Prevalence of and risk factors for hepatitis B and C infection among Mongolian blood donors

BACKGROUND: Mongolia has one of the highest rates of viral hepatitis infections worldwide yet risk factors have been largely unstudied. This sentinel study of hepatitis infection in Mongolia determined the prevalence of hepatitis B virus surface antigen (HBsAg) and hepatitis C virus antibody (anti-HCV) among a sample of blood donors and identified demographic and behavioral factors associated with hepatitis infection.
STUDY DESIGN AND METHODS: Data were collected by interview from 923 Ministry of Health Blood Center donors between August 2004 and February 2005. The exposure variables collected included donor demographics and health and behavioral risk factors. Bivariate and multivariate analyses assessed the prevalence ratio of hepatitis infection for each exposure.
RESULTS: Of 923 donors, 72 tested positive for HBsAg (7.8%; 95% confidence interval [CI], 6.1%-9.7%), 89 donors tested positive for anti-HCV (9.6%; 95% CI, 7.8%-11.5%), and six (0.6%) tested positive for both HBsAg and anti-HCV. Prevalence of HBsAg was highest among donors 18 to 19 years and anti-HCV tended to be most prevalent among those more than 40 years of age. Both pregnancy and alcohol use were associated with seroprevalent anti-HCV.
CONCLUSION: This sentinel study of hepatitis prevalence among Mongolian blood donors sheds considerable light on the epidemiology of hepatitis virus infection as well as the sociodemographic and behavioral risk factors associated with infection. Young age (HBsAg) and pregnancy (anti-HCV) were significant risk factors for hepatitis virus infection, indicating that improvements in education, vaccination rates, and general infection control procedures in health care institutions may reduce behavioral and nosocomial transmission.     

Prevalence of HLA antibodies in remotely transfused or alloexposed volunteer blood donors

BACKGROUND: HLA antibody testing of previously transfused or pregnant donors may help reduce the risk of transfusion‐related acute lung injury (TRALI). However, the prevalence of HLA antibodies in transfused donors has not been well characterized. STUDY DESIGN AND METHODS: Transfusion and pregnancy history was obtained from consenting donors. HLA Class I and II antibody testing was performed by multiantigen bead Luminex platform. Cutoff values for Class I and II antibodies used normalized background ratios of 10.8 and 6.9, respectively. Linear probability models were used to evaluate potential associations between HLA alloimmunization and donor characteristics. RESULTS: A total of 7920 donors (2086 males and 5834 females) were tested. HLA antibody prevalence did not significantly differ between 895 transfused (1.7%) and 1138 nontransfused males (1.0%; odds ratio [OR], 1.75; 95% confidence interval [CI], 0.80‐3.82]. Prevalence in 45 transfused nulliparous females (4.4%; 95% CI, 0.1%‐11.8%) was not different from the 1.6% prevalence in 1732 nontransfused nulliparous females (OR, 2.94; 95% CI, 0.68‐12.74). Transfused parous females had higher prevalence than nontransfused counterparts (p = 0.004; OR, 1.39; 95% CI, 1.07‐1.80). In a linear probability model, the estimated additive risk of transfusion‐induced alloimmunization was only 0.8% (95% CI, ?0.2% to 1.8%; p = 0.10). Donor transfusion history showed that 58% of transfusions occurred more than 10 years previously. CONCLUSION: Transfused volunteer blood donors do not appear to have a significantly higher prevalence of HLA antibodies than their nontransfused counterparts. Thus, in an effort to reduce TRALI risk, ascertaining past history of transfusion and testing these donors for HLA antibodies is not necessary.     

Worse quality of life in volunteer blood donors with hepatitis C

BACKGROUND: Health-related quality of life (HRQOL) encompasses many different aspects of health perceived by the individual, and its alterations in patients with hepatitis C virus (HCV) have been recently reported. The objective was to study a population of volunteer blood donors at different stages of HCV liver disease. STUDY DESIGN and METHODS: The Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36), a generic tool, was used to evaluated HRQOL. The SF-36 scores of HCV patients were compared with those of matched healthy blood donors and at the sixth month in those who were submitted to antiviral treatment. Sex, drug use, and alcohol consumption were also evaluated. A total of 120 HCV chronic carriers were divided into three groups: 1) patients with no indication for liver biopsy (n = 37); 2) patients submitted to liver biopsy with mild liver disease (n = 40); and 3) patients with moderate to severe liver disease submitted to interferon plus ribavirin treatment (n = 43). RESULTS: HCV patients had significantly lower SF-36 scores when compared with matched healthy blood donors. There was no correlation between SF-36 scores and history of intravenous and/or inhaled drug use or alcohol consumption. Women had lower SF-36 scores than men in six domains. At the sixth month of treatment, patients who continued to be positive for the presence of HCV RNA (nonresponders) had lower quality of life than those who became HCV RNA-negative. CONCLUSION: Healthy blood donors with HCV showed significantly reduced HRQOL that was more marked in women. The presence of the virus is one of the possible explanations for the reduced HRQOL.     

