APH-2 and Tax expression are correlated with a HTLV-2 proviral load but not with lymphocytosis

International audiencen.

Proficiency Testing of Viral Marker Screening in African Blood Centers - Seven African Countries, 2017.

A 2014 report evaluating accuracy of serologic testing for transfusion-transmissible viruses at African blood center laboratories found sensitivities of 92%, 87%, and 90% for detecting infections with human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV), respectively (1). Following substantial investments in national blood transfusion service (NBTS) laboratories, in 2017 investigators tested proficiency at 84 blood center laboratories (29 NBTS and 55 non-NBTS) in seven African countries. A blinded panel of 25 plasma samples was shipped to each participating laboratory for testing with their usual protocols based on rapid diagnostic tests (RDTs) (2) and third and fourth generation enzyme immunoassays (EIA-3 and EIA-4). Sensitivity and specificity were estimated using separate regression models that clustered assays by laboratory and adjusted for assay type and NBTS laboratory status. Mean specificities were ≥95% for all three viruses; however, mean sensitivities were 97% for HIV-positive, 76% for HBV-positive, and 80% for HCV-positive samples. Testing sensitivities for all viruses were high when EIA-3 assays were used (≥97%). Lower sensitivities for HBV-positive samples and HCV-positive samples were associated with assay types other than EIA-3, used primarily by non-NBTS laboratories. Proficiency for HIV testing has improved following international investments, but proficiency remains suboptimal for HBV and HCV testing. In sub-Saharan African blood centers, the quality of rapid tests used for HBV and HCV screening needs to be improved or their use discouraged in favor of EIA-3 tests

Seroprevalence of Human T-lymphotropic virus type-1 and -2 infections among first-time United States Blood Donors 2000-2009

Background: Human T-lymphotropic virus types 1 and 2 (HTLV-1 and –2) are prevalent at low-level among United States blood donors, but recent data on their prevalence is lacking. Methods: Data on all first-time blood donors in a large network of United States blood centers was examined during the period 2000-2009. Anti-HTLV-1 and -2 was measured by enzyme immunoassay (EIA) screening with type-specific confirmation by immunofluorescence or RIBA. Prevalence and odds ratios (OR) and 95% confidence intervals (CI) for associations with demographic characteristics were assessed using multivariable logistic regression. Results: Among 2,047,740 first-time donors, 104 donors were seropositive for HTLV-I (prevalence 5.1 (95% CI: 4.1 - 6.1) per 100,000) and 300 donors were seropositive for HTLV-2 infection (prevalence 14.7 (95% CI 13.0 - 16.3) per 100,000). Prevalence was lower than reported in the 1990’s but stable from 2000 to 2009. HTLV-1 seropositivity was associated with female sex (OR = 1.56, 95% CI 1.05-2.32); older age; and Black (IR = 25.29, 9% CI 13.14- 48.68) and Asian (OR = 21.43, 95% CI 10.31-44.53) race/ethnicity. HTLV-2 seropositivity was associated with female sex (OR = 2.13, 95% CI 1.67-2.73); older age; and non-white race/ethnicity; residence in the Western (OR=4.12, 95% CI 2.16-7.82) and Southwestern (OR=2.47, 95% CI 1.28-4.78; both vs. Northern) U.S.; and lower educational level. Conclusions: HTLV-1 and -2 prevalences among U.S. blood donors declined since the early 1990’s but were stable since 2000. Higher prevalence of HTLV-2 in the West and Southwest may be attributed to endemic foci among Amerindians

Association between HLA Class I and Class II Alleles and the Outcome of West Nile Virus Infection: An Exploratory Study

