world. We sought to elucidate whether our local community blood supply is at increased susceptibility for transmission of transfusion-associated HEV infections. We screened 10,002 randomly selected donations over an 8-month period between 2017 and 2018 at the Stanford Blood Center for markers of HEV infection using commercial IgM/IgG serological tests and reverse transcriptase quantitative polymerase chain reaction assays (RT-qPCR). Donor demographic information, including gender, age, self-identified ethnicity, location of residence and recent travel, were obtained from the donor database and used to generate multivariate binary logistic regressions for risk factors of IgG seropositivity. A total of 10,002 blood donations from 7507 unique donors were screened, and there was no detectable HEV RNA by RT-qPCR. The overall seropositivity rate was 12.1% for IgG and 0.56% for IgM. Multivariate analysis of unique donors revealed a significantly higher risk of IgG seropositivity with increasing age, White/Asian ethnicities and residence in certain local counties. Although HEV IgG seroprevalence in the San Francisco Bay Area is consistent with ongoing infection, the screening of a large donor population did not identify any viraemic blood donors. While HEV is an underrecognized and emerging infection in other regions, there is no evidence to support routine blood screening for HEV in our local blood supply currently; however, periodic monitoring may still be required to assess the ongoing risk.

Prevalence of Asymptomatic Malaria Parasitemia among Blood Donors in Cape Coast, Ghana: A Cross-Sectional Study.

Malaria is an important transfusion-associated infection in many parts of the world, particularly in sub-Saharan Africa, where it is endemic. We studied the prevalence of malaria parasites among blood donors in the Cape Coast Metropolitan Area. A malaria parasite examination was added to the blood donor screening protocol for 240 voluntary and replacement blood donors (224 males and 16 females) between December 2020 and July 2021. Overall, 2.5% (6/240) had Plasmodium falciparum trophozoites detected in their blood sample. The remaining had no parasites detected. Four of the 148 who passed the blood donor screening tests were infected. The remaining two with malaria parasites failed one screening test. These included one donor with "hepatitis B + P. falciparum" and another with "syphilis + P. falciparum" parasite coinfection. All blood donors who had malaria parasites detected in their blood were males. Most donors, 45.8% (110/240), were in the 26-35 age group, with the highest prevalence of 1.3% (3/240). Blood group O was predominant (75.0%, 180/240), followed by B (12.9%, 31/240), A (11.3%, 27/240), and AB (0.8%, 2/240). All malaria parasites detected were among individuals with blood group O. Moreover, 96.3% (231/240) were rhesus-positive and had the highest prevalence of 2.1% (5/240). Screening of blood donors in Ghana does not include malaria, although there is the potential for transmission through blood products. Malaria transmission via blood transfusion remains an issue of public health concern, as indicated in the results of this current study. We recommend studies on malaria prevention, pretransfusion and posttransfusion, and pathogen reduction technology.

Understanding and management of adverse transfusion reactions

Blood transfusion is an essential supportive treatment in modern medicine and is frequently used. Acute hemolytic transfusion reaction is prevented by conducting a cross-matching test; however, nonhemolytic transfusion reactions are difficult to predict. Furthermore, adverse transfusion reactions are not sufficiently recognized by healthcare workers because they rarely occur, except for urticaria and febrile reactions. Thus, further awareness of adverse reactions, particularly regarding transfusion-associated circulatory overload, is needed. Since the introduction of irradiated blood, no transfusion-associated graft-versus-host-disease (TA-GVHD) case has been reported for over 20 years. However, education on the risk of TA-GVHD is important in facilities where nonirradiated blood is supplied or in situations such as unavoidable in-house blood collection on remote islands. The incidence of transfusion-transmitted hepatitis was significantly decreased by the introduction of nucleic acid amplification tests. Recently, the Japanese Red Cross Society is focusing on the reduction of transfusion-associated bacterial infections, which are rare but serious complications. This review provides an updated overview of adverse transfusion reactions and their management measures. Understanding adverse transfusion reactions will enable healthcare workers to recognize symptoms and take prompt action.