Risk factors in hepatitis C virus-infected blood donors

Risk factors of parenteral and nonparenteral exposure to hepatitis C virus (HCV) infection were studied in 125 blood donors in The Netherlands who were positive for anti-HCV on enzyme-linked immunosorbent assay (ELISA). Risk factors were related to confirmatory test results of four-antigen recombinant immunoblot assay (4-RIBA) and polymerase chain reaction (PCR) of the HCV 5' untranslated region. Twelve (10%) of the 125 anti-HCV C100 ELISA-positive blood donors were 4-RIBA positive. Eleven (92%) of 12 4-RIBA-positive blood donors were PCR positive, and all 113 remaining 4-RIBA-negative or -indeterminate donors were PCR negative. Eleven (92%) of 12 4-RIBA-positive blood donors had a risk factor of parenteral exposure, as compared to 17 (15%) of 113 4-RIBA-negative or -indeterminate donors. The prevalence of confirmed HCV infection among Amsterdam blood donors is calculated at 0.04 percent; parenteral exposure appears to be the major risk factor for HCV infection.     

Prevalence and epidemiological characteristics of hepatitis C in Scottish blood donors

SUMMARY. All blood donors in Scotland who were found to be infected with hepatitis C virus (HCV) in the first 6 months of routine testing of all donations for anti-HCV were contacted. Those who attended were counselled, a history of exposure to risk was sought, and blood was taken for alanine aminotransferase (ALT) level as a measure of liver function. The epidemiological features were then correlated with the virological findings and ALT.
In the period under study between September 1991 and February 1992, 180658 blood donors attended. The prevalence of HCV infection was 0.088%. Of the 151 donors who attended for counselling, 101 (68%) were male. Intravenous drug use was the most common risk activity (39%), followed by previous blood transfusion (15.2%), other parenteral exposure (11.2%) and heterosexual contact with a parenterally infected partner (8.6%); 29.1% of donors gave no history of possible exposure.
Elevated ALT levels were found in 59%. ALT levels were higher in donors with HCV types 1 and 3 than in HCV type 2 or non-viraemic donors.
The prevalence of HCV in Scottish blood donors is thus relatively low. This may relate to the effectiveness of donor selection procedures, but donors with risk activities which should debar them continue to donate. The combination of ALT and PCR appears to be useful in counselling and assessing infected donors.     

献血者感染HBV相关危险行为因素的调查研究

目的研究献血者感染乙肝病毒(HBV)的相关危险因素。方法对203名单纯HBsAg阳性的献血者及406名所有血液检测项目均阴性的献血者进行对照研究,应用多因素条件Logistic回归模型分析与HBV感染有关的因素,并对危险因素的人群归因危险度(PAR)进行估计。结果筛选出5项与感染HBV有关的因素,研究发现使用共用剃刀、乙肝家族史、内窥镜检查史、牙科治疗史、未注射乙肝疫苗可以增加乙肝感染的危险性,其危险度(OR)分别是:4.010 2、2.808 2、5.815 7、1.758 3、4.044 4,人群归因危险度分别是:43.39%,5.50%,1.75%,13.46%,29.91%。5项危险因素总的人群归因危险度为66.78%。结论使用共用剃刀、乙肝家族史、内窥镜检查史、牙科治疗史、未注射乙肝疫苗是HBV感染的危险因素。     

Recombinant immunoblot and polymerase chain reaction testing in volunteer whole blood donors screened by a multi-antigen assay for hepatitis C virus antibodies

The purpose of this study was to compare the results of supplementary testing of volunteer whole blood donors who had been screened by the first hepatitis C virus antibody assay licensed in the United States with results from donors screened by a newer, more sensitive, multi- antigen assay. In contrast to the earlier assay, the multi-antigen assay incorporates a recombinant hepatitis C virus antigen, c22-3, which is encoded by a structural region of the viral genome. Supplementary testing included a second-generation recombinant immunoblot assay and a highly sensitive polymerase chain reaction assay for evidence of hepatitis C virus genomic RNA. A comparison of supplementary test results reveals a higher percentage of donors screened by the newer assay to be indeterminate on recombinant immunoblot (34.4% vs. 6.4%, p < 0.05). Furthermore, polymerase chain reaction testing of donors with indeterminate blot results shows that 14 percent have evidence of viral RNA. For this reason, counseling of donors with indeterminate patterns on immunoblot must include informing them of the possibility that they are infected.     

