What happens to donated blood?

Pursuing their chief work--gathering, processing and distributing blood--the blood donor centres of the Canadian Red Cross Society follow standard operating procedures like those in place at the Ottawa centre. Here, recruitment staff and volunteers work to recruit donors to meet needs at a time when the number of donors is falling. When they register, donors must show proof of identity. Each receives a permanent identification number that is linked to the numbers assigned to the units of blood each donates and to the date the unit was collected and the centre that collected it. Donors must answer questions about health and high-risk activity, and the blood of those who report high-risk activity is not accepted. Units are screened by automated instruments for syphilis, hepatitis B and C, HIV types 1 and 2, and human T-cell leukemia virus. Units with a negative test result are broken down into components for use in hospitals. A reactive test result prompts quarantining of the unit and a second screening test. If this test result is also reactive, a sample of the unit is sent to the National Testing Laboratory for confirmatory testing, and the unit is discarded. Once it has the results of the confirmatory test, the centre contacts the donor. Blood is now considered a drug. Red Cross practices in Canada and around the world have been changing since 1989 to reflect this.     

Use of blood donation history of people with HIV infection to identify recipients at risk.

OBJECTIVE: To determine whether previous blood donations from HIV-positive patients posed a threat to recipients. DESIGN: Interviewer-administered questionnaire survey. SETTING: Regional HIV outpatient referral clinic for southern Alberta. PATIENTS: All 478 patients attending the clinic from May 1, 1993, to Mar. 31, 1994; 366 were excluded: 335 had not donated blood, and 31 could not provide reliable information regarding possible donations. INTERVENTIONS: Patients were asked at a routine clinic visit regarding the dates, frequency and location of previous blood donations. The Canadian Red Cross was informed, with patient consent, if the previous donations posed a potential risk of HIV transmission. OUTCOME MEASURES: Number of HIV-positive patients whose donations posed a possible or definite risk to recipients. RESULTS: A total of 545 units of blood had been donated by the 112 patients in the study; 57 units (donated by 29 patients) posed a possible risk, and 12 (given by 11 patients) posed a definite risk of HIV transmission to the recipients. Thirty-two of these donors had been unknown to the Red Cross through its "look-back" and "trace-back" protocols. Only 1 of the 13 patients found to be HIV positive by the Red Cross openly admitted donating blood to undergo HIV antibody testing; the remainder were either ill-informed or did not perceive themselves to be at risk. The patients were highly mobile, 36.7% donating blood at some time in a province other than the one where they had received their positive HIV test result. CONCLUSION: Asking HIV-positive patients about their blood donation history, although subject to recall bias, is a simple and inexpensive method for identifying high-risk blood donations. The Red Cross should routinely be notified, with patient consent, of all donations posing a risk in order to enhance the prospect for identifying HIV-positive blood recipients.     

Seroprevalence of Hepatitis B, Hepatitis C, HIV Infections in Blood Donors of Khulna, Bangladesh

To determine changes (Trends) in infection rates of Hepatitis B surface antigen (HBsAg), Hepatitis C virus (HCV) and Human immunodeficiency virus (HIV) in blood donors of Khulna Population. Specimens of 34953 voluntary blood donors & party or relative donors in Transfusion Medicine Department of Khulna Medical College Hospital from 2007 to 2009 were screened for HBsAg, anti-HCV, anti-HIV 1 & 2 reactivity in a cross-sectional survey by rapid test method. Reactive samples were verified using a recognized confirmatory test which consisted of a second generation enzyme immune assay (HBsAg), anti-HCV antibodies by anti-HCV EIA & for HIV by western Blot, respectively. The seroprevalence of HBsAg, Anti-HCV, HIV antibody 1 & 2 was 1.4%, 0.09% & 0.03% respectively in all blood donors. Prevalence of confirmed positivity was 0.62% for HBsAg, 0.04 % for Anti-HCV, 0.02% for HIV Western Blot. Between 2007 to 2009 a decreasing trend was observed in HBsAg frequency, HCV frequency decreased in 2009 compared to 2007. One HIV positivity found in 2009. Although the frequency of transfusion transmitted infections is low, party or relative donors have some risk factors than voluntary blood donors. Through more scrutiny in donor selection, improved serological test & reevaluation of infections routes in donor, infection reduction can be achieved.     