The Effect of Human Blood Plasma Conditioning Films on Platelet Transfusion Bag Surface Properties

Transfusion-associated bacterial infections continue to occur which may be due to the formation of bacterial biofilms on the inner surface of the blood bag. Plasticized poly (vinyl chloride) (p-PVC) platelet storage bags in three surface roughness states (rough, smooth and flattened) were used to determine the effect that a conditioning film (CF) of human plasma had on surface properties and its interaction with Staphylococcus epidermidis and Serratia marcescens. SEM and optical profilometry determined changes in surface roughness, whilst EDX and ATR-FTIR determined surface chemistry. The physicochemistry of the surfaces and bacteria was assessed using contact angle measurements and MATH assays respectively. When applied to a rougher surface, the CF reduced the surface topography, masked certain surface chemistry features and made the surfaces more hydrophilic. The CF reduced the adhesion of the bacteria to most of the hydrocarbons. When human plasma was combined with bacteria, most of the physicochemical properties changed similarly to those of human plasma alone, with the most significant changes observed after 24 h especially with Ser. marcescens. The results demonstrated that the presence of human plasma had a significant effect on the surface properties of the platelet bags and also on microbial interactions with the bag surface.

Milestones in the discovery of hepatitis C.

The discovery of hepatitis C has been a landmark in public health as it brought the opportunity to save millions of lives through the diagnosis, prevention and cure of the disease. The combined work of three researchers, Alter H, Houghton M and Rice C, which set the basis for the diagnosis, treatment and prevention of hepatitis C apart from laying the ground work for a new approach to study infections in general and developing new antiviral agents. This is a story of a transfusion-associated infection. A series of clinical studies demonstrated the existence of an infectious agent associated with hepatitis. That was followed by the identification of what was later known to be the hepatitis C virus (HCV) and the development of diagnostic tests. It all preceded the full molecular identification and demonstration of a causal effect. Finally it ended up with the development and discovery of a new class of therapeutic drugs, the direct acting antivirals, which are now used not only to cure the disease but most probably, to eliminate the problem. This work started with Dr Alter H who demonstrated that a new virus was responsible for the majority of post-transfusion hepatitis followed by Houghton M who cloned the virus and developed the blood test to identify those cases that carried the virus. Finally, the work of Rice C demonstrated that a cloned HCV produced after applying molecular biology techniques could cause long-standing infection and cause the same disease as the one observed in humans.

Hepatitis C Virus Infections in Patients with Hemophilia: Links, Risks and Management.

Haemophilia is a rare, hereditary bleeding disorder. Clotting factor concentrates were a revolutionary treatment which changed the life of people with haemophilia. However, early generation of clotting factor concentrates, without viral inactivation procedures in the manufacturing process, led to an increased risk of transmission of blood-borne viral infections, mainly due to hepatitis C virus and human immunodeficiency virus. As only 20% of HCV-infected patients clear the infection naturally, chronic HCV infection constitutes a serious health problem and a major cause of chronic liver disease in this group of patients. Fortunately, the use of viral inactivation procedures in the plasma-derived factor concentrates manufacturing process and the availability of alternative treatment options, led to a significant reduction of transfusion-associated viral infections. The advent of multiple, orally administrated, highly effective direct-acting antivirals (DAAs) is changing the natural history of HCV infection in patients with haemophilia as these drugs have an excellent safety profile and achieve very high sustained virological response rates, similar to the general population. Eradication of HCV-infection in patients with haemophilia is feasible via micro-elimination projects.