Prevalence of antibodies against hepatitis B and C virus among pregnant women and female blood donors in Sweden

The prevalence of elevated alanine aminotransferase (ALT) levels and antibodies against hepatitis B and C virus (HBV and HCV) among 755 pregnant women attending a prenatal clinic was studied. Consecutive female presumptive blood donors (n = 649) served as serological controls. Among the pregnant women 85 (11%) had elevated serum ALT levels. Antibodies against HCV (anti-HCV) were detected in six (0.8%) pregnant women in a screening enzyme-linked immunosorbent assay (ELISA) and with consecutive confirmatory test (RIBA-2). Antibodies against HBV (anti-HBc and/or anti HBs) was found in 63 (8.3%) pregnant women, of whom three (0.4%) were HBsAg positive. Among the blood donors anti-HCV was detected in seven (1%) of whom one (0.15%) was positive in the confirmatory test (RIBA-2). None of the blood donors had any serological marker of HBV exposure as measured by HBsAg and anti-HBc. The anti-HCV prevalence among pregnant women was low and did not differ significantly from that of healthy blood donors. Prenatal screening for hepatitis is concluded not to be justified without having a history of risk exposure or risk behaviour.     

Prevalence of hepatitis C virus and genotype distribution in an Australian volunteer blood donor population

BACKGROUND: This study was undertaken to assess the prevalence of hepatitis C virus (HCV) antibody and RNA in first-time blood donors and to examine the HCV genotype distribution. STUDY DESIGN AND METHODS: A third-generation enzyme-linked immunosorbent assay (ELISA) was used to screen 34,725 donors for HCV antibodies. Donors who were repeatably reactive were tested in two immunoblot assays-a second-generation and a third-generation recombinant immunoblot assay-as well as by a polymerase chain reaction (PCR) assay. PCR-positive donors were genotyped. All samples were screened for alanine aminotransferase levels. RESULTS: The ELISA repeat reactivity rate was 0.55 percent. PCR testing showed that 69 (38%) of the 183 ELISA-reactive samples contained HCV RNA. The third-generation recombinant immunoblot assay identified all 69 viremic samples as antibody positive; however, only 63 tested positive on the second-generation immunoblot. The remaining six PCR-positive donors tested antibody-indeterminate to the core peptide. All six of these donors had HCV subtype 3a infections. Genotype distribution among 58 samples showed that 34 were type 1, of which 22 could be further subtyped as 1a (16) and 1b (6); 2 were 2a; 5 were 2b; and 17 were subtyped as 3a. Donors infected with 2b and 3a had reduced antibody reactivity to the NS4 and NS3 peptides only on the second-generation immunoblot. CONCLUSION: The prevalence of confirmed anti-HCV and viral RNA in new donors is 0.29 and 0.2 percent, respectively. The third-generation recombinant immunoblot assay was more sensitive than the second-generation immunoblot assay in detecting 2b and 3a HCV subtypes. The inclusion of the NS5 peptide in the third- generation recombinant immunoblot did not result in positive tests in any additional donors. Rather, the improvement was due to the increased detection of NS3 and, to a lesser extent, NS4 antibodies. Subtypes 1a and 3a were most prevalent in this population.     

Prevalence of serologic markers for hepatitis B and C viruses in Brazilian blood donors and incidence and residual risk of transfusion transmission of hepatitis C virus

