Declining value of alanine aminotransferase in screening of blood donors to prevent posttransfusion hepatitis B and C virus infection. The Retrovirus Epidemiology Donor Study

BACKGROUND: Since the mid-1980s, blood banks in the United States have screened donors for elevated alanine aminotransferase (ALT) in an effort to prevent posttransfusion hepatitis. The present study was designed to quantitate the residual value of ALT screening following the implementation of hepatitis C virus (HCV) assays. STUDY DESIGN AND METHODS: Two approaches were used. First, a database of 2.3 million donations made by 586,507 volunteer blood donors between 1991 and 1993 was used to compare the incidence of seroconversion to hepatitis B virus (HBV) and HCV marker positivity in donors with elevated ALT values and with normal ALT values. Second, the duration of ALT elevation prior to HBV and HCV seroconversion was determined from 34 well-documented cases of posttransfusion HBV and HCV; elevated-ALT window periods were multiplied by rates of HBV and HCV incidence in donors to project the yield of ALT screening. Predictive value and cost- effectiveness analyses were also performed to compare the value of ALT screening before and after HCV screening was implemented. RESULTS: Both approaches indicate that ALT testing does not detect HBV in the window phase but does currently identify approximately 3 HCV window-phase donations per 1 million donations; this contrasts with ALT detection of approximately 1800 HCV-infectious units per 1 million donations prior to anti-HCV screening. Currently, only 8 in 10,000 donated units with elevated ALT (negative anti-HCV) are infected with HCV. The cost of continued ALT screening was estimated at $7,931,000 per quality- adjusted year of life saved. CONCLUSION: The yield, predictive value, and cost-effectiveness of ALT screening of blood donors have declined dramatically with the implementation of progressively improved anti-HCV assays. ALT screening of volunteer blood donors should be discontinued.     

Transmission of serologically silent hepatitis B virus along with hepatitis C virus in two cases of posttransfusion hepatitis

The polymerase chain reaction (PCR) was used to investigate the presence of hepatitis B virus (HBV)-related DNA sequences in blood from three blood donors and two transfusion recipients who developed posttransfusion non-A, non-B hepatitis (NANBH). In the first case, the sole donor was positive for antibody to hepatitis B surface (HBs) and core (HBc) antigens and had elevated alanine aminotransferase (ALT) levels, while the recipient had no HBV serologic markers. Both the donor and the recipient had serologic markers of hepatitis C virus (HCV) and were found positive for HBV DNA and HCV RNA sequences by PCR. The second case involved two donors and one recipient. Serologic tests for conventional HBV markers were negative in all three individuals, but one of the donors had elevated ALT. HBV DNA sequences were detected by PCR in the serum of the recipient and of the donor with high ALT, but not in the serum of the donor with normal ALT. Anti-HCV was detected in the serum of the recipient and of the suspect donor but not in that of the donor with normal ALT. The sequences amplified in the S region and determined after cloning of PCR products for both donor-recipient pairs were indistinguishable from each other and identical to the sequence of the major HBV subtype of adw in the first case and ayw in the second case. Furthermore, for the second case, an identical single-point mutation was found in both the donor and the recipient. These data confirm the transmission of conserved HBV sequences together with HCV in posttransfusion NANBH.(ABSTRACT TRUNCATED AT 250 WORDS)     

Impact of nucleic acid testing for hepatitis B virus, hepatitis C virus, and human immunodeficiency virus on the safety of blood supply in Italy: a 6-year survey