Registry of unrelated bone marrow donors.

Reports of successful transplantation of bone marrow obtained from unrelated donors who were histocompatibility leukocyte antigen (HLA) identical prompted the Canadian Red Cross Blood Transfusion Service in Ottawa to assess the possibility of developing a bone marrow donor registry in Canada. We sent a pamphlet that explained the program to 1568 people who had undergone apheresis and asked them to reply, stating their interest. At the same time the pamphlets and a poster were placed in the blood donor clinic. We received 1232 replies (78.6%) from the apheresis donors, 838 (68.0%) of which indicated a willingness to attend information sessions. Of the 7158 people who gave blood during the 3-month study period, 225 (3.1%) were interested. At the time this paper was written 47 information sessions had been held, and 721 people had attended, 624 (86.5%) of whom had signed a consent form. This indicates a clear interest in a bone marrow donation program. We believe that the ethical issues are overcome by requesting the donation before identification of any patient. From our experience a national registry of unrelated donors seems feasible, and steps are being taken to implement such a program.     

Seroprevalence of sexually transmitted infections among accepted and deferred blood donors in Jamaica

Critical donor selection and testing increases the safety of blood transfusion by excluding donors at risk of transmitting infections. This study investigated the seroprevalence of and risk factors for sexually transmitted infections (STIs) among accepted and deferred blood donors in Jamaica. A total of 1015 blood donors consisting of 794 (78%) accepted donors and 221 (22%) deferred donors presenting at the Central Blood Bank, Jamaica, over a six-month period, were recruited for this study. A standardized questionnaire was administered to each participant and a sample of blood obtained for detection of hepatitis B surface antigen, antibodies to Treponema pallidum, human immunodeficiency virus (HIV) and human T-cell lymphotrophic virus type-1 (HTLV-1). Deferred donors were three times more likely to be seropositive for STI than accepted donors (16.3% vs 5.2%, OR 3.57, 95% CI 2.16 - 5.90, p < 0.0001). Males had significant association between STI seropositivity and having fathered children with two or more women (p = 0.0085), unprotected sexual intercourse with several persons (p = 0.0326), and history of genital herpes (p = 0.0121). Significant risk factors identified among females were unprotected sex with several partners (p = 0.0385); having more than ten lifetime partners (p = 0.0105); and use of depoprovera (p = 0.0028). This study confirms higher rates of STI among deferred blood donors and supports the donor deferral system in Jamaica.     

A computerized national Blood Donor Deferral Register.

With blood given exclusively by volunteer donors, the American National Red Cross (ANRC) Blood Program aims to supply patients needing transfusion with blood products of the highest quality. The use of blood from volunteers, with its established greater safety, combined with laboratory testing to detect carriers of hepatitis B surface antigen (HB-SAg) and modern computer technology, creates an effective system to reduce the risk of post-transfusion hepatitis. The ANRC has devised a national Donor Deferral System, which is designed to minimize the transmission of hepatitis by blood and blood products.     

Rapid latex agglutination assay using recombinant envelope polypeptide for the detection of antibody to the HIV

Unscreened blood transfusions continue to be one of the major modes of transmission of the human immunodeficiency virus (HIV) in developing countries, such as in Central Africa, where 5% to 18% of blood donors are HIV seropositive. We evaluated a rapid latex agglutination assay using a novel recombinant envelope polypeptide of HIV for the detection of HIV antibodies among 2820 blood donors and clinical patients from diverse geographic regions, including on-site testing in Central Africa of 1600 blood donors. Overall, 29.2% of the serum samples were positive by Western blot assay. On a single determination, the latex agglutination slide test was found to be highly sensitive and specific compared with Western blot results in these populations with a relatively high prevalence of infection. Use of this assay will allow the immediate implementation of serologic screening for HIV in developing areas of the world, where standard screening procedures are impractical or not available, and in many other clinical settings, such as sexually transmitted diseases clinics and hospitals, where testing and counseling could be promptly implemented.     

