Current value of serologic test for syphilis as a surrogate marker for blood-borne viral infections among blood donors in the United States

BACKGROUND: Serologic screening for syphilis has been justified in part as a surrogate marker for infections caused by other pathogens such as human immunodeficiency virus (HIV). This study assessed the current surrogate value of the test.
STUDY DESIGN AND METHODS: Testing results for blood donors with the American Red Cross Blood Services between January 1, 2006, and December 31, 2007, were analyzed. All donations were tested according to standard procedures for markers of HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), human T-lymphotropic virus (HTLV), syphilis, and other infections. The frequency of window-period (w-p) infections interdicted by syphilis testing was estimated.
RESULTS: There were significantly higher frequencies of HIV, HCV, hepatitis B surface antigen (HBsAg), and HTLV confirmed-positive donations among those with positive syphilis test results, although the sensitivity of syphilis test positivity in these groups was low. Among more than 3 million repeat donors with complete testing through reactive donation confirmation for both syphilis and HIV (anti-HIV and HIV RNA), 225 seroconverted for syphilis but not for anti-HIV or HIV RNA and 83 converted for HIV (anti-HIV or HIV RNA) but not for syphilis, with only 1 who converted for both syphilis and HIV, resulting in an incidence ratio of 150 (95% confidence interval, 21-1080) and a sensitivity of 1.2 percent. No syphilis seroconverters converted for HCV, HBsAg, or anti-HTLV.
CONCLUSION: Syphilis testing presents no surrogate value for incident HCV, HBV, and HTLV infections and could only remove approximately 1 HIV w-p unit of every 148 million donations.     

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.     

A comparison of human immunodeficiency virus,hepatitis C virus,hepatitis B virus,and human T‐lymphotropic virus marker rates for directed versus volunteer blood donations to the American Red Cross during 2005 to 2010

BACKGROUND: At most US blood centers, patients may still opt to choose specific donors to give blood for their anticipated transfusion needs. However, there is little evidence of improved safety with directed donation when compared to volunteer donation. STUDY DESIGN AND METHODS: The percentage of directed donations made to the American Red Cross (ARC) from 1995 to 2010 was determined. Infectious disease marker rates for human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV), and human T‐lymphotropic virus (HTLV) were calculated for volunteer and directed donations made from 2005 to 2010. Odds ratios (ORs) were calculated to compare marker‐positive rates of directed donations to volunteer donations. RESULTS: The percentage of donations from directed donors declined from 1.6% in 1995 to 0.12% in 2010. From 2005 to 2010, the ARC collected 38,894,782 volunteer and 69,869 directed donations. Rates of HIV, HCV, HBV, and HTLV for volunteer donations were 2.9, 32.2, 12.4, and 2.5 per 100,000 donations, respectively; for directed, the rates were 7.2, 93.0, 40.1, and 18.6 per 100,000. After demographics and first‐time or repeat status were adjusted for, corresponding ORs of viral marker positivity in directed versus volunteer donations were not significant for HIV, HBV, or HTLV and significant for HCV (OR, 0.7; 95% confidence interval, 0.50‐0.90). CONCLUSIONS: Directed donations have declined by 92% at the ARC since 1995, but have higher viral marker rates than volunteer donations. The difference can be explained in part by the effects of first‐time or repeat status of the donors. Patients considering directed donation should be appropriately counseled about the potential risks.     

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.     

Prevalence,incidence, and residual risk of major blood‐borne infections among apheresis collections to the American Red Cross Blood Services, 2004 through 2008

