严重发热伴血小板减少综合征病毒在输血安全中的研究进展

严重发热伴血小板减少综合征病毒(SFTSV),又名蜱虫病病毒,是近年来在我国部分地区传播的新发血液传播病毒,由病毒引起的严重发热伴血小板减少综合征具有较高的死亡率。献血者的病原体筛查是保障血液安全的重要手段之一。目前,我国采供血机构只筛查艾滋病病毒,乙肝病毒,丙肝病毒和梅毒螺旋体4种血液传播病原体,SFTSV等新发血液传播病原体可能威胁我国血液安全。我们将对SFTSV的病原学,检测方法和流行病学等方面进行综述,并进一步探讨SFTSV对我国血液安全的潜在威胁。     

血液成分光化学病原体灭活技术及其机制的研究进展

采用安全、可靠的技术对血液成分中病毒等病原体进行灭活处理,阻断血液筛查中漏检或某些未列入筛查范围的病原体的传播,这是杜绝输血传染病的重要手段,也是应对突发性的经输血传播感染性疾病的公共卫生事件最迅速有效的办法,如2002年FDA建议在血液筛查中增加检测美洲锥形虫之前亚甲蓝光化学法已被证实可部分     

重庆地区健康献血人群血液宏基因组分析与新发病原体鉴定

目的了解重庆地区健康无偿献血人群的微生物组,并调查可能存在的新发/再发病原体的流行情况,本研究利用深度测序的方法对重庆地区5 000人份健康无偿献血者标本进行了宏基因组学分析,以鉴定其中的新发/再发病原体。方法提取5 000人份血浆核酸总DNA,经随机引物扩增后,建库上机深度测序,用本课题组开发的Kraken Py软件分析宏基因组数据,并确定其中的微生物组,鉴定可能存在的新发/再发病原体。结果通过深度测序将获得的1.23 Gb的数据,其中包括2 146 844个有效读长,去人类DNA背景后,结果显示属于细菌的片段47条,属于病毒的片段21条,属于寄生虫的片段333条。最主要的病原体是刚地弓形虫(Toxoplasma gondii),其次是欧猥迭宫绦虫(Spirometra erinaceieuropaei),仅发现少量指环病毒科(Anelloviridae)的病毒成员如扭转病毒Torque teno virus等。另外,我们还发现在欧美发达国家已经被认为是能够造成输血安全威胁的病原体DNA片段,如疟原虫(Plasmodium spp.),婴儿利什曼原虫(Leishmania infantum)等。结论本研究结果显示了重庆地区健康无偿献血人群的微生物组结构,同时也揭示了这些健康献血者有可能携带的新发/再发病原体,提醒采供血系统工作者应结合当地新发传染病流行情况,合理的制定疫区或是传染病流行季节的筛查模式和献血者招募策略。另外,对于这些潜在风险也不必过于惊慌,因为这仅是微生物基因组片段结果,不代表该病原体仍具有感染性。     

输血传播病原体筛查技术应用研究进展

正经输血传播的传染病一直威胁着人类的生命和健康,也是对输血安全性的最大挑战。对献血者做输血传播疾病标志物的筛查是不仅是预防和控制其传播的重要手段,而且在保障输血安全中发挥着非常关键的作用。目前,全球不少国家都根据各自的传染病流行情况及国情制定了不同的血液病原体筛查策略。我国目前对献血者筛查的感染性疾病病原体共有HBV、HCV、HIV和梅毒螺旋体(TP)4种。在血液筛查过程中,检测效率及对病原体残余风险的控制与所应用     

加强安全输血的保障体系

安全输血是指从采血到输入血液或血制品到患者体内的整个过程中的安全保障,这是一个重要的公共卫生问题。据报道,美国每年有29 000万单位的血液成分被输入到49000万名患者体内[1]。我国每年临床用血量约为1 000多万单位。随着医疗技术的迅速发展和人民生活水平的不断提高,各国对血液的需求也日益增加。安全输血不仅影响受血者的身体健康和生活质量,而且对预防经血传播疾病的发生,保障社会稳定和建设和谐社会均具有重要意义。目前通过输血或血制品传播的病原体有人类免疫缺陷病毒1和2型(HIV 1、2)、人类T淋巴细胞白血病病毒(HTLV-Ⅰ/Ⅱ)…     