基于HIV检测分析对无偿献血人群HIV筛查策略及归队的探讨

目的 对陕西省域内无偿献血者进行人类免疫缺陷病毒（human immunodeficiency virus,HIV）检测,分析省域内无偿献血人群HIV流行情况,以期为制定适宜的血液筛查策略和献血者归队方法提供数据与理论依据。方法 选定有区域代表性的陕西省西安市、延安市与安康市3家中心血站的无偿献血者血液样本进行2种四代酶联免疫吸附试验（enzyme-linked immunosorbent assay,ELISA）和病毒核酸检测（nucleic acid testing,NAT）HIV,将所有检测呈反应性的样本进行确证试验。结果 对290 341例无偿献血者进行HIV筛查,总计352例初检结果为不合格（含1例ELISA-/NAT+有反应性）,筛查反应率0.12%;所有样本送至属地市疾控中心检测,最终确证阳性11例（含核酸检测阳性1例）,确证阳性符合率3.79/10万。结论 陕西省域内无偿献血者中HIV阳性符合率低,提示目前无偿献血者HIV的血液筛查策略有待改进,同时也为献血者归队提供一定的理论支持。     

Prevalence of factor V Leiden in a Canadian blood donor population.

OBJECTIVE: To determine the prevalence of factor V Leiden in a Canadian blood donor population. DESIGN: Cross-sectional laboratory study. SETTING: Hamilton Centre of the Canadian Red Cross Society. PARTICIPANTS: Volunteer donors who attended Hamilton Centre blood donor clinics over a 4-day period in August 1994; blood samples from 356 people were evaluable. OUTCOME MEASURES: Presence of factor V Leiden. RESULTS: Factor V Leiden was detected in 19 of the 356 people, for a prevalence rate of 5.3% (95% confidence interval 3.0% to 7.6%). All 19 people were shown to be heterozygous for the mutation. CONCLUSION: Factor V Leiden is common in the Canadian population. Its prevalence is similar to that reported in other Western countries. These data are relevant in the clinical management of patients at risk for venous thrombosis and those with recurrent thrombotic disorders.     

Trends in incidence and prevalence of major transfusion-transmissible viral infections in US blood donors, 1991 to 1996. Retrovirus Epidemiology Donor Study (REDS)

CONTEXT: Evaluating trends in blood donor infectious disease rates is essential for monitoring blood supply safety and donor screening effectiveness. OBJECTIVE: To determine changes over time in blood donor population infection rates of human immunodeficiency virus (HIV), human T-lymphotropic virus (HTLV), hepatitis C virus (HCV), and hepatitis B virus (HBV). DESIGN: Cross-sectional survey data from the National Heart, Lung, and Blood Institute-sponsored Retrovirus Epidemiology Donor Study. SETTING: Five blood centers in different regions of the United States. PARTICIPANTS: A total of 1.9 million volunteer blood donors with 1 or more nonautologous donations from January 1991 to December 1996. MAIN OUTCOME MEASURES: Changes in rates of HIV, HTLV, HCV, and HBV infections were evaluated by comparing yearly prevalence estimates (per 100,000 donations) for first-time allogeneic donors and period-specific incidence rates (IRs) (per 100,000 person-years) for repeat allogeneic donors between 1991 and 1996 (for HCV, from about March 1992 to June 1996). RESULTS: Prevalence of HIV decreased in first-time donors from 0.030% to 0.015% (P=.006) and HCV prevalence decreased from 0.63% to 0.40% (P<.001). Trends were not statistically significant for the proportion of first-time donors with hepatitis B surface antigen (HBsAg) or HTLV. For repeat donors, IRs did not change significantly, indicating a stable but low level of seroconversion. The overall IRs (95% confidence intervals) per 100,000 person-years were 2.92 (2.26-3.70) for HIV, 1.59 (1.12-2.19) for HTLV, 3.25 (2.36-4.36) for HCV, and an estimated 10.43 (7.99-13. 37) for HBV (based on an HBsAg rate of 2.66 [2.04-3.41] with presumed false-positive results considered negative). The HBV IR estimate with presumed false-positive results considered positive (for comparability to previous analyses) was 17.83 (14.60-21.56). CONCLUSION: The decrease in HIV and HCV prevalence rates, combined with the previously documented lower rates of infection in first-time donors compared with the general population, suggests the continued benefit of behavioral risk factor screening. JAMA. 2000;284:229-235     