BACKGROUND: Nucleic acid testing (NAT) for hepatitis C virus (HCV) and human immunodeficiency virus (HIV) has been implemented in several European countries and in the United States, while hepatitis B virus (HBV) NAT is still being questioned by opinions both in favor and against such an option, depending on the HBV endemicity, health care resources, and expected benefits. STUDY DESIGN AND METHODS: This survey was aimed to assess the NAT impact in improving the safety of blood supply in Italy, 6 years after implementation. The study involved 93 Italian transfusion centers and was carried out in 2001 through 2006. A total of 10,776,288 units were tested for the presence of HCV RNA, 7,932,430 for HIV RNA, and 3,405,497 for HBV DNA, respectively. RESULTS: Twenty‐seven donations or 2.5 per million tested were HCV RNA–positive/anti‐HCV–negative; 14 or 1.8 per million units tested were HIV RNA–positive/anti‐HIV–negative; and 197 or 57.8 per million donations tested were HBV DNA–positive/hepatitis B surface antigen–negative. Of the latter, 8 (2.3/10⁶) were collected from donors in the window phase of infection and 189 (55.5/10⁶) from donors with occult HBV. Sixty‐eight percent of the latter donors had hepatitis B surface antibody, 74.5 percent of whom with concentrations considered protective (≥10 mIU/mL). CONCLUSION: NAT implementation has improved blood safety by reducing the risk of entering 2.5 HCV and 1.8 HIV infectious units per million donations into the blood supply. The yield of NAT in detecting infectious blood before transfusion was higher for HBV than for HCV or HIV. However, the benefit of HBV NAT in terms of avoided HBV‐related morbidity and mortality in blood recipients needs to be further evaluated.     

Impact of individual-donation nucleic acid testing on risk of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus transmission by blood transfusion in South Africa

BACKGROUND: In 2005, the South African National Blood Service introduced individual-donation (ID) nucleic acid test (NAT) screening for human immunodeficiency virus (HIV) RNA, hepatitis C virus (HCV) RNA, and hepatitis B virus (HBV) DNA. At the same time the use of ethnic origin to prioritize the transfusion of blood according to a hierarchy of residual risk was discontinued.
STUDY DESIGN AND METHODS: ID-NAT (Ultrio on Procleix Tigris, Chiron) and serology (PRISM, Abbott) repeat test and confirmation testing algorithms were designed to enable differentiation between false-positive and true-NAT and -serology yields. After 1 year, the NAT and serology yield rates in first-time, lapsed, and repeat donors were analyzed and used to estimate the residual risk of HIV, HBV, and HCV infections by blood transfusion.
RESULTS: The HIV, HBV, and HCV ID-NAT window phase yield rates in 732,250 blood donations were 1:45,765, 1:11,810, and 1:732,200, respectively. Seven of 16 HIV window phase donations with viral loads above 16,000 copies/mL were HIV p24 antigen enzyme-linked immunosorbent assay positive. PRISM detected anti-HIV and hepatitis B surface antigen (HBsAg) in 89.4 and 73.9% of early infections in repeat donors. The Procleix assay detected viremia in 99.7 and 95.5% of anti-HIV– and HBsAg-positive first-time donors. In these donors, the occult HBV DNA carrier rate was 1:5200. The residual transmission risk of ID-NAT HIV, HBV, and HCV window phase donations was estimated at 1:479,000, 1:61,500, and 1:21,000,000 respectively.
CONCLUSION: One-year ID-NAT screening of 732,250 donations interdicted 16 HIV, 20 HBV, and 1 HCV window phase donations and 42 anti-hepatitis B core antigen–reactive infections during an early recovery or a later stage of occult HBV infection.     

Transfusion-transmitted hepatitis E caused by apparently indigenous hepatitis E virus strain in Hokkaido, Japan

BACKGROUND:  In industrialized countries, sporadic cases of hepatitis E have been reported in individuals who have never been in an endemic area. Hepatitis E virus (HEV) infection commonly occurs via the fecal-oral route but a potential risk of transfusion transmission route has been suggested.
STUDY DESIGN AND METHODS:  A 67-year-old Japanese male patient who had never been abroad received a transfusion of blood from 23 voluntary donors and developed acute hepatitis with unknown etiology after transfusion. His blood samples were tested for viral markers of hepatitis viruses.
RESULTS:  HAV, HBV, HCV, CMV, and EBV were ruled out as causative agents in this case. The patient's blood sample in the acute phase contained HEV RNA as well as IgM and IgG anti-HEV. HEV RNA was also detected in one of the FFP units transfused. The donor had no history of traveling abroad and had a normal ALT level at the time of donation. The PCR products from the patient and the donor showed complete identity for two distinct regions of HEV within open reading frame 1.
CONCLUSION:  The patient was infected with HEV via transfused blood from a volunteer donor. A potential risk of posttransfusion hepatitis E should be considered even in nonendemic countries.     