新余市血液筛查核酸检测实验室的建立

我国大部分采供血机构血液检测都是采用两个不同生产厂家的酶联免疫吸附试剂平行检测模式,采用酶联免疫吸附血清学两步法检测病原体所引起的抗体或抗原,大大减少了输血传播感染性疾病的风险。虽然该方法的灵敏度和特异性在不断地改进和提高,但每年仍有极少数新发输血后肝炎甚至HIV,其主要原因为病毒感染者"窗口期"献血、病毒变异、免疫静默感染及操作错误等引起,为了保证输血的安全性,欧美发达国家从1999年开始开展病毒核酸检测工作,数据表明HCV、HIV残余风险得到显著下降。我站于2010年开始探索应用核酸检测技术进行血液筛查,2011年建立起核酸检测实验室,2012年开展核酸检测工作,将其作为常规筛查项目,为临床用血安全提供有力保障。     

新型冠状病毒(SARS-CoV-2)对血液安全的影响

自2019年底至结稿,新型冠状病毒(SARS-CoV-2)在我国乃至全球持续蔓延,已成为全球地区重大的公共卫生威胁。目前科学家们已对SARS-CoV-2有了初步的了解,在对其传播途径的研究中发现,SARS-CoV-2具有潜伏期较长、无症状感染者较多的特点,这无疑是对当前血液安全的重大挑战。对于SARS-CoV-2能否经输血传播?如何保障疫情防控期间临床用血安全?如何降低新型冠状病毒经输血传播的风险?这些都是采供血机构关心和首要面对的问题。对比同为冠状病毒感染的严重急性呼吸道综合症(SARS)及中东呼吸综合症(MERS)有关血液安全的研究发现,并未发生过任何经呼吸道传播病毒经输血传播的报导,因此目前认为SARS-CoV-2能够经输血传播的风险仍是理论上的。但在疫情全面爆发的特殊时期,采供血机构可以自愿选择干预措施,最大限度的降低SARS-CoV-2经输血传播的风险,消除疫情期间人们对于血液安全的恐慌,保障临床用血安全。     

献血人群中巨细胞病毒感染与输血安全

巨细胞病毒(CMV)是感染全球很大一部分人的DNA病毒,通过多种途径传播,输血也是传播途径之一。CMV感染在免疫功能正常个体中,通常是无症状的,但在免疫功能受损或低下的患者中有很高的发病与死亡率。献血人群CMV血清学反应阳性比例较高,采供血机构应采取措施,如筛查CMV阴性献血者血液和/或白细胞减少,以及病原体灭活技术,防止CMV传播给有风险的患者。本文综述目前献血人群CMV检测方法,流行率,以及预防策略在输血传播CMV(TT-CMV)的效果。     

安阳地区无偿献血人群HIV输血风险评估

目的探讨经输血传播人类免疫缺陷病毒(HIV)的残余危险度,通过对现有筛查模式进行评价与分析,为提高输血安全提供科学依据。方法使用酶联免疫吸附实验(ELISA)和免疫印迹法(WB),对安阳地区2008-2014年的无偿献血者血液标本进行抗-HIV初筛与确认试验,使用数学模型法计算输血传播HIV的残余危险度。结果首次献血者HIV流行率为0.013 8(18/130 138),重复献血者HIV新发感染率为0.004 1(10/243 929);本地区无偿献血人群人类免疫缺陷病毒抗体阴性的血液传播HIV的残余危险度为1∶147 423;重复献血者传播HIV的残余危险度为1∶440 276。结论经输血传播HIV的危险性较低,但残余风险仍然存在。因此,应当进一步提高HIV检测技术和方法,缩短窗口期,进而提高血液筛查水平。建立固定、健康、低危的无偿献血者队伍,从血液源头降低输血风险。     

输血相关新发传染病

通过实施世界卫生组织的安全血液战略，特别是低危人群的无偿献血、严格的血液筛查等措施，输血传播疾病的发生率明显降低，其残余风险度已降至百万分之一以下。现在血液安全的风险主要来自新发传染病（emerging infectious diseases．EID），人们对这些疾病经输血传播的风险还缺乏认识，且尚未被列入常规筛查项目。     

The Impact of Emerging Infectious Diseases on Chinese Blood Safety

Emerging infectious diseases (EIDs) have always been one of the major threats to public health. Although the implementation of mandatory testing for 4 classical transfusion-transmitted infectious—human immunodeficiency virus, hepatitis B virus, hepatitis C virus, and syphilis—has reduced the transfusion risk of these pathogens, the potential threat of various EID agents and their constantly evolving variants to blood safety in China is not fully understood. This review presents 9 representative EID agents that are autochthonous and epidemic nationally or regionally in China. The epidemiologic status and distribution of these EID agents among donors and/or healthy populations are summarized. The potential risks of these EID agents to blood safety are discussed. The review also explores strategies to strengthen hemovigilance systems and studies to further evaluate the impact of EID agents on blood safety.     