BACKGROUND: The number of apheresis collections increased significantly in recent years; however, data on viral marker rates among these collections are lacking. STUDY DESIGN AND METHODS: Apheresis collection data for 2004 to 2008 were analyzed. All collections were tested for antibodies and viral RNA for human immunodeficiency virus (HIV) and hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti‐HBc), antibody to human T‐lymphotropic virus (anti‐HTLV), and other markers. HBsAg‐confirmed‐positive but anti‐HBc–nonreactive units were further verified by HBV DNA testing. RESULTS: From 2004 to 2008, apheresis collections for double red blood cells (R2) increased by 294% to a total of 37% of all apheresis collections. Marker rates (/100,000) among all apheresis collections were 1.41, 7.83, 2.04, and 0.28, for HIV, HCV, HBsAg, and HTLV. Among R2 collections, rates (/100,000) were 6‐ to 13‐fold higher than among non‐R2 collections for HIV (3.50 vs. 0.53), HCV (21.84 vs. 1.96), and HBsAg (5.83 vs. 0.44), but not HTLV (0.53 vs. 018). First‐time male R2 donors accounted for 25% to 100% of positivity but only 1% to 5% of the total number of apheresis collections. Incidence (/100,000 person‐years) and residual risk estimates among repeat apheresis donors between 2007 and 2008 for HIV were 3.82 and 1:1.0 million, for HCV were 1.53 and 1:3.2 million, and for HBsAg were 4.85 and 1:200,000. These estimates were comparable to those among repeat whole blood donors. CONCLUSION: The risk of major blood‐borne infections among current apheresis collections was low; however, an upward trend in the viral marker frequency among apheresis donations was attributable to the contribution of first‐time, male R2 donors.     

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.     

Surveillance of risk profiles among new and repeat blood donors with transfusion-transmissible infections from 1995 through 2003 in the Netherlands

BACKGROUND: To evaluate the effectiveness of blood donor selection, this study reports risk profiles of donors with transfusion-transmissible infections as obtained by ongoing surveillance, 1995 through 2003, in the Netherlands. STUDY DESIGN AND METHODS: A surveillance program was installed to monitor risk profiles among new and repeat donors infected with human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV), or human T-lymphotropic virus (HTLV), or positive for the presence of syphilis antibodies. At posttest counseling, a physician interviewed donors to clarify possible sources of infection. RESULTS: A total of 167 repeat donors and 404 new donors were interviewed: 33 with HIV, 123 with HCV, 279 with HBV, 21 with HTLV, and 112 with syphilis antibodies. Most HBV, HCV, and HTLV infections were among new donors (80, 85, and 67%), whereas most HIV infections were among repeat donors (79%). Nearly 25 percent of the donors did not report factors at screening that would have deferred them from donating blood. At posttest interviews, new donors with HCV often reported injecting drug use (19%). Repeat donors with HIV often reported male-to-male sex (8/26, 31%). CONCLUSION: A significant level of deferrable behavioral risks was found among donors with confirmed transfusion-transmissible infections that persist despite current donor selection. Reporting such behavior at initial donor selection would have eliminated a substantial part of the infections found. This study argues against relaxing the existing donor deferral of persons practicing male-to-male sex, given their significant proportion of HIV infections among repeat donors. Systematic surveillance of risk factors among infected blood donors provides ongoing information about the effectivity of donor selection and is recommended to evaluate and optimize blood policies.     

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.     

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.     

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.     

Patterns of age- and sex-specific prevalence of major blood-borne infections in United States blood donors, 1995 to 2002: American Red Cross blood donor study

BACKGROUND: The American Red Cross has been maintaining a research database of all blood donations, including all testing results for infectious disease markers, since 1995. This study analyzes the temporal trends of major blood-borne infections among blood donors. STUDY DESIGN AND METHODS: Temporal trends for age- and sex-specific prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), and syphilis infections in US blood donors were analyzed based on linear trend or time series model or other models as appropriate. RESULTS: From 1995 to 2002, significant declines have been observed for infections that used to be at relatively higher levels. Declines in prevalence were slower among first-time donations than repeat donations. There was an increase in prevalence of anti-HCV among first-time male donors of 50 to 59 years of age. Anti-HIV prevalence appeared to have increased among first-time male donors of 30 to 39 years of age since 2000. CONCLUSION: Different sex and age groups showed various patterns of decline and even signs of increase. The increasing prevalence among some age and sex groups may merit further investigation.     