上海地区无偿献血者乙肝病毒核酸检测分析

目的了解无偿献血者乙肝病毒核酸筛查(NAT)阳性人群特点,为血液安全策略提供参考。方法无偿献血者血液经Murex和科华HBsAg ELISA试剂检测,结果为阴性的血液使用cobas TaqScreen MPX试剂进行HBV DNA,HCV RNA,HIV RNA 3项联合核酸检测。对于MPX反应性标本,使用COBAS AmpliPrep/TaqMan进行核酸鉴别试验,同时使用罗氏ECL电化学发光检测系统进行乙肝补充血清学试验。结果 2011年11月1日～2012年1月31日3个月共有献血者86 375人(次),其中有63 351人(次)为初次献血者,HBsAg反应性为1.04%,23 024人(次)为重复献血者,HBsAg反应性为0.46%,两者差异有统计学意义(χ2=63.63,P0.05)。84 990份HBsAg、抗-HCV、抗-HIV1/2阴性血液进行MPX核酸检测,共发现52例(0.060%)HBV DNA阳性,均为低拷贝,含量为(20～200)IU/ml间,其中32例(0.051%)来自初次献血者,20例(0.087%)来自重复献血者,两者比例差异无统计学意义(χ2=3.65,P0.05),没有发现HCV RNA与HIV RNA阳性。结论重复献血者HBsAg反应性比率低于初次献血者;HBsAg阴性献血者HBV DNA阳性率为0.060%,重复献血者HBV DNA阳性率与初次献血者比较,两者差异无统计学意义;开展HBV核酸检测能够进一步保障血液安全。     

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.     

High-throughput HBV DNA and HCV RNA detection system using a nucleic acid purification robot and real-time detection PCR: its application to analysis of posttransfusion hepatitis

BACKGROUND: A high-throughput detection system was developed for HBV DNA and HCV RNA. METHODS: A combination of real-time detection PCR using an automated system (PRISM 7700, PE Biosystems, Foster City, CA) and automatic viral nucleic acid extraction (BioRobot 9604, Qiagen, Hilden, Germany) was used as the high-throughput detection system. An internal control for HBV DNA detection was also developed. RESULTS: Testing of 96 samples for HBV and HCV was completed within 5 hours. The sensitivity of this system almost equals that of the manual method using nested PCR. The addition of an internal control for HBV detection did not affect the sensitivity of the method and confirmed the accuracy of results. It was possible to quantify HBV in HBV+ samples that contain more than 500 genome equivalents per mL. We started using this system from June 1999 for testing stored donor and patient samples to analyze cases of posttransfusion hepatitis and identified three HBV+ donations that were implicated in posttransfusion hepatitis B. CONCLUSION: The high-throughput detection system is a useful tool for HBV DNA and HCV RNA detection because it enables rapid and reliable testing of a large number of samples.     

Limited utility of alanine aminotransferase screening of hepatitis C antibody-screened blood donors