影响单采献血者保留的相关因素分析

目的 探讨影响单采血小板献血者保留的相关因素.方法 选择2015年1月1日到2015年12月31日到北京市血液中心成功捐献血小板的10 160例献血者作为研究对象,采集每个献血者的特征信息,即献血者献血时年龄、性别、献血状态(初次、非初次)和是否发生献血不良反应,分析其与下一年度献血者保留相关的两个变量的关系,即再次献血(是,否)和重复捐献的次数.结果 年轻献血者(＜25岁)献血返回率(26.4％)低于非年轻献血者返回率(47.2％),返回后献血次数低;女性献血者返回率(22.5％)低于男性献血者返回率(3.5％),返回后献血次数低;初次献血者返回率(24.3％)明显低于非初次献血者返回率(58.8％),返回后献血次数低,差异均有统计学意义(P＜0.001);是否发生不良反应与献血者返回无关(P＞0.05).结论 年轻、女性、初次献血与献血者返回呈负相关.建议针对这3类献血者采取相应措施增加单采献血保留率.     

Transfusion Transmitted Infections in Armed Forces: Prevalence and Trends

Background

This study presents data on the prevalence rate of infectious markers among voluntary and replacement donors in the blood transfusion service in Armed Forces from 2000 to 2004.

Methods

39,646 units of blood were collected from donors during the period from 2000 to 2004. All the samples were screened for hepatitis B surface antigen (HBsAg), human immunodeficiency virus (HIV) 1&2, hepatitis C virus (HCV), and by venereal disease research laboratory test (VDRL).

Results

24,527 (61.9%) were voluntary donations and 15,119 (38.1%) replacement donations. Prevalence of HBsAg had decreased, amongst voluntary donors from 1.67% to 0.77% but the positivity rate has not showed significant change. Seropositivity of HIV had decreased both in voluntary and replacement donors to 0.22% and 0.86% respectively. The seropositivity for anti-HCV showed steady decrease amongst voluntary donors from 0.46% to 0.20% in 2004, but in replacement donors, there was an increase in reactivity rate from 0.43% to 0.65%.

Conclusion

The increased seropositivity for HCV, HIV and HBsAg could be decreased by introduction of nucleic acid amplification testing (NAT) in minipools for HCV and HIV and introduction of anti-HBcAg (IgM) for hepatitis B virus (HBV) infection. But this may not be possible in near future in developing countries due to financial constraints. At present implementation of strict donor criteria and with use of sensitive laboratory screening tests it is possible to reduce the incidence of transfusion transmitted infections (TTI) in Indian scenario.Key Words: Transfusion transmitted infections, Human immunodeficiency virus, Hepatitis C virus, Hepatitis B virus     

Early Diagnosis of Human Immunodeficiency Virus Infection by p24 Antigen Detection

p24 antigen was estimated in human immunodeficiency virus (HIV) sero-negative individuals attending various sexually transmitted diseases (STD) clinics and also in sero-negative voluntary blood donors. A total of 300 STD cases and 500 voluntary blood donors, who also acted as controls, were included in this study. Antibody to HIV was detected by ELISA and was confirmed by western blot. In sero-negative individuals, p24 antigen detection was carried out by standard assay and immune-complex dissociation assay (ICD assay) using ELISA method and confirmation was done by neutralisation assay. In voluntary blood donors, 4 (0.8%) individuals were found to be HIV positive and no sero-negative individual was positive for p24 antigen. 41 out of 300 patients attending STD clinics were found to be positive for HIV and in 259 sero-negative patients, p24 antigen was detected in 6 (2.3%) cases by ICD assay whereas only 4 cases were detected by standard assay. By estimating p24 antigen an additional 2.3% HIV positive cases that were in window period were detected. Further, an ICD assay improves the detection of p24 positive individuals.Key Words: ICD assay, p24 antigen, STD, Window period     