Two cases of transfusion‐transmitted hepatitis B virus (HBV) infection in a low‐endemic country before implementation of HBV nucleic acid testing

BACKGROUND: The risk of hepatitis B virus (HBV) transmission by transfusion is higher than that of other blood‐borne viruses. In France, before the introduction of HBV nucleic acid testing (NAT) in 2010, blood donations were tested for hepatitis B surface antigen (HBsAg) and antibodies against hepatitis B core antigen, and the residual risk of HBV transfusion related to preseroconversion acute phase was estimated at 0.54 per million donations. The additional value of the implementation of a highly sensitive HBV NAT to prevent such transmissions is discussed. STUDY DESIGN AND METHODS: Two lookback investigations based on HBV seroconversion of repeat donors were performed. Donors and recipients were followed up in multiple samples that were tested for HBV serologic and molecular markers. RESULTS: The recipients have shown posttransfusion HBsAg seroconversion. The archived samples from the implicated donations were positive for HBV DNA at extremely low viral load in both cases. HBV isolates from donors and recipients of each case were organized in the same cluster with 100% identities into Genotypes A2 and B4, respectively. One recipient spontaneously recovered from infection while the second was successfully treated. CONCLUSION: The present cases highlight the importance of introducing highly sensitive HBV NAT to prevent transmission. Moreover, the lookback studies based on appropriate molecular and serologic investigations of patients transfused with previous donations from newly identified HBV‐infected repeat donors offer the opportunity to treat a recently infected recipient.     

Predictive value of past and current screening tests for syphilis in blood donors: changing from a rapid plasma reagin test to an automated specific treponemal test for screening

BACKGROUND: This study evaluated the change from a rapid plasma reagin (RPR) test to an automated specific treponemal test (PK-TP) in screening for syphilis in blood donors. STUDY DESIGN AND METHODS: A cross-sectional seroprevalence analysis was performed on 4,878,215 allogeneic blood donations from 19 American Red Cross Blood Services regions from May 1993 through September 1995. Positive predictive values relative to the confirmatory fluorescent treponemal antibody absorption test (FTA-ABS) were calculated. Differences in seroprevalence were compared in RPR and PK-TP tests for 1) unconfirmed and confirmed tests, 2) first-time and repeat donors, and 3) "recent" versus "past" infections. Donation data from three additional Red Cross regions were evaluated for repeat donation patterns of blood donors who had a donation that was positive in a serologic screening test for syphilis. The value of RPR and PK-TP tests as surrogate markers for HIV infection was compared. RESULTS: Reactive rates were lower but the positive predictive values was higher for the PK-TP test than for the RPR test. Initially, donors screened by PK-TP were more likely to be confirmed as positive than were donors screened by RPR, but these rates became comparable. It is estimated that a single HIV window-period donation was removed by serologic testing for syphilis each year of this study period. CONCLUSIONS: The change to the PK-TP test resulted in a lower repeatedly reactive rate, better prediction that a confirmed-positive test for syphilis would occur in testing in the FTA-ABS, fewer donations lost, and comparable deferral rates. Because of the high rate of reactivity to serologic testing for syphilis among donors previously confirmed positive for syphilis, indefinite deferral after a confirmed-positive index donation may be warranted. Serologic testing for syphilis is ineffective as a marker of HIV-infectious window-period donations.     

Limited effectiveness of donor deferral registries for transfusion-transmitted disease markers

BACKGROUND: Donor deferral registries (DDRs) detect repeat donations by previously deferred donors and prevent their release. The utility of DDRs has not been objectively demonstrated. STUDY DESIGN AND METHODS: A total of 10.2 million first-time donors to the American Red Cross from 1995 through 2002 were reviewed to identify donors deferred by screening tests for human immunodeficiency virus (HIV; 0.19% of donors), hepatitis C virus (HCV; 0.55%), and hepatitis B virus (HBV; 0.13%). All repeat-reactive (RR) donors were deferred despite confirmatory testing. Donors were notified and counseled about their test results and deferral. Their subsequent donation behavior was assessed. RESULTS: A total of 414 HIV-deferred donors (2.1%), 471 HCV-deferred donors (0.8%, p < 0.001 vs. HIV and HBV), and 222 HBV-deferred donors (1.6%, p < 0.01 vs. HIV) returned to donate despite their deferred status. For all three tests, confirmed-positive donors were less likely to return. Of donors originally confirmed positive, only 7 returning donors were negative by screening (thus the repeat donation interdicted from distribution by the DDR): 0 HIV RR donors, 2 of 36,092 HCV RR donors, and 5 of 8,404 HBV RR donors. Review of the laboratory results for the HCV donors and one HBV donor was consistent with originally false-positive confirmation tests. The four other HBV confirmed-positive donors were anti-hepatitis B core antigen-positive on their subsequent donation, which was discarded despite the DDR. CONCLUSION: Of 10.2 million donors, the DDR did not prevent the release of any potentially dangerous blood component due to inappropriate return of donors deferred for HIV, HCV, and HBV tests. The effectiveness of DDRs should be evaluated for other deferrals.     