Primary membranous glomerulonephritis with negative serum PLA2R in haemophilia A successfully managed with rituximab \u2013 case report and review of the literature

BackgroundHepatitis C virus (HCV) and human immunodeficiency virus (HIV) cause a wide range of glomerular pathologies. In people with haemophilia, transfusion-associated infections with these viruses are common and definitive pathological diagnosis in this population is complicated by the difficulty of safely obtaining a renal biopsy. Membranous nephropathy (MN) is a common cause of adult onset nephrotic syndrome occurring in both primary and secondary forms. Primary MN is associated with podocyte autoantibodies, predominantly against phospholipase A2 receptor (PLA2R). Secondary disease is often associated with viral infection; however, infrequently with HIV or HCV. Distinguishing these entities from each other and other viral glomerular disease is vital as treatment strategies are disparate.Case presentationWe present the case of a 48-year-old man with moderate haemophilia A and well-controlled transfusion-associated HCV and HIV coinfection who presented with sudden onset nephrotic range proteinuria. Renal biopsy demonstrated grade two membranous nephropathy with associated negative serum PLA2R testing. Light and electron microscopic appearances were indeterminant of a primary or secondary cause. Given his extremely stable co-morbidities, treatment with rituximab and subsequent angiotensin receptor blockade was initiated for suspected primary MN and the patient had sustained resolution in proteinuria over the following 18 months. Subsequent testing demonstrated PLA2R positive glomerular immunohistochemistry despite multiple negative serum results.ConclusionsPursuing histological diagnosis is important in complex cases of MN as the treatment strategies between primary and secondary vary significantly. Serum PLA2R testing alone may be insufficient in the presence of multiple potential causes of secondary MN.

Transplant Tourism and Organ Trafficking: Current Practices, Controversies and Solutions

The controversial subject of transplant tourism has been neglected in the travel medicine literature. According to the Declaration of Istanbul, travel for transplantation can be regarded as transplant tourism if it involves organ trafficking and/or commercialised transplantation activities. While no registry of transplant tourism activities exists, published case series point to significant negative clinical outcomes. Adverse outcomes among donors include postoperative depression and anxiety, deterioration in health status, poor surgical wound care, and negative financial effects. Poor perioperative management, inadequate immunosuppression, blood transfusion-associated infections, antibiotic-resistant bacterial infections and invasive fungal infections, are among the most commonly reported complications in transplanted patients. Iran operates a legal and ethically regulated system of rewarded altruistic kidney donation. Travel medicine practitioners have a role to play in protecting the health of intending transplant tourists through targeted pre-travel health counselling and vaccination.

End-stage liver disease in persons with hemophilia and transfusion-associated infections

Many persons with hemophilia were infected with hepatitis C and B viruses (HCV, HBV) and HIV, but the consequences of these transfusion-acquired infections are poorly defined. We estimated the risk of HCV-related end-stage liver disease (ESLD) and the associations of age, HBV, and HIV with that risk. All 1816 HCV-seropositive hemophilic patients at 16 centers were followed for up to 16 years. Of these, 624 were HIV(-) and 1192 were HIV-coinfected; 135 had persistent HBV surface antigenemia, 1374 had resolved HBV infection, and 287 were HBV-uninfected. ESLD was defined as bleeding esophageal varices, hepatic encephalopathy, persistent ascites, or death excluding nonhepatic causes of these conditions. Competing risk models were used to estimate the annual hazard rate and cumulative incidence of ESLD. Proportional hazards models were used to estimate relative hazards of ESLD with covariates. ESLD developed in 127 of the HCV/HIV-coinfected participants, with an estimated 16-year cumulative incidence of 14.0% (95% confidence interval [CI], 11.6%-16.4%). Without HIV, 10 HCV-infected participants developed ESLD, for a significantly lower cumulative incidence of 2.6% (95% CI, 1.0%-4.3%, P <.0001). ESLD risk increased steeply with age in both groups. With HIV, ESLD risk was increased 8.1-fold (95% CI, 1.9-35.2) with HBV surface antigenemia, 2.1-fold (95% CI, 1.3-3.3) with fewer than 0.2 x 10(9)/L (200/microL) CD4(+) lymphocytes, and 1.04-fold (95% CI, 1.03-1.06) per year of age. Thus, HIV is associated with a markedly increased risk of HCV-related ESLD for persons with hemophilia, particularly with HBV infection, low CD4(+) lymphocytes, or older age.

Transfusion-Transmitted Malaria: A Systematic Review and Meta-analysis.