献血人群感染TTV的检测及部分DNA序列分析

目的调查志愿无偿献血人群中输血传播病毒（TTV）的感染情况和分析TTV DNA部分基因序列。方法以TTV ORF1保守区设计两对引物,用巢式多聚酶链式反应（PCR）检测TTV DNA,并克隆和测序。结果在血液筛查合格的无偿献血人群中检出TTV DNA的阳性率为5．0％（5／100）。在单一转氩酶异常,HBV、HCV和HIV血清标记物正常的献血人群检出TTV DNA的阳性率为5．6％（4／71）。两者有非常显著性差异（P〈0．01）。与日本首例TTV-N22株相比,SZT1和SZT2株基因序列同源性为98．9％（3／272）和96．7％（9／272）,SZT3和SZT4株为67．3％（89／272）和86．0％（38／272）。结论在符合献血条件的人群中存在无症状TTV携带者。与之相比较,在ALT异常献血人群中TTV流行率相对较高,对其部分基因序列的比较显示了较大的变异性。     

湖北省仙桃市无偿献血血液标本检测情况分析

目的分析仙桃市无偿献血血液标本检测情况,探讨血液标本不合格因素及输血相关病原体感染的危险性,为临床安全用血提供技术支持。方法对仙桃市血站2006年1月～2010年12月31602名献血人员资料进行分析,比较不同性别、不同年龄献血者血液检测不合格率。结果无偿献血者血液总标本数31602份,检测合格标本数30330份,检测合格率为95．98％;检测不合格标本数1272份,检测不合格率为4．02％。其中ALT阳性检测不合格率2．13％;HBsAg阳性检测不合格率1．02％;抗-HCV阳性检测不合格率0．35％;SYP阳性检测不合格率0．38％;抗-HIV阳性检测不合格率0．15％。结论了解和掌握无偿献血群体、制定符合临床用血规律的采供血计划十分必要,而实行血液集中检测、严格筛查经血液感染性疾病直接关系到供血者的身体健康和受血者的安全,是提高临床安全用血的关键。     

Exogenous bacterial contamination of donor blood.

The Canadian Red Cross blood transfusion service has followed a set protocol for phlebotomy and collection of a unit of blood. Recent requirements for automated testing have necessitated that a second tube of blood be obtained from the blood line following collection of the unit. Evaluation of the techniques used, however, has indicated the possibility of bacterial contamination from the skin of donors, from insertion of the needle through an unsterile rubber stopper, and through backflow from a nonsterile vacuum tube. To test these possibilities swabs were taken from skin and stoppers of vacuum tubes. Further, vacuum tubes were deliberately contaminated with Escherichia coli. The normal sampling procedure, which involves stripping the donor line to refill and mix the blood, was then followed. This resulted in contamination of the segments and even the blood bag. These findings led to modification of the standard bleeding technique, whereby stripping was eliminated and sterile vacuum tubes were to be used at all times.     

A retrospective study of prevalence of antibody to HIV in blood donors at Ile-Ife, Nigeria

Records of voluntary and remunerative blood donors bled at the OAUTHC, Ile-Ife, Nigeria between January 1993 and December 2000 were reviewed for HIV sero-positivity. With a structured questionnaire, and over a period of 2 months, the attitudes and awareness of some of the donors of HIV/AIDS epidemic in the country were also assessed. Of the 16,080 units of blood collected in the period under review, only 1073(6.7%) were obtained from voluntary donors. The cumulative HIV seroprevalence rate was 2.1% in the paid donors as against 0.3% in the voluntary donors (c2 = 16.3, df = 1, p = 0.00003). Sixty-five (805) of the donors interviewed confirmed previous knowledge of HIV/AIDS before the interview. All the respondents appreciated the roles of blood transfusion in the transmission of AIDS viruses. The majority (74%) of the respondents were unemployed. Poverty was the reason given by 61(75%) of the commercial donors for selling their blood. We conclude that there is a greater risk of transmitting AIDS viruses (and possibly other blood transmissible diseases) through remunerated blood donors.     