BACKGROUND: We evaluate the current prevalence of serologic markers for hepatitis B virus (HBV) and hepatitis C virus (HCV) in blood donors and estimated HCV incidence and residual transfusion‐transmitted risk at three large Brazilian blood centers. STUDY DESIGN AND METHODS: Data on whole blood and platelet donations were collected from January through December 2007, analyzed by center; donor type; age; sex; donation status; and serologic results for hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti‐HBc), and anti‐HCV. HBV and HCV prevalence rates were calculated for all first‐time donations. HCV incidence was derived including interdonation intervals that preceded first repeat donations given during the study, and HCV residual risk was estimated for transfusions derived from repeat donors. RESULTS: There were 307,354 donations in 2007. Overall prevalence of concordant HBsAg and anti‐HBc reactivity was 289 per 100,000 donations and of anti‐HCV confirmed reactivity 191 per 100,000 donations. There were significant associations between older age and hepatitis markers, especially for HCV. HCV incidence was 3.11 (95% confidence interval, 0.77‐7.03) per 100,000 person‐years, and residual risk of HCV window‐phase infections was estimated at 5.0 per million units transfused. CONCLUSION: Improvement in donor selection, socioeconomic conditions, and preventive measures, implemented over time, may have helped to decrease prevalence of HBV and HCV, relative to previous reports. Incidence and residual risk of HCV are also diminishing. Ongoing monitoring of HBV and HCV markers among Brazilian blood donors should help guide improved recruitment procedures, donor selection, laboratory screening, and counseling strategies.     

Prevalence and risk factors associated with hepatitis C in ED patients

The objective of this study was to measure the prevalence of and identify risk factors associated with hepatitis C virus (HCV) in emergency department (ED) patients. Adults presenting to an urban university teaching hospital, having blood drawn as part of their routine evaluation, had an extra tube drawn and tested for HCV. English-speaking adults consenting to participate in the survey portion of the study were administered an in-depth risk factor questionnaire. A case-control analysis was used to identify risk factors in HCV+ compared with HCV- subjects. Contingency table analyses using the Fisher exact test, odds ratios (OR), and 95% confidence intervals (CI) were used for risk factor identification. Of 223 blood samples, 38 (17%) were positive for antibodies for HCV. One hundred twenty-one subjects (54%) agreed to the risk factor survey, 18 (15%) of whom were HCV+. Of the 18 HCV+ survey participants, 12 new diagnoses of HCV were made. A history of injection drug use was the most significant risk factor associated with HCV (OR 858.5, CI 61.8-22,026.5). A high prevalence of HCV is found in selected urban ED patients. Most of these patients have a constellation of risk factors including a history of injection drug use. Efforts to identify at risk patients for serologic testing and follow-up should be initiated. Identifying undiagnosed HCV can lead to interventions to decrease transmission as well as reduce the morbidity and mortality of disease.     

Risk factors for hepatitis C virus infection among blood donors in northern Thailand

BACKGROUND: The epidemiology, virology, and risk factors for hepatitis C virus (HCV) infection among blood donors in northern Thailand have not been extensively evaluated. STUDY DESIGN AND METHODS: We did a prospective matched case-control study of blood donors who tested positive for HCV and were confirmed by recombinant immunoblot assay or nucleic acid testing. Infected donors were matched with one to four HCV-uninfected donors for sex, age +/- 5 years, and donation at the same site within 15 days of the HCV-positive donor. Married donors were invited to bring their spouse for HCV testing. RESULTS: Among 166 matched sets, a history of intravenous drug use (IDU), reported by 58 HCV infected donors (35.5%) and 2 HCV-negative donors, was strongly associated with HCV infection (odds ratio [OR], 107.6; 95% confidence interval, 14.8-780.7). In multivariate analysis among donors without a history of IDU, significant risk factors included a history of a blood transfusion (OR, 28.8), immediate family with a history of hepatitis/jaundice (OR, 4.4), six or more lifetime sexual partners (OR, 2.7), and increased frequency of blood donation (OR, 0.9). Six of 45 spouses of HCV-infected donors, and none of 44 spouses of uninfected donors, were HCV positive (p = 0.005). CONCLUSION: Our data indicate that illicit IDU and a history of transfusion are important risk factors for HCV infection in Thailand. Also, our data suggest there may be some risk of transmission by sex or other close contact between spouses.     

Prevalence of antibodies to hepatitis B core antigen and occult hepatitis B virus infections in Korean blood donors