BACKGROUND: The introduction of hepatitis C virus (HCV) screening has significantly reduced the frequency of posttransfusion hepatitis C. To examine the current added value of alanine aminotransferase (ALT) screening, all donor screening at two large blood centers was reviewed. STUDY DESIGN AND METHODS: From July 1991 through March 1994, 1,258,000 allogeneic blood donors were screened by enzyme immunoassay for anti- HCV: 343,000 donations by the first-generation test (HCV 1.0) and 915,000 donations by the second-generation test (HCV 2.0). Donations with positive EIA results were confirmed with a recombinant immunoblot assay. RESULTS: Of these donors, 1,637 (0.13%) were confirmed as HCV- positive and 21,666 (1.72%) had elevated ALT. To estimate the additional margin of safety due to ALT screening, all donors who seroconverted were reviewed, and those donors who had elevated ALT but were HCV negative on a previous donation were identified. One hundred eleven HCV seroconversions were observed: 19 seroconversions from HCV 1.0-negative to HCV 1.0-confirmed-positive, 82 apparent seroconversions from HCV 1.0-negative to HCV 2.0-confirmed-positive, and 10 seroconversions from HCV 2.0-negative to HCV 2.0-confirmed-positive. The number of apparent HCV 1.0-negative to HCV 2.0-positive seroconversions was much greater than expected, which reflected the increased sensitivity of HCV 2.0. Only 15 donors were identified who had an elevated ALT on a previous HCV-negative blood donation, and all of these were among those who apparently seroconverted from HCV 1.0- negative to HCV 2.0-confirmed-positive. Out of the 10 HCV 2.0- seroconverting donors, no donor was found who was initially HCV 2.0 negative with elevated ALT and later was HCV 2.0 positive; nor were such donors found among 4 additional HCV 2.0-seroconverting donors. CONCLUSION: With the introduction of HCV 2.0 screening. ALT appears to have little value as a surrogate test for hepatitis C, and ALT testing was unable to detect any donors who later seroconverted, as detected by HCV 2.0.     

Absence of hepatitis B virus DNA detected by polymerase chain reaction in blood donors who are hepatitis B surface antigen negative and antibody to hepatitis B core antigen positive from a United States population with a low prevalence of hepatitis B serologic markers

A recent study in hepatitis B surface antigen (HBsAg)-negative, antibody to hepatitis B core antigen (anti-HBc)-positive blood donors from a population with a high prevalence of hepatitis B serologic markers showed the presence of hepatitis B virus DNA (HBV DNA) as detected by polymerase chain reaction (PCR) in 4 percent of these donors. A sensitive, nested PCR assay was used to assess the prevalence of HBV DNA in a population of HBsAg-negative, anti-HBc-positive blood donors from a United States population with a low prevalence of hepatitis B serologic markers. The lower limit for detection by the PCR assay was 10(-5) pg per mL of HBV DNA. There was a review of 26,492 consecutive blood donations in a 12-month period. During this time, only 1 unit (0.004%) was HBsAg positive. An additional 158 units (0.6%) were repeatably reactive for anti-HBc. These 158 HBsAg-negative, anti- HBc-positive units were given by 119 donors of blood for allogeneic and autologous use. HBV DNA was not detected by PCR in blood from 83 allogeneic blood donors (93 samples) or 36 autologous blood donors (65 samples). Anti-HBc testing is an inefficient means of screening for potential hepatitis B infectivity and is associated with low test specificity in populations with a low prevalence of hepatitis B serologic markers.     

血液病患者输血与庚型肝炎病毒感染的研究

目的：了解血液病患者输血后的庚型肝炎病毒（ＨＧＶ）感染情况。方法：对６３例血液病患者采用ＲＴＰＣＲ方法检测ＨＧＶＲＮＡ、丙型肝炎病毒（ＨＣＶ）ＲＮＡ，应用ＥＬＩＳＡ方法检测抗ＨＧＶ、ＨＢｓＡｇ。结果：ＨＧＶＲＮＡ阳性率为７．９％，抗ＨＧＶ阳性率６．３％；ＨＣＶＲＮＡ阳性率为４６．０％。ＨＧＶ感染通常伴有ＨＣＶ感染及丙氨酸转氨酶升高。ＨＧＶ感染与输血量有关，与血液病种类无关。结论：血液病输血可引起ＨＣＶ、ＨＧＶ的传播     

Impact of screening blood donors for hepatitis C antibody on posttransfusion hepatitis: a prospective study with a second-generation anti-hepatitis C virus assay