BACKGROUND: West Nile virus (WNV) infection is asymptomatic in most individuals, with a minority developing symptoms ranging from WNV fever to serious neuroinvasive disease. This study investigated the impact of host HLA on the outcome of WNV disease. METHODS: A cohort of 210 non-Hispanic mostly white WNV(+) subjects from Canada and the U.S. were typed for HLA-A, B, C, DP, DQ, and DR. The study subjects were divided into three WNV infection outcome groups: asymptomatic (AS), symptomatic (S), and neuroinvasive disease (ND). Allele frequency distribution was compared pair-wise between the AS, S, and ND groups using χ2 and Fisher's exact tests and P values were corrected for multiple comparisons (Pc). Allele frequencies were compared between the groups and the North American population (NA) used as a control group. Logistic regression analysis was used to evaluate the potential synergistic effect of age and HLA allele phenotype on disease outcome. RESULTS: The alleles HLA-A*68, C*08 and DQB*05 were more frequently associated with severe outcomes (ND vs. AS, P(A*68) = 0.013/Pc = 0.26, P(C*08) = 0.0075/Pc = 0.064, and P(DQB1*05) = 0.029/Pc = 0.68), However the apparent DQB1*05 association was driven by age. The alleles HLA-B*40 and C*03 were more frequently associated with asymptomatic outcome (AS vs. S, P(B*40) = 0.021/Pc = 0.58 and AS vs. ND P(C*03) = 0.039/Pc = 0.64) and their frequencies were lower within WNV(+) subjects with neuroinvasive disease than within the North American population (NA vs. S, P(B*40) = 0.029 and NA vs. ND, P(C*03) = 0.032). CONCLUSIONS: Host HLA may be associated with the outcome of WNV disease; HLA-A*68 and C*08 might function as "susceptible" alleles, whereas HLA-B*40 and C*03 might function as "protective" alleles

Determinants of subject visit participation in a prospective cohort study of HTLV infection

<p>Abstract</p> <p>Background</p> <p>Understanding participation in a prospective study is crucial to maintaining and improving retention rates. In 1990–92, following attempted blood donation at five blood centers, we enrolled 155 HTLV-I, 387 HTLV-II and 799 HTLV seronegative persons in a long-term prospective cohort.</p> <p>Methods</p> <p>Health questionnaires and physical exams were administered at enrollment and 2-year intervals through 2004. To examine factors influencing attendance at study visits of the cohort participants we calculated odds ratios (ORs) with generalized estimated equations (GEE) to analyze fixed and time-varying predictors of study visit participation.</p> <p>Results</p> <p>There were significant independent associations between better visit attendance and female gender (OR = 1.31), graduate education (OR = 1.86) and income > $75,000 (OR = 2.68). Participants at two centers (OR = 0.47, 0.67) and of Black race/ethnicity (OR = 0.61) were less likely to continue. Higher subject reimbursement for interview was associated with better visit attendance (OR = 1.84 for$25 vs. $10). None of the health related variables (HTLV status, perceived health status and referral to specialty diagnostic exam for potential adverse health outcomes) significantly affected participation after controlling for demographic variables.</p> <p>Conclusion</p> <p>Increasing and maintaining participation by minority and lower socioeconomic status participants is an ongoing challenge in the study of chronic disease outcomes. Future studies should include methods to evaluate attrition and retention, in addition to primary study outcomes, including qualitative analysis of reasons for participation or withdrawal.</p

Implementation of a script for predonation interviews: impact on human immunodeficiency virus risk in South African blood donors