The History and Challenges of Blood Donor Screening in China

Since the establishment of People's Republic of China in 1949, the Chinese government has encountered several catastrophes related to transfusion transmitted diseases. The government's increasing attention to blood safety has prompted the initiation of a series of policies and measures that have enhanced the level of safety for the blood supply and met the basic clinical demands of blood for 1.3 billion people in the country.Blood donation screening strategies in China predominantly comprise donor screening and donor testing. Donor screening includes selection of low-risk blood donors by the use of a donor history questionnaire, predonation physical examination, and initial rapid donor testing. Donor testing includes direct pathogen detection and serology tests. The year 1998 marked the most transformative change in blood donor selection and screening policies in China. Before 1998, paid donation was the predominant mode of blood donation. Donor screening and donor testing were conducted before donation, and only those who were eligible were allowed to donate. To ensure the safety of blood, donor testing was performed again after donation. After the implementation of the Blood Donation Law in 1998, to promote voluntary and unpaid donation, predonation donor testing was eliminated to reduce the amount of waiting time and to provide a more convenient donation experience for blood donors. However, it is the national requirement that donated blood should undergo 2 rounds of testing using different equipment or reagents, conducted by different personnel. Donor selection has transitioned from paid donation and obligatory donation to voluntary donation with fixed volunteer groups, as the latter mode of donation provides the lowest risks. Donations are currently screened for syphilis, hepatitis C virus, HIV, and hepatitis B virus (HBV). Units, previously typed only for ABO, are now routinely tested for both ABO and Rh(D). Innovations in testing technologies and methods have also brought changes to screening parameters. For instance, screening for HBV pathogens evolved from the early use of hemagglutination method to the later use of radioimmunoassay, independent enzyme-linked immunosorbent assay, and now the widespread application of nucleic acid test (NAT). Since 2010, the Chinese government has established NAT capacity in several blood centers; and in 2015, the government invested 900 million RMB on the nationwide expansion of NAT. Although the Chinese government has worked to enhance blood safety, many challenges remain. Concern exists for rising rates of HIV infection. The existence of occult HBV infection and the transmission of emerging blood-borne diseases continue to challenge the safety of the blood supply.     

Pathogen inactivation and removal methods for plasma‐derived clotting factor concentrates

Pathogen safety is crucial for plasma‐derived clotting factor concentrates used in the treatment of bleeding disorders. Plasma, the starting material for these products, is collected by plasmapheresis (source plasma) or derived from whole blood donations (recovered plasma). The primary measures regarding pathogen safety are selection of healthy donors donating in centers with appropriate epidemiologic data for the main blood‐transmissible viruses, screening donations for the absence of relevant infectious blood‐borne viruses, and release of plasma pools for further processing only if they are nonreactive for serologic markers and nucleic acids for these viruses. Despite this testing, pathogen inactivation and/or removal during the manufacturing process of plasma‐derived clotting factor concentrates is required to ensure prevention of transmission of infectious agents. Historically, hepatitis viruses and human immunodeficiency virus have posed the greatest threat to patients receiving plasma‐derived therapy for treatment of hemophilia or von Willebrand disease. Over the past 30 years, dedicated virus inactivation and removal steps have been integrated into factor concentrate production processes, essentially eliminating transmission of these viruses. Manufacturing steps used in the purification of factor concentrates have also proved to be successful in reducing potential prion infectivity. In this review, current techniques for inactivation and removal of pathogens from factor concentrates are discussed. Ideally, production processes should involve a combination of complementary steps for pathogen inactivation and/or removal to ensure product safety. Finally, potential batch‐to‐batch contamination is avoided by stringent cleaning and sanitization methods as part of the manufacturing process.     

Trends in major transfusion-transmissible infections among blood donors over 17 years in Istanbul, Turkey

Infection with hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV) and syphilis are serious complications of blood transfusion. These infections are routinely screened by blood banks; such tests are obligatory for transfusion safety in Turkey. The results of screening 1 737 943 blood donations from blood centres in Istanbul between 1 January 1987 and 31 December 2003 for HBV, HCV, HIV and syphilis were analysed retrospectively. Hepatitis B surface antigen rates fell from 5.98% in 1987 to 2.07% in 2003. Anti-HCV seropositivity was found to be approximately 0.5%, whereas anti-HIV seropositivity was approximately 0.001%. Rapid plasma reagin rates (test for syphilis) were 0.04% in 1987, and increased to 0.2% in 2002. The decreasing trends observed in data from the 17-year period studied indicate the value of safety measures taken, in particular the implementation of donor screening procedures in 1997.     