BACKGROUND: Hepatitis C is the major cause of posttransfusion hepatitis. Blood components that are positive for antibody to hepatitis C virus (anti-HCV) can transmit posttransfusion hepatitis. STUDY DESIGN AND METHODS: To investigate the effect on posttransfusion hepatitis of screening blood donors with a second-generation test for anti-HCV, 249 transfusion recipients who underwent cardiovascular surgery were prospectively followed. Six recipients who were positive for anti-HCV before transfusion and 51 subjects with incomplete follow-up were excluded from this study. RESULTS: Eleven (13.8%) of 80 subjects who received unscreened blood had two successive serum alanine aminotransferase levels > 90 U per L. Seven (8.8% of total) developed anti-HCV and HCV RNA and two (2.5% of total) developed IgM antibody to cytomegalovirus (IgM anti-CMV). By contrast, 3 (2.7%) of the 112 subjects who received anti-HCV-screened blood had two successive serum alanine aminotransferase levels > 90 U per L. None of these three developed anti-HCV and HCV RNA, but two (1.8% of total) showed the development of IgM anti-CMV. The study shows that screening for anti- HCV in blood donors with a second-generation test almost abrogated posttransfusion viral hepatitis C. CONCLUSION: After anti-HCV screening, other body fluid-transmitted viruses such as CMV may become important in posttransfusion hepatitis.     

The use of polymerase chain reaction in plasma pools for the concomitant detection of hepatitis C virus and HIV type 1 RNA

BACKGROUND: Detection of viral nucleic acids might increase blood transfusion safety through the detection of recently infected blood donors during the preseroconversion window period. Individual screening is difficult to apply, because of technical and financial constraints. STUDY DESIGN AND METHODS: A polymerase chain reaction (PCR)-based assay including a polyethylene glycol precipitation step was developed for the concomitant detection of hepatitis C virus (HCV) and HIV type 1 (HIV-1) RNA in plasma pools corresponding to 50 blood donations by the use of commercial assays. RESULTS: The assay had a sensitivity of less than 33 copies per mL for HCV RNA and 1000 copies per mL for HIV-1 RNA for each individual sample included in the pool. The eight preseroconversion samples with HCV RNA between 1,250 and 762,000 copies per mL were all detected when 100-microL aliquots from the samples were introduced into 5-mL pools of 50 blood donations. CONCLUSIONS: A PCR- based pooling assay associating a prepurification step with polyethylene glycol allows for the screening of blood donations for HCV and HIV-1 RNA without marked loss of sensitivity from that seen with commercially available assays. This procedure might increase blood safety through systematic screening of blood donations at relatively low cost.     

Prevalence and trends of human immunodeficiency virus, hepatitis B virus, and hepatitis C virus among blood donors in Iran, 2004 through 2007

BACKGROUND: Evaluation and monitoring the prevalence of transfusion-transmissible viral infections in blood donors is a valuable index of donor selection and blood safety. This study analyzed the trends of blood-borne infections among Iranian blood donations during 4 years.
STUDY DESIGN AND METHODS: Viral screening results of 6,499,851 allogeneic donations from 2004 through 2007 were analyzed. All donations were screened for hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), and syphilis. The prevalence of HBV, HCV, and HIV infections per 100,000 donations and 95% confidence interval was calculated. The p value was estimated by chi-square test.
RESULTS: The prevalences of HBV, HCV, and HIV decreased during the 4-year study from 2004 through 2007. The overall prevalence was 0.56% for HBV, 0.004% for HIV, and 0.13% for HCV. There was a significant and impressive decrease in hepatitis B surface antigen prevalence from 0.73% in 2004 to 0.41% in 2007. The prevalence of HIV appeared to have decreased from 0.005% in 2004 to 0.004% in 2007 although the decrease was not significant. HCV prevalence showed a slight decline in blood donations from 0.14% in 2005 to 0.12% in 2007.
CONCLUSION: The trends of transfusion-transmitted infection prevalence in Iranian blood donations suggest that most of the safety measures employed in recent years in Iran have been effective.     