Does prevalence of transfusion‐transmissible viral infection reflect corresponding incidence in United States blood donors?

BACKGROUND: Calculation of viral residual risk is dependent on estimating incidence, which is not easily obtainable by most blood centers. Prevalence, however, is readily available. Understanding whether prevalence reflects corresponding incidence may help blood centers monitor disease risks. STUDY DESIGN AND METHODS: With data on 12 million allogeneic donations, prevalence and incidence of transfusion-transmitted viral infections (TTVIs) were calculated. Relationships between prevalence (in total, first-time, and repeat donations) and incidence were analyzed for human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) relative to temporal and donor demographic stratifications, respectively. RESULTS: Overall prevalence of HIV, HBV, and HCV did not consistently reflect corresponding incidence. The relationship between prevalence and incidence varied with time and donors' age and was virus-specific. CONCLUSION: Incidence of TTVIs cannot be easily predicted from overall prevalence. Accurate assessment of TTVI risk necessitates knowledge about donation histories and person-years at risk. Establishing comprehensive frameworks for monitoring blood donations and infectious disease markers remains a key to monitoring blood safety.     

Trends in prevalence,incidence, and residual risk of major transfusion‐transmissible viral infections in United Arab Emirates blood donors: impact of individual‐donation nucleic acid testing, 2004 through 2009

BACKGROUND: United Arab Emirates (UAE) has a heterogeneous population consisting of more than 160 nationalities and 85% of the population being non‐UAE. In 2007, Dubai Blood Donation Centre (DBDC), the major local supplier of blood in the UAE, introduced six‐minipool nucleic acid test (NAT) for hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV), which in 2008 upgraded to individual‐donation (ID)‐NAT. The aim of this study was to analyze the efficacy of the donor screening program in the UAE and evaluate the impact of NAT on the yield and residual risk of transfusion‐transmissible viral infections (TTVIs). STUDY DESIGN AND METHODS: A total of 169,781 blood donations collected at DBDC between 2004 and 2009 were screened for TTVIs. During the period 2008 through 2009, a total of 59,283 donations were tested with both ID‐NAT and serologic assays. The incidence, prevalence, and residual risk for each viral agent were estimated and analyzed. RESULTS: The individual prevalences of HBV, HCV, and HIV per 100,000 donation were 234.4, 110, and 4, respectively. Calculated residual risk per million donations for HBV was decreased from 1.41 in pre‐NAT period to 0.92 in post‐NAT period. These figures were decreased for HCV and HIV from 1.73 and 0.39 to 0 and 0.32, respectively. CONCLUSION: Incidence rates and estimated residual risk indicate that the current risk of TTVIs attributable to blood donation is relatively low in the UAE. The study recommends the parallel use of both serology and ID‐NAT TTVIs screening in blood donations and suggests the exclusion of antibody to hepatitis B core antigen–positive donations as this can eliminate the potential infectivity of these units with marginal effects on the blood stock in UAE.     