BackgroundMalaria transmission through blood transfusion is an accidental but preventable cause of malaria infection and is increasingly becoming a matter of concern for blood transfusion services. This systematic review was conducted to provide a summary of evidence about the prevalence of Plasmodium infection in asymptomatic blood donors and the effectiveness of screening methods used based on the available literature.MethodsPRISMA guidelines were followed. Scopus, PubMed, Science Direct, and EMBASE were searched from 1982 to October 10, 2017. All peer-reviewed original research articles describing the prevalence of malaria parasitemia in blood donors with different diagnostic methods were included. The random-effects model was applied to assess the effects of heterogeneity among the selected studies. Incoherence and heterogeneity between studies were quantified by I2 index and Cochran’s Q test. Publication and population bias was assessed with funnel plots and Egger’s regression asymmetry test. All statistical analyses were performed using Stata (version 2.7.2).ResultsSeventy-one studies from 21 countries, 5 continents, were included in the present systematic review. The median prevalence of malaria parasitemia among 984 975 asymptomatic healthy blood donors was 10.54%, 5.36%, and 0.38% by microscopy, molecular methods (polymerase chain reaction), and rapid diagnostic tests, respectively. The most commonly detected Plasmodium species was P. falciparum.ConclusionsThis systematic review demonstrates that compared with other transfusion-linked infections, that is, HIV, HCV, and HBV, transfusion-transmitted malaria is one of the most significant transfusion-associated infections especially in Sub-Saharan Africa. Future work must aim to understand the clinical significance of transfusion-transmitted malaria in malaria-endemic settings.

Risk of exposure to blood products during pregnancy: guidance for Zika and other donor deferral policies

Exposure to blood products during pregnancy carries a potential risk of transfusion transmission of infectious agents. Blood agencies have historically sought optimal deferral and testing strategies to protect blood supplies in part to ensure the protection of pregnant women and their unborn infants. The Zika virus outbreak of 2016 has heightened attention to these concerns. In the current context of the recent Zika outbreak, and also more broadly, data are needed to shed light on the likelihood of exposure to blood products throughout pregnancy to inform policy. Hospital administrative data from a large tertiary care center were examined for outpatient and nondelivery inpatient transfusion events in pregnant women between January 1, 2007, and December 31, 2013. Those pregnancies resulting in miscarriage were excluded from analysis. A total of 45,179 pregnancies resulting in delivery of a live or stillborn infant were documented at The Ottawa Hospital during the study period. Our findings indicate that 0.124%, or 1240 in 1,000,000, expectant mothers received transfusion at some point during their pregnancies with 0.04%, or 400 per 1,000,000, expectant mothers receiving a transfusion in the first trimester. Data from a large tertiary care center suggest that the risk of maternal and fetal exposure to blood products by transfusion during any stage of pregnancy is very low. Such a low likelihood of transfusion should be taken into consideration when developing donor deferral policies designed to protect women against transfusion-associated infection transmission during pregnancy and could inform evaluations of the risk of prenatal transfusion transmission of the Zika virus.

Cost-effectiveness of the screening of blood donations for hepatitis E virus in the Netherlands.

The incidence of hepatitis E virus (HEV) has increased substantially in Europe recently, thereby threatening blood safety. A cost-effectiveness analysis for HEV screening of blood donations in the Netherlands was performed. A simulation model was developed to mimic the process of donation, infections in the donor population, donation testing, and transmission to transfusion recipients. The variability of viral loads among donors was modeled using observed loads. The number of (incurable) chronic HEV infections among organ and stem cell transplant patients and the costs avoided by implementing blood screening were estimated. HEV screening of whole blood donations in pools of 24 would prevent 4.52 of the 4.94 transfusion-associated chronic HEV infections expected annually, at approximately €310,000 per prevented chronic case. Per case not curable by ribavirin prevention, costs are approximately 10 times higher. Selective screening, if logistically feasible, could reduce screening costs by 85%. Sensitivity analyses show that uncertainty in the HEV transmissibility and the frequency of HEV clearing greatly impact the estimated cost-effectiveness. Of all HEV infections nationwide one in 700 is estimated to be due to blood transfusion, while for chronic infections this is one in 3.5. Despite uncertainties in our estimates, preventing HEV transmission by screening of blood donations appears not excessively expensive compared to other blood-screening measures in the Netherlands. However, the impact on HEV disease burden may be relatively small as only a minority of all HEV cases is transmitted by blood transfusion.