Neopterin levels during the early phase of human immunodeficiency virus, hepatitis C virus, or hepatitis B virus infection

BACKGROUND: A study was conducted to assess the diagnostic sensitivity of neopterin screening of blood donors with regard to the detection of window-phase specimens of human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV) infection. STUDY DESIGN AND METHODS: In total, 1002 diagnostic window-phase specimens from 98 seroconversion panels (29 HIV-1, 52 HCV, and 17 HBV) were analyzed with viral antigen detection, viral nucleic acid amplification testing (NAT), and neopterin quantitation assays. The study was completed by the analysis of 92 anti-hepatitis B core antigen (HBc)-reactive and 103 alanine aminotransferase (ALT)-elevated blood donor specimens. RESULTS: A significant association between elevated neopterin concentrations and the very early phase of HIV-1 infection was found. No significant correlation could be observed between neopterin levels and the early phase of HCV or HBV infection. Neopterin concentration was not increased in specimens from blood donors with anti-HBc reactivity or ALT elevation. CONCLUSIONS: Neopterin screening of blood donors may identify window-phase cases of HIV, but not of HCV or HBV infection. The diagnostic sensitivity of neopterin screening during the HIV window phase is similar to that of the p24 antigen test. With the introduction of viral NATs in blood screening, there is no additional benefit of neopterin screening with regard to the three blood-borne viruses HIV, HCV, and HBV. Acute phases of other infectious agents, however, have been reported to be detected by neopterin enzyme-linked immunosorbent assays.     

Two HBV DNA+/HBsAg− blood donors identified by HBV NAT in Shenzhen, China

Background

In order to further improve blood safety, mini-pool (MP) nucleic acid testing (NAT) was implemented to screen samples negative for hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (anti-HCV), anti-human immunodeficiency virus (anti-HIV), syphilis (anti-Treponemal antibody) and with normal ALT.

Study design and methods

From August 2006 to February 2008, 41,301 donations were screened using commercial HIV/HCV RNA and HBV DNA Real-Time PCR NAT assays in pools of 8. Reactive pools were re-tested as individual samples using the appropriate screening test and confirmed using an alternate commercial NAT assay. Donors reactive on both NAT assays were considered ‘confirmed’ positive for the virus concerned and recalled for additional follow-up testing and counseling.

Results

Of the 41,301 samples screened, no HIV or HCV RNA-positive/seronegative donations were detected but two HBV DNA positive/HBsAg negative blood donors (Donors 1 and 2) were identified. Their respective hepatitis immunological markers were: Donor 1 - anti-HBc positive/anti-HBe positive/HBeAg negative/ALT normal and HBV DNA viral load of 112 IU/ml; Donor 2 - anti-HBc positive/anti-HBe negative/HBeAg negative/ALT normal and HBV DNA viral load 2750 IU/ml.

Conclusions

MP NAT identified two HBsAg negative donors with presumed occult infection but no HIV or HCV seronegative/NAT positive (yield) donors. The HBV yield rate of 1 in 20,650 (95%CI - 1 in 5663 to 1 in 75,303) is comparatively high, exceeds the predicted rate based on previous modeling for the population and demonstrates the incremental blood safety value of NAT in countries where HBV is highly epidemic. The low viral load of the two yield samples underscores the importance of optimizing the sensitivity of the HBV NAT assay selected for screening.     

Residual risk of transfusion-transmitted human immunodeficiency virus, hepatitis C virus, and hepatitis B virus infections in Italy

BACKGROUND: Estimating the risk of transfusion-transmitted infections (TTIs) is essential for monitoring blood safety. The residual risk of TTI was estimated for nearly 90 percent of the blood supply in Italy. STUDY DESIGN AND METHODS: Data were analyzed from 1,079,281 repeat donors, corresponding to 5,361,000 donations made in blood transfusion centers throughout Italy in the period 1999 through 2001. The residual risk of transfusion-transmitted human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus (HBV) infections was estimated with the incidence rate-window period model. The denominator for the incidence rate (i.e., the number of person-years at risk) was estimated on a sample of 5850 donors. RESULTS: The risk of an infectious donation entering the blood supply, per 1 million donations, was 1.91 (probable range, 0.52-3.32) for HIV, 16.74 (9.57-24.01) for HCV, and 69.16 (43.12-102.70) for total HBV (adjusted for vaccination and hepatitis B surface antigen transience). CONCLUSION: In Italy, the estimated residual risk of TTI is apparently low, particularly for HIV infection. Although the estimated risks are higher for HCV and HBV, the introduction of mandatory viral detection tests for HCV in 2002 should account for an 80 percent reduction in the HCV risk. Moreover, the ongoing HBV vaccination program will contribute to reducing the risk of transfusion-transmitted HBV.     

