献血者中TTV感染情况调查及部分序列分析

目的调查了解淮阴地区献血者中一种新的肝炎相关病毒——TTV的感染情况.方法用巢式聚合酶链反应(nest-PCR)技术对淮阴地区220名专业献血者进行血清中输血传播病毒(TTV)的检测,并在PUC18中对其开放读码框2(ORF2)基因进行了克隆.结果序列分析表明,该序列与国内外发现的TT病毒AB008394(日本株)、AF079173(中国河北株)对应位置核苷酸同源性为98%和97%,献血者中TT病毒阳性率为18%.结论病毒ORF2基因高度保守,献血者中有较高的TTV感染率.     

The status of blood safety in ECO member states

Background

Access to the information concerning blood safety is essential for managing problems and overcoming the challenges that are faced in any given region. Information on the availability and safety of blood in countries of the Economic Cooperation Organisation (ECO) is largely lacking. To address this problem, the Iranian Blood Transfusion Organisation, in collaboration with other ECO member states, initiated a research project in 2009 to collect, analyse and compare statistics on blood safety in the region.

Materials and methods

A modified and summarised version of the Global Database on Blood Safety (GDBS) questionnaire was used to collect data. The questionnaire was sent to all ten countries in the ECO region. The heads of the national transfusion services or focal points were requested to complete the form. Related literature and websites were also reviewed.

Results

Only three countries (Afghanistan, Iran and Turkey) completed the questionnaire, while other countries provided their available data on some parts of the questionnaire. The number of donations per year varied from 5 to 27/1,000 population. The rate of donors positive for human immunodeficiency virus ranged from 0.003% to 0.2%. The rate of donors positive for hepatitis C virus antibody varied from 0.05% to 3.9% while that of hepatitis B virus surface antigen ranged from 0.15% to 3.91% respectively.

Discussion

There is very clear diversity in blood transfusion services among ECO member states. Most countries in the region do not have a data-recording system. It is generally estimated that the need for blood is much higher than the supply in this region. Deficiencies in donor screening and a high prevalence of transfusion-transmitted infections are other important challenges.     

Determination of the degree of bacterial contamination of whole-blood collections using an automated microbe-detection system

BACKGROUND: The prevalence of bacterial contamination in whole-blood collections, either with immediate sampling or sampling after overnight storage as whole blood at 20 degrees C, is determined. STUDY DESIGN AND METHODS: Whole blood was collected under blood bank conditions in special five-bag systems, allowing sampling in a closed system for culture bottles. Samples were taken within 2 hours after collection (Group 1) or after overnight storage of the whole blood at 20 degrees C (Group 2). Culture bottles were incubated for 7 days, and positive samples were entered on agar plates for confirmation and determination. RESULTS: In Group 1, 9219 units were tested; 27 units were positive with positive subculture, that is, 0.29 percent with a 95% CI of 0.19 to 0.42 percent. In Group 2, 9038 units were tested; 36 units were positive with positive subculture, that is, 0.39 percent with a 95% CI of 0.28 to 0.55 percent. No significant difference could be found between the two test groups. The majority of bacteria were either Staphylococcus (all coagulase-negative) or Propionibacterium species. CONCLUSION: For a total of 18,257 units, 0.34 percent (CI, 0.25-0.44) of whole-blood collections appeared to have bacterial contamination (mainly skin-derived). Overnight storage of whole blood at 20 degrees C did not have a significant effect on the prevalence of bacterial contamination.     

Transfusion transmitted Yersinia enterocolitica infection in New Zealand

Abstract Aims: To update and summarise cases of transfusion-transmitted Yersinia enterocolitica infection in New Zealand and to evaluate critically suggested methods to reduce this rare but frequently fatal complication of blood transfusion.
Methods: Case reports of four recent transfusion-transmitted Y enterocolitica infections in New Zealand are given and previous reports reviewed. Literature review and evaluation of proposed methods to decrease the incidence of transfusing yersinia contaminated blood.
Results: There have been eight cases of transfusion-transmitted Y enterocolitica infection in New Zealand in the past five years. Four of the five deaths have been directly caused by the transfusion. This gives a transfusion incidence rate of one:65,000 and a fatality rate of one: 104,000 units transfused. This fatality rate is more than 80 times higher than that reported in the United States.
Conclusions: Why the incidence of transfusion-transmitted yersinia is so high is not clear, since we do not store blood as long as many other countries, particularly the United States. In Auckland, however, the cases came at a time when the number of yersinia isolates from the community is reported to be rising.
Many suggestions for the prevention of this problem have been put forward reflecting the fact that there is as yet no perfect solution. Those which are easy to implement and cheap to perform are largely already in place and investigation is continuing into the other alternatives.     

经输血传播病毒的前瞻性调查

目的了解我国供血员、受血者中经输血传播病毒（ＴＴＶ）感染率,及经输血传播ＴＴＶ的发生率。方法对１３０例输血者进行ＴＴＶ以及ＨＢＶ和ＨＣＶ血清标志物检测,其相应的供血者也检查ＴＴＶ。结果３４０例供血员中有３６例（１０．６％）可检测到ＴＴＶ－ＤＮＡ。１３０例受血者输血前有１１例（８．５％）ＴＴＶ阳性,其余１１９例输血后有１８例ＴＴＶ转为阳性,在他们的供血中至少可查到一份ＴＴＶ阳性。４６例输血后肝炎病毒感染者中,其中有４５例为ＨＣＶ感染（包括７例与ＴＴＶ混合感染）,２例为ＨＢＶ感染（包括与ＨＣＶ、ＴＴＶ混合感染各１例）。ＴＴＶ与ＨＢＶ混合感染以及７例ＴＴＶ与ＨＣＶ混合感染中有３例的受血者ＡＬＴ＞９０Ｕ／Ｌ,但是１０例单纯ＴＴＶ感染者,仅有２例伴有轻微的ＡＬＴ增高。结论供血员及住院病人中有较高的ＴＴＶ感染率,单纯ＴＴＶ感染与ＡＬＴ显著升高似乎并无关联。     

5334例受血者输血前血液传染性疾病检测的意义

目的：探讨受血者输血前经血液传播性疾病感染检测的意义。方法：对5334例受血者输血前用微粒酶免疫法检测抗HIV和抗HCV，采用双夹心抗体酶联免疫吸附法检测梅毒抗体。结果：输血前受血者抗HIV阳性率0．26％，抗HCV阳性率1．18％，梅毒抗体阳性率0．41％。结论：受血者输血前作血液传染性疾病检测，能对受血者的健康状况作出判断，减少和杜绝医原性感染，防止医患纠纷，是一项对医患双方有自身保护作用的措施。     

非甲至非戊型肝炎患者TTV检测和部分基因序列分析

目的：研究新近报道的一种与输血后肝炎有关的病毒在中国郑州地区正常人群、HBsAg阳性者、非甲至非戊型肝炎患者中的感染和基因序列变异情况。方法：采用TTV基因组ORF1区的套式聚合酶链反应(nested-PCR)方法对血清标本进行检测,并对非甲至非戊型肝炎患者中的TTV分离株进行序列测定。结果：TTV DNA在非甲至非戊型肝炎患者中检出率为45％(18／40);在正常体检者中检出率为17．7％(17／96);在HBsAg阳性者(ALT≤34 IU／L)中检出率22．7％(10／44)。TTV分离株序列与日本株(CLON22)相对应位置的核苷酸同源性为．1％。结论：TTV在非甲至非戊型肝炎患者TTV的感染率明显高于其他人群,可能是非甲至非戊型肝炎的主要致病因子。