BACKGROUND: This study was performed to determine the prevalence of antibodies to hepatitis B core antigen (anti‐HBc) among Korean blood donors and frequencies of hepatitis B virus (HBV) DNA and antibodies to hepatitis B surface antigen (anti‐HBs) in anti‐HBc–positive donors. STUDY DESIGN AND METHODS: A total of 12,461 consenting blood donors were consecutively enrolled from Korean Red Cross Blood Services from April to October 2008. All of the donors were screened for anti‐HBc with an electrochemiluminescence immunoassay. Repeat‐reactive anti‐HBc–positive donors were assayed for anti‐HBs and for HBV DNA using a multiplex test (Cobas TaqScreen, Roche Molecular Systems) on individual donation. RESULTS: Of the 12,461 donors, 1682 (13.5%) were reactive for anti‐HBc. Among different age groups, there was a steady increase in the anti‐HBc–positive rate, ranging from 2.0% in the age group of less than 20 years to 80.0% in the age group of 60 years and older (p < 0.0001). Of the anti‐HBc–positive donors, 1523 (90.5%) were anti‐HBs positive. HBV DNA was detected in two donors who were anti‐HBc positive and hepatitis B surface antigen negative. The prevalence of occult HBV infection was 0.016%, and the HBV nucleic acid test (NAT) yield was 1 in 838 (0.12%). CONCLUSION: This study helps to determine the current status of hepatitis B infection and the prevalence of occult HBV infection in the blood donor population in Korea. We estimate that in Korea, up to 161 units per million donated units from blood donors may contain HBV DNA. Although the potential infectivity of these units has been debated upon, the HBV NAT assay could prevent certain transfusion‐transmitted HBV infections.     

某地区无偿献血者中性粒细胞特异性抗体筛查分析

目的探讨河南地区无偿献血者中性粒细胞特异性(HNA)抗体的分布和特异性,分析HNA抗体引起的免疫性输血不良反应。方法随机收集女性标本156例,男性标本80例,采用LABScreen Multi试剂盒对标本HNA抗体进行检测。结果 236例无偿献血者中,女性HNA抗体检出阳性率为5.77%(9/156),男性为5.00%(4/80)。其中HNA 1A者7例,HNA4A者4例,同时检出HNA 1A和HNA 4A、HNA 1A和HNA 1C各1例。结论 HNA抗体分布无性别差异,研究HNA抗体的分布和特异性,可为指导临床用血安全和相关政策的制定提供有力的理论基础。     

Prevalence of antibodies to human T-lymphotropic virus types I and II in volunteer blood donors and high-risk groups in northwestern Greece

BACKGROUND: In addition to human immunodeficiency virus, human T- lymphotropic virus types I and II (HTLV-I/II) is prevalent among blood donors in the United States. In Greece, there are no epidemiologic data regarding the prevalence of HTLV-I/II among volunteer blood donors and high-risk groups. STUDY DESIGN AND METHODS: To determine the prevalence of HTLV-I/II infections in northwestern Greece, a seroepidemiologic study was conducted among volunteer blood donors, multiply transfused patients, heroin addicts, and chronic hemodialysis patients. The subjects were tested for serologic evidence of HTLV-I/II infection by enzyme immunoassays and specific protein immunoblot confirmatory test. RESULTS: None of the volunteer blood donors and heroin addicts had detectable antibodies to HTLV-I/II. Only 1 (1.45%) of the 69 multiply transfused patients had indeterminate results, while 2 (1.2%) of 163 hemodialysis patients were positive. CONCLUSION: In northwestern Greece, routine screening for HTLV-I and HTLV-II infections does not appear to be required. However, the finding of seropositivity among hemodialysis patients requires further evaluation of the origin of the infection, as its zero prevalence in this population seems to exclude transfusion transmission.     

Prevalence and infectivity of hepatitis G virus and its strain variant, the GB agent, in volunteer blood donors in Taiwan

BACKGROUND: The prevalence of hepatitis G virus (HGV) and its strain variant, the GB agent (GBV-C) is high in non-virus-inactivated plasma products, but, persistent infection in recipients is relatively low. STUDY DESIGN AND METHODS: Stored samples from transfusion donors and recipients in a prospective study of posttransfusion hepatitis were tested for HGV RNA and antibody to the E2 protein (anti-E2). RESULTS: Thirty-two (2.1%) of the 1500 qualified donors were positive for HGV RNA. Twenty-four persons had received a transfusion of blood from one of these 32 viremic donors. Of these 24 recipients, 3 were positive for HGV RNA before transfusion. Of the remaining 21 recipients, 8 became viremic after transfusion, while the other 13 were not infected. Four of the eight infected recipients were persistently positive for HGV RNA, while four became negative in 1 to 3 years. Three of the four patients with HGV clearance seroconverted to anti-E2 positivity. Comparison of the viral titer, viral sequences at E2, storage period of blood donations, and clinical data in the infected and noninfected recipients revealed no significant differences. However, the noninfected recipients seemed to have a higher prevalence of anti-E2 before transfusion. CONCLUSION: The prevalence of HGV viremia in volunteer blood donors in Taiwan is 2.1 percent, and blood from 0.6 percent of them actually causes HGV infection in the recipients. In half of infected recipients, clearance of HGV occurs. Anti-E2 appears in most recipients whose viremia is cleared.