Number of recent sexual partners among blood donors in Brazil: associations with donor demographics, donation characteristics, and infectious disease markers

BACKGROUND: Brazilian blood centers ask candidate blood donors about the number of sexual partners in the past 12 months. Candidates who report a number over the limit are deferred. We studied the implications of this practice on blood safety. STUDY DESIGN AND METHODS: We analyzed demographic characteristics, number of heterosexual partners, and disease marker rates among 689,868 donations from three Brazilian centers between July 2007 and December 2009. Donors were grouped based on maximum number of partners allowed in the past 12 months for each center. Chi‐square and logistic regression analysis were conducted to examine associations between demographic characteristics, number of sex partners, and individual and overall positive markers rates for human immunodeficiency virus (HIV), human T‐lymphotropic virus Types 1 and 2, hepatitis B virus, hepatitis C virus, and syphilis. RESULTS: First‐time, younger, and more educated donors were associated with a higher number of recent sexual partners, as was male sex in São Paulo and Recife (p < 0.001). Serologic markers for HIV and syphilis and overall were associated with multiple partners in São Paulo and Recife (p < 0.001), but not in Belo Horizonte (p = 0.05, p = 0.94, and p = 0.75, respectively). In logistic regression analysis, number of recent sexual partners was associated with positive serologic markers (adjusted odds ratio [AOR], 1.2‐1.5), especially HIV (AOR, 1.9‐4.4). CONCLUSIONS: Number of recent heterosexual partners was associated with HIV positivity and overall rates of serologic markers of sexually transmitted infections. The association was not consistent across centers, making it difficult to define the best cutoff value. These findings suggest the use of recent heterosexual contacts as a potentially important deferral criterion to improve blood safety in Brazil.     

Demographic characteristics and prevalence of serologic markers among donors who use the confidential unit exclusion process: the Retrovirus Epidemiology Donor Study

BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect.     

2019年5月中国大陆需关注的突发公共卫生事件风险评估

目的评估2019年5月在我国大陆地区发生或者可能由境外输入的突发公共卫生事件风险。方法根据国内外突发公共卫生事件报告及重点传染病监测等各种资料和部门通报信息,采用专家会商法,并通过视频会议形式邀请省（自治区、直辖市）疾病预防控制中心专家参与评估。结果总体上,预计5月突发公共卫生事件的报告数将较4月有所上升,可能以水痘、手足口病、流行性腮腺炎、感染性腹泻等事件为主。 全国手足口病将进入流行高峰期。 登革热将继续出现境外输入病例,广东、浙江、海南和云南等高风险地区存在出现本地病例的可能,并可能出现小规模暴发疫情。 人感染禽流感疫情呈低发态势,仍可能继续出现人感染H7N9禽流感或其他亚型动物流感病毒散发病例。 食物中毒即将进入高发期,细菌性食物中毒及毒蘑菇中毒将增加。 刚果民主共和国埃博拉病毒病疫情仍将持续发生,但输入我国的风险低。结论需要对手足口病予以重点关注,对登革热、人感染禽流感、食物中毒、刚果民主共和国埃博拉病毒病予以一般关注。     

Bloodborne pathogens and procedure safety in interventional radiology

Concern about possible transmission of bloodborne pathogens during medical procedures is growing among patients and healthcare workers alike. This fear has primarily been focused on nosocomial transmission of human immunodeficiency virus (HIV), but other bloodborne infectious agents may also be transmitted during procedures. Chief among these are the hepatitis viruses, particularly hepatitis B virus (HBV) and hepatitis C virus (HCV), both of which are significantly more widespread than HIV. Although radiology is not traditionally thought of as a field with significant risk for exposure to or transmission of pathogens, the expanding role of interventional procedures in recent years belies that perception. The potential for exposure to blood or other possibly infectious material exists in virtually any invasive radiological procedure, from arteriography to image-guided biopsy. Fortunately, the risk of such exposure is low, and the risk of actual transmission of a bloodborne pathogen, whether from patient to healthcare worker or vice versa, is even lower. Nevertheless, it is important for all radiologists who perform invasive procedures to be aware of these risks and to observe pertinent safety and infection control recommendations. This article will review these topics.