Serologic and molecular typing of human T‐lymphotropic virus among blood donors in Maputo City,Mozambique

BACKGROUND: Screening for human T‐lymphotropic virus‐1/2 (HTLV‐1/2) infection is not performed in blood banks in Mozambique. The aim was to determine the prevalence of HTLV‐1/2 among blood donors of the Maputo Central Hospital Blood Bank and measure the coinfection rate of HTLV‐1/2 with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and syphilis. STUDY DESIGN AND METHODS: A total of 2019 consecutive blood donors were screened for HTLV‐1/2 antibodies, HIV‐1/2 antibodies, hepatitis B surface antigen (HBsAg), and rapid plasma reagin (RPR) for syphilis. Specimens reactive on a first HTLV‐1/2 enzyme immunoassay (EIA) were retested using a second EIA. Specimens that were dually reactive on both EIAs were further tested using Western blot (WB) and real‐time polymerase chain reaction (PCR). RESULTS: All 18 dually reactive specimens (0.89%; 95% confidence interval, 0.48%‐1.30%) were positive for the presence of HTLV‐1 by WB and real‐time PCR. HTLV‐2 was not detected. The prevalences of anti‐HIV, HBsAg, and reactivity in the RPR test were 5.72, 6.01, and 0.98 percent, respectively. There was no significant association between HTLV‐1 infection and demographic variables (age and sex) or serologic markers (HIV, HBsAg, and RPR). For the 17 HTLV‐1–positive donors for whom serologic data for HIV, HBsAg, and syphilis RPR were available, 2 showed coinfection with HIV and 1 with HBV. CONCLUSION: Compared to other infectious agents, HTLV‐1 is present at relatively low levels among blood donors in Mozambique. Cost and logistics will present as major challenges for introducing HTLV‐1/2 screening in blood banks. In blood banks in Southern Africa where EIA testing is possible, a sequential algorithm of two EIAs may be a cost‐efficient option for HTLV‐1/2 screening.     

Serological findings amongst first‐time blood donors in Yaoundé, Cameroon: is safe donation a reality or a myth?

Blood safety remains an issue of major concern in transfusion medicine in developing countries where national blood transfusion services and policies, appropriate infrastructure, trained personnel and financial resources are lacking. This is aggravated by the predominance of family and replacement, rather than regular benevolent, nonremunerated donors. Thus, in order to identify and encourage healthy, regular and benevolent nonremunerated donors, consenting first-time blood donors in the Yaoundé University Teaching Hospital were screened for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBSAg), hepatitis C virus (HCV), human T-cell lymphotropic virus-I (HTLV-I) and syphilis using standard methods. Of 252 first-time donors recruited, 66 (26.2%) were positive for at least one of the infections screened. There were 7.9% positive for HIV, 10.7% for HBSAg, 4.8% for HCV and 9.1 and 1.6%, respectively, for syphilis and HTLV-I. About 30% of the 66 infected persons had co-infections. HIV-positive donors had a significantly increased risk of being positive for antibodies to syphilis (OR = 7.27; 95% CI = 2.23-23.51; P = 0.0007), not observed for HBV, HCV and HTLV-I. These results suggest that blood transfusion is still very unsafe in this community and that it is imperative that emphasis be laid on donor education. Furthermore, donors with a history of sexually transmitted infections should be totally excluded from all donations.     

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.     

Prevalence of hepatitis B virus and hepatitis C virus among blood donors at a tertiary care hospital in India: a five‐year study

BACKGROUND: Hepatitis B virus (HBV) and hepatitis C virus (HCV) are important transfusion‐transmissible infections. This study was performed to assess the prevalence of HBV and HCV seropositivity among blood donors at a tertiary care hospital–based blood bank in India. STUDY DESIGN AND METHODS: The blood donation records over 5 years (2005‐2009) were reviewed, retrospectively, for the prevalence and yearly trends of HBV and HCV seropositivity. RESULTS: A total of 94,716 donations were received. The overall number of HBV‐seropositive donations was 1353 and that for HCV was 537, with the prevalence rates of 1.43% for hepatitis B surface antigen (HBsAg) and 0.57% for HCV. The seropositivity rate was higher in the replacement donors compared to the voluntary donors. The annual rates showed decreasing trends in case of HBsAg, but in case of HCV, there was a linear increase. CONCLUSIONS: Our study raises serious concerns regarding the HBV and HCV prevalence in our country. Although HBV showed decreasing trends, it cannot be relied upon because the donors were screened only for HBsAg. HCV is clearly on the rise. Stringent measures need to be taken on urgent basis including dissemination of information, strict screening of blood, inclusion of antibody to hepatitis B core antigen and other sensitive markers to the screening protocol, and better donor recruitment.