Hepatitis E in blood donors: investigation of the natural course of asymptomatic infection, Germany, 2011.

Asymptomatic hepatitis E virus (HEV) infections have been found in blood donors from various European countries, but the natural course is rarely specified. Here, we compared the progression of HEV viraemia, serostatus and liver-specific enzymes in 10 blood donors with clinically asymptomatic genotype 3 HEV infection, measuring HEV RNA concentrations, plasma concentrations of alanine/aspartate aminotransferase, glutamate dehydrogenase and bilirubin and anti-HEV IgA, IgM and IgG antibodies. RNA concentrations ranged from 77.2 to 2.19×105 IU/mL, with viraemia lasting from less than 10 to 52 days. Donors showed a typical progression of a recent HEV infection but differed in the first detection of anti-HEV IgA, IgM and IgG and seropositivity of the antibody classes. The diagnostic window between HEV RNA detection and first occurrence of anti-HEV antibodies ranged from eight to 48 days, depending on the serological assay used. The progression of laboratory parameters of asymptomatic HEV infection was largely comparable to the progression of symptomatic HEV infection, but only four of 10 donors showed elevated liver-specific parameters. Our results help elucidate the risk of transfusion-associated HEV infection and provide a basis for development of screening strategies. The diagnostic window illustrates that infectious blood donors can be efficiently identified only by RNA screening.

Recent advances in liver disease.

Recent advances in liver disease.

Hepatitis E: Discovery, global impact, control and cure.

Hepatitis E was identified as an epidemic of non-A, non-B hepatitis from Kashmir, India in 1978. Hepatitis E virus (HEV), the etiological agent is the sole member of family Hepeviridae. The virus has marked heterogeneity and infects many animals like bats, camel, chicken, deer, boar, mongoose, pigs, rats, rabbit and cutthroat trout. Hepatitis E is a disease with a major global impact and has two distinct epidemiological patterns. Hepatitis E is an imperative health issue in developing nations, transmitted through sullied water and happens most every now in young adults. The disease is particularly severe during pregnancy and in people with underlying liver cirrhosis. Autochthonous hepatitis E is increasingly recognized in developed countries. The virus infects domestic pigs, wild boar and Sika deer in these countries. HEV infections in humans occur by eating the undercooked game flesh, raw liver from supermarkets and Figatelli sausages. Blood transfusion-associated HEV infections occur in many countries and screening of donors for HEV RNA is under consideration. Hepatitis E causes a number of extrahepatic diseases, including a wide spectrum of neurological syndromes. HEV genotype 3 causes prolonged viremia, chronic hepatitis, liver fibrosis and cirrhosis in organ transplant patients. The virus is amenable to ribavirin monotherapy and most patients clear the virus in a few weeks. Hepatitis E vaccine -239, marketed in China, has shown high efficacy with sustained protection for over four years.

Genotype Distribution and Molecular Epidemiology of Hepatitis C Virus in Hubei, Central China.

