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Baoguang Wang

Publications and source records attributed to Baoguang Wang.

6 recordsLinked to original sources

A prospective study of sexual transmission of human T lymphotropic virus (HTLV)-I and HTLV-II.

BACKGROUND: Cross-sectional studies support sexual transmission of human T lymphotropic virus (HTLV)-I/II; however, prospective incidence data, particularly for HTLV-II, are limited. METHODS: A cohort of 85 HTLV-positive (30 with HTLV-I and 55 with HTLV-II) blood donors and their stable (>or=6 months) heterosexual sex partners were followed biannually over the course of a 10-year period. RESULTS: Four of 85 initially seronegative sex partners of HTLV-I and -II carriers seroconverted, for an incidence rate (IR) of 0.6 transmissions/100 person-years (py) (95% confidence interval [CI], 0.2-1.6). This includes 2 HTLV-I transmissions/219 py (IR, 0.9 transmissions/100 py [95% CI, 0.1-3.3]) and 2 HTLV-II transmissions/411 py (IR, 0.5 transmissions/100 py [95% CI, 0.06-1.8]), with no significant difference by HTLV type. There were 2 male-to-female (IR, 1.2 transmissions/100 py [95% CI, 0.1-4.3]) and 2 female-to-male (IR, 0.4 transmissions/100 py [95% CI, 0.05-1.6) transmissions. HTLV-I or -II proviral load was 2 log10 lower in newly infected partners than in index positive partners who transmitted HTLV (P=.007). CONCLUSIONS: The incidence of sexual transmission of HTLV-II may be similar to that of HTLV-I, and female-to-male transmission may play a more important role than previously thought. HTLV-I and -II proviral load may be lower in sexually acquired infection, because of a small infectious dose.

Adult↗

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.

Blood Banks↗

Higher human T lymphotropic virus (HTLV) provirus load is associated with HTLV-I versus HTLV-II, with HTLV-II subtype A versus B, and with male sex and a history of blood transfusion.

BACKGROUND: High human T lymphotropic virus (HTLV)-I provirus load (VL) has been associated with an increased risk of HTLV-associated myelopathy, but little is known about variation in HTLV-I or -II VLs by demographic characteristics and risk behaviors. METHODS: We measured HTLV-I and HTLV-II VLs in a large cohort of 127 HTLV-I-seropositive and 328 HTLV-II-seropositive former blood donors, by use of real-time polymerase chain reaction using tax primers. Multivariable linear regression was used to control for confounding by relevant covariates. RESULTS: The mean VLs were 3.28 log(10) copies/10(6) peripheral blood mononuclear cells (PBMCs) (range, 0.5-5.3 log(10) copies/10(6) PBMCs) for HTLV-I and 2.60 log(10) copies/10(6) PBMCs (range, 0.05-5.95 log(10) copies/10(6) PBMCs) for HTLV-II (P<.0001). HTLV-II VLs were higher in those subjects with subtype A infection (mean, 2.82 log(10) copies/10(6) PBMCs) than in those with subtype B infection (mean, 2.29 log(10) copies/10(6) PBMCs) (P=.005). Higher HTLV-I VL was associated with previous receipt of a blood transfusion (P=.04), and lower HTLV-II VL was associated with female sex (P=.007). These associations persisted in virus-specific multivariate linear regression models controlling for potential confounding variables. CONCLUSIONS: VL was significantly higher in HTLV-I than in HTLV-II infection and was higher in HTLV-II subtype A than in HTLV-II subtype B infection. Chronic HTLV VLs may be related to the infectious dose acquired at the time of infection, with higher VLs following acquisition by blood transfusion and lower VLs following sexual acquisition.

Adult↗

Increased mortality associated with HTLV-II infection in blood donors: a prospective cohort study.

BACKGROUND: HTLV-I is associated with adult T-cell leukemia, and both HTLV-I and -II are associated with HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Several published reports suggest that HTLV-I may lead to decreased survival, but HTLV-II has not previously been associated with mortality. RESULTS: We examined deaths among 138 HTLV-I, 358 HTLV-II, and 759 uninfected controls enrolled in a prospective cohort study of U.S. blood donors followed biannually since 1992. Proportional hazards models yielded hazard ratios (HRs) for the association between mortality and HTLV infection, controlling for sex, race/ethnicity, age, income, educational level, blood center, smoking, injection drug use history, alcohol intake, hepatitis C status and autologous donation. After a median follow-up of 8.6 years, there were 45 confirmed subject deaths. HTLV-I infection did not convey a statistically significant excess risk of mortality (unadjusted HR 1.9, 95%CI 0.8-4.4; adjusted HR 1.9, 95%CI 0.8-4.6). HTLV-II was associated with death in both the unadjusted model (HR 2.8, 95%CI 1.5-5.5) and in the adjusted model (HR 2.3, 95%CI 1.1-4.9). No single cause of death appeared responsible for the HTLV-II effect. CONCLUSIONS: After adjusting for known and potential confounders, HTLV-II infection is associated with increased mortality among healthy blood donors. If replicated in other cohorts, this finding has implications for both HTLV pathogenesis and counseling of infected persons.

Blood Donors↗

The donor notification process from the donor's perspective.

BACKGROUND: Despite large numbers of blood donors being notified of abnormal infectious disease screening results, there has been little scientific study of the effects of this process. STUDY DESIGN AND METHODS: With a 28-item questionnaire, an anonymous mail survey was conducted of 4141 blood donors notified of 15 distinct categories of abnormal infectious disease screening and confirmatory test results. RESULTS: The survey had a 42 percent response rate, and 10 percent of the respondents did not recall being notified of their results. Of the 1556 respondents who recalled being notified, 27 percent contacted the blood center for further information, 60 percent discussed their results with a health care provider, and 73 percent of permanently or indefinitely deferred donors correctly understood their deferral status. Confusion and emotional upset were reported in 81 and 75 percent of notified donors, respectively. CONCLUSIONS: The notification process appears to achieve most of its aims in the majority of donors. Nevertheless, some donors did not understand that they were ineligible for future donation, and many donors were confused and upset. These data indicate that the adverse impact of notifying donors about abnormal test results needs to be considered when new blood donor screening tests and confirmatory algorithms are being licensed and implemented. Further studies of the effectiveness of newer revised donor notification materials are needed.

Adult↗

Respiratory and urinary tract infections, arthritis, and asthma associated with HTLV-I and HTLV-II infection.

Human T-lymphotropic virus types I and II (HTLV-I and -II) cause myelopathy; HTLV-I, but not HTLV-II, causes adult T-cell leukemia. Whether HTLV-II is associated with other diseases is unknown. Using survival analysis, we studied medical history data from a prospective cohort of HTLV-I- and HTLV-II-infected and -uninfected blood donors, all HIV seronegative. A total of 152 HTLV-I, 387 HTLV-II, and 799 uninfected donors were enrolled and followed for a median of 4.4, 4.3, and 4.4 years, respectively. HTLV-II participants had significantly increased incidences of acute bronchitis (incidence ratio [IR] = 1.68), bladder or kidney infection (IR = 1.55), arthritis (IR = 2.66), and asthma (IR = 3.28), and a borderline increase in pneumonia (IR = 1.82, 95% confidence interval [CI] 0.98 to 3.38). HTLV-I participants had significantly increased incidences of bladder or kidney infection (IR = 1.82), and arthritis (IR = 2.84). We conclude that HTLV-II infection may inhibit immunologic responses to respiratory infections and that both HTLV-I and -II may induce inflammatory or autoimmune reactions.

Adult↗