BACKGROUND: The way in which the donor history questionnaire is conducted plays a crucial role in the self-disclosure of behavioral risk factors for human immunodeficiency virus (HIV) infection by prospective donors. The South African National Blood Service changed its policy on the process of donor assessment in May 2015 by implementing a compulsory interviewer script used to assess donor eligibility. STUDY DESIGN AND METHODS: A pre- and postevaluation study to determine the impact of scripted interviews on high-risk deferrals and recently acquired HIV infections. We used historical data to compare 18 months before and after the implementation of the script. RESULTS: We recorded a total of 3,169,656 donor presentations during the two 18-months periods, of which 52.2% (1,655,352) were made during the scripted period. A multivariable logistic regression analysis adjusting for donor and demographic characteristics found the odds of high-risk deferral to be slightly greater (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.05-1.07) during the scripted period. A separate multivariate logistic regression model, also adjusting for donor and demographic characteristics, showed that the odds of recently acquired HIV infection were significantly lower (OR, 0.88; 95% CI, 0.79-0.97) during the scripted period. CONCLUSION: This study showed that implementation of a scripted interview was associated with increased HIV risk deferral and decreased recent HIV infection. This study indicates potential improvement in blood safety with the implementation of a scripted donor interview and has relevance to blood safety in other sub-Saharan African countries

Blood group A and D negativity are associated with symptomatic West Nile virus infection.

BACKGROUND: West Nile virus (WNV) infection is mostly asymptomatic (AS) but 20% of subjects report WNV fever and 1% of patients experience neurologic diseases with higher rates in elderly and immunosuppressed persons. With no treatment and no vaccine to prevent the development of symptomatic (S) infections, it is essential to understand prognostic factors influencing S disease outcome. Host genetic background has been linked to the development of WNV neuroinvasive disease. This study investigates the association between the ABO and D blood group status and WNV disease outcome. STUDY DESIGN AND METHODS: The distribution of blood groups was investigated within a cohort of 374 WNV+ blood donors including 244 AS and 130 S WNV+ blood donors. Logistic regression analyses were used to examine associations between A, B, O, and D blood groups and WNV clinical disease outcome. RESULTS: S WNV+ donors exhibited increased frequencies of blood group A (S 47.6%, AS 36.8%, p = 0.04; odds ratio [OR], 1.56; 95% confidence interval [CI], 1.01-2.40) and D- individuals (S 21.5%, AS 13.1%, p = 0.03; OR, 1.82; 95% CI, 1.04-3.18). CONCLUSION: The findings suggest a genetic susceptibility placing blood group A and D- individuals at risk for the development of S disease outcome after WNV infection

Demographic determinants of syphilis seroprevalence among U.S. blood donors, 2011-2012.

BackgroundNo cases of transfusion-transmitted syphilis have been described for over four decades. While there is mandatory transfusion screening for syphilis, the absence of transmission is in part ascribed to a low prevalence of syphilis in the blood donor population, the concomitant use of antibiotics in a high proportion of transfusion recipients, allied with poor survival of T. pallidum during refrigerated storage of blood products.MethodsA cross-sectional retrospective data analysis was conducted to ascertain the prevalence of Treponema pallidum antibodies in U.S. blood donors by demography and geography. Routine blood donation testing data and demographics were extracted from the data warehouse of a large network of U.S. blood centers. Crude and adjusted prevalence of T. pallidum antibodies and active syphilis infection were calculated, and GIS mapping was used to illustrate geographic distribution.ResultsThe prevalence of T. pallidum seropositivity and active syphilis in first time donors was 162.6 (95% CI 145.5-181.2) per 100,000 donors and 15.8 (95% CI 10.8-22.3) per 100,000 donors, respectively. The odds of T. pallidum seropositivity were significantly elevated in African American (OR = 18.9, 95% CI 14.2-25.2), and Hispanic (OR = 2.8, 95% CI 2.0-3.8) as compared to Caucasian donors. Similarly, the odds of active T. pallidum infections were significantly higher in African American (OR 15.0, 95% CI 7.0-32.3) and Hispanic (OR = 5.8, 95% CI 2.9-11.6) as compared to Caucasian donors. Syphilis seropositivity was associated with first time blood donation, increasing age, lower education, birth outside the US, and positive tests for HIV and HCV. Geographically, T. pallidum seropositivity was increased in southern and western regions of the US.ConclusionsGiven the low seroprevalence of syphilis in blood donors, continued screening remains debatable; however it may provide a public health benefit through surveillance of at-risk populations