HIV经输血传播的防范与献血跟踪策略

目的探索预防窗口期献血者导致输血传播HIV的方法.方法分析HIV感染窗口期的特点;论证献血跟踪策略（即血站采血后并不立即发出,而是将血液储存起来,并跟踪献血者自献血之日起到1个窗口期之后的1次HIV检验结果,只有跟踪结果阴性才能确认所采血液合格,否则不能发出.）的优越性.结果无法通过革新检测技术来消除HIV感染窗口期;病毒灭活技术也不能完全避免HIV经输血传播;献血跟踪策略的实施需要依赖血液长期保存技术、献血者的理解支持和法规政策的许可,而且会花费更多的检测费用和血液存储成本.但是,这一策略的实施,不仅可以掐断HIV经输血传播的渠道,还可以杜绝HCV、HBV等病原体经输血传播.结论献血跟踪策略是预防窗口期献血者导致输血传播HIV的有效方法,必然会赢得献血者和政策制定部门的支持.     

Markers of HIV infection prior to IgG antibody seropositivity

During a 1-year period of study at two plasma collection centers, 7 of 35,000 plasma donors seroconverted to the human immunodeficiency virus (HIV) and had stored plasma samples that predated or antedated the seroconversion period. From each donor, three to eight plasma samples that had been collected at 2- to 7-day intervals were tested for IgG and IgM antibodies to HIV with enzyme immunoassays, Western blot testing, and radioimmunoprecipitation assays. The presence of an HIV viremic phase was demonstrated by the infectivity of plasma on normal, phytohemagglutinin-stimulated peripheral blood mononuclear cells and by the detection of HIV antigen. In 5 of these donors, HIV antigen was detected prior to or simultaneously with IgG to HIV; these HIV-antigen-positive samples overlapped an IgM immune response. The disappearance of detectable HIV antigen, and to a lesser extent plasma infectivity, was concurrent with the development of an IgG immune response. Although the improved sensitivity of a recombinant DNA-derived anti-HIV screening assay shortened the "window period" between initial HIV infection and antibody detection, HIV antigen and plasma HIV viremia were the only markers of HIV infection for several days in 2 donors. These results demonstrate that HIV plasma viremia and antigenemia occur prior to seroconversion in healthy plasma donors.     

安阳地区无偿献血者及其中男男性行为人群HIV感染情况调查分析

目的 调查分析安阳地区无偿献血者及其中男男性行为(MSM)人群人类免疫缺陷病毒(HIV)感染情况.方法选取2008年1月至2015年12月安阳市中心血站440474例无偿献血者血液标本,使用酶联免疫吸附实验(ELISA)和免疫印迹法进行抗-HIV初筛与确证试验,调查分析MSM感染HIV的献血者相关资料,分析HIV感染率及初次献血和重复献血人群感染情况.结果 440474例无偿献血者中,共检出抗-HIV阳性献血者33例,HIV感染率为0.0075%;其中,通过MSM感染HIV 7例,占21.21%;MSM感染 HIV人群结构特征:年龄18 ~29岁占85.71%,大学以上学历占57.14%,在校学生占42.86%,未婚占85.71%;与历年HIV感染率比较,总体呈现上升趋势,差异无统计学意义(χ2=7.49,P>0.05);初次献血者MSM人群HIV感染率高于重复献血者,差异有统计学意义(χ2=8.54,P<0.05).结论 安阳地区无偿献血者HIV感染总体呈平稳低流行趋势,初次献血者MSM人群HIV感染率高于重复献血者.