BackgroundLittle is known about the molecular epidemiology of hepatitis C virus (HCV) infection in Central China.Methodology/Principal FindingsA total of 570 patients from Hubei Province in central China were enrolled. These patients were tested positive for HCV antibody prior to blood transfusion. Among them, 177 were characterized by partial NS5B and/or Core-E1 sequences and classified into five subtypes: 1b, 83.0% (147/177); 2a, 13.0% (23/177); 3b, 2.3% (4/177); 6a, 1.1% (2/177); 3a, 0.6% (1/177). Analysis of genotype-associated risk factors revealed that paid blood donation and transfusion before 1997 were strongly associated with subtypes 1b and 2a, while some subtype 2a cases were also found in individuals with high risk sexual behaviors; subtypes 3b, 6a, and 3a were detected only in intravenous drug users. Phylogeographic analyses based on the coalescent datasets demonstrated that 1b, 2a, 3b, and 6a were locally epidemic in Hubei Province. Among them, subtype 1b Hubei strains may have served as the origins of this subtype in China, and 2a and 3b Hubei strains may have descended from the northwest and southwest of China, respectively, while 6a Hubei strains may have been imported from the central south and southwest.Conclusion/SignificanceThe results suggest that the migration patterns of HCV in Hubei are complex and variable among different subtypes. Implementation of mandatory HCV screening before donation has significantly decreased the incidence of transfusion-associated HCV infection since 1997. More attention should be paid to intravenous drug use and unsafe sexual contact, which may have become new risk factors for HCV infection in Hubei Province.

Molecular epidemiology of human Herpesviruses types 1-6 and 8 among Greek blood donors.

Human Herpesviruses (HHVs) maintain life-long latent persistence in the majority of the adult population including blood donors. The necessity for their study resides in the potential risk of transfusion-associated infection and the subsequent complications in the immunocompromised host. We aimed to assess the prevalence of HHVs types 1-6 and 8 among healthy blood donors of Thessaly prefecture in order to evaluate the frequency distribution of HHVs in Greek population and to ascertain possible correlations with demographic factors. Polymerase chain reaction (PCR) detection of HHVs DNA was determined in 401 randomly selected consecutive blood donors of Central Greece. Epidemiological data were recorded through a well structured questionnaire. The overall PCR positivity for HHVs was 25·4%. HHVs types 1-3 were not detected in any donor sample. A specimen with high level of HHV-6 DNA (1,580,400 copies per mL) was recorded. HHV-4 DNA positivity was significantly associated with rural residency. HHV-4 DNA is commonly detected in whole blood specimens of healthy individuals. HHVs types 5, 6 and 8 are rarely detected. However, the existence of a donor sample with high HHV-6 viral load raises questions regarding the potential risk of HHV-6 blood-borne infection and the safety of blood products.

HIV prevalence in blood donors and recipients in Pakistan: a meta-analysis and analysis of blood-bank data.

The first instances of HIV-antibody detection in donated blood in Pakistan were reported in 1988. Since then, documentation of HIV in blood donors and of rates of transmission via transfusion has been limited. Previously assumed to have a low prevalence, HIV is an increasing health concern in Pakistan. Since there is no national, centralized blood-banking system, there are no reliable data on which to base estimated risks of transfusion-associated HIV infection. This study was therefore conducted to estimate the prevalence of HIV in blood donors and recipients in Pakistan between 1988 and 2012. Meta-analyses were undertaken of reported prevalences of HIV in blood donors and recipients published during 1988-2012. Papers were identified by searching PubMed, Google, CINAHL and PakMediNet and the websites of the World Health Organization, the national HIV/AIDS Surveillance Project and the National AIDS Control Programme of Pakistan. In addition, the 1998-2012 records of the Aga Khan University blood bank were analysed. The 254 abstracts identified at the preliminary search were reviewed and, after removal of duplications, case-reports, editorials and reviews, 32 papers were selected that met the inclusion criteria. All studies that reported on HIV antibodies in blood donors/recipients were included, irrespective of the methodology used. Since seroconversion had only been confirmed through supplemental testing in a few papers, the results were analysed separately for reports based on screening only and confirmed cases. A total of 142 of 2 023 379 blood donors and 4 of 3632 blood recipients were HIV positive, giving an overall pooled seroprevalence of 0.00111% in blood donors and 0.00325% in blood recipients. The annual prevalences of HIV in donors at the Aga Khan University blood banks were similar, ranging from 0.013% to 0.116%. Very few reports on HIV in blood donors in Pakistan could be retrieved, and the overall pooled prevalence is low. However, the limited data and confounding factors mean that that these results may significantly underestimate the true situation. It is recommended that a complete survey of blood banks should be conducted throughout the country, in order to provide a more reliable estimate of the risk of transfusion-associated HIV infection in Pakistan.