Predonation screening of blood donors with rapid tests: implementation and efficacy of a novel approach to blood safety in resource-poor settings

BACKGROUND: In sub-Saharan Africa, the percentage of screened blood is limited to approximately 75 percent for human immunodeficiency virus antibodies (anti-HIV), 50 percent for hepatitis B surface antigen, and 19 percent for hepatitis C virus antibodies (anti-HCV), mainly because of costs. STUDY DESIGN AND METHODS: In 2002 to 2003, candidate blood donors were screened before donation for HIV, HCV, and hepatitis B virus (HBV) serologic markers with rapid tests. The efficacy of this screening was assessed by nucleic acid testing (NAT) applied to pools of 10 plasma samples from donated units with a virus specific triplex assay. NAT-reactive pools were resolved by viral genome identification in individual plasma sample. Deferred candidate donors were referred to a donor-care program. RESULTS: A total of 9372 people were screened and 1534 (16.4%) were deferred. No HIV or HCV RNA-containing samples remained undetected by rapid tests unless a human testing error was involved. In contrast, 1.3 and 3.0 percent of HBV DNA-containing blood units were negative with rapid tests but were detected in individual donations with enzyme immunoassay and genomic amplification, respectively. Only half of these units were detectable in pools of 10 samples. One-third of deferred candidate donors attended the donor-care program and were informed and counseled. CONCLUSIONS: Predonation viral screening of blood donors is effective in high endemic areas, and the savings it generates may improve the safety and limit the cost of blood. Communication with deferred donors may contribute to public health. A new screening strategy associating serologic rapid test before donation and NAT on pools of 10 plasma samples after donation is proposed.     

Correlates of hepatitis C virus (HCV) RNA negativity among HCV-seropositive blood donors

BACKGROUND: Approximately 20 percent of persons infected with hepatitis C virus (HCV) clear viremia. Factors associated with resolution of viremia are not well defined. Implementation of routine nucleic acid testing (NAT) of blood donors has yielded a large data set for analysis of demographic correlates of resolved viremia. STUDY DESIGN AND METHODS: HCV antibody and NAT data, liver enzyme (alanine aminotransferase [ALT]) results, and donor demographic characteristics were compiled for 2,579,290 allogeneic donations given at five large blood centers after NAT implementation in 1999 through December 2001. Donation HCV RNA status was compared between first-time donors categorized by ALT levels, sex, age, race and/or ethnicity, country of birth, level of education, blood center location, and blood group, with chi-square tests and multivariable logistic regression methods. RESULTS: Of 35 confirmed-seropositive repeat donors, 19 (54.3%) tested negative for the presence of HCV RNA; there was no association between RNA status and preseroconversion intervals (p = 0.74). Of 2105 RIBA-positive, first-time donors, 402 (19.1%) tested negative for the presence of HCV RNA by NAT (presumptive resolved infections). There were significant differences in the frequency of RNA negativity among first-time donors categorized by ALT levels and by race and/or ethnicity. ALT levels were more likely to be elevated in RNA-positive, first-time donors (p < 0.0001). Viremia was less likely to resolve in Asian (8.2%) and black non-Hispanic (14.4%) donors than in white non-Hispanic (20.7%), Hispanic (22.1%), and other race and/or ethnicity (22.1%) donors (p = 0.02). No significant associations were found for age, sex, country of origin, level of education, blood type, and donor center location. CONCLUSION: These results confirm that the frequency of HCV RNA negativity among seropositive persons differs by race and/or ethnicity. Follow-up studies of donors with resolved viremia are warranted to further elucidate viral, immunologic, and genetic factors underlying spontaneous viral clearance.