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11.
《Vaccine》2016,34(30):3443-3446
We compared ≥4-fold increases in antibody titers by hemagglutination inhibition assay to RT-PCR results among 42 adults with PCR-confirmed influenza A virus illnesses. Serologic sensitivity was higher among unvaccinated (69%, 95% confidence interval [CI] = 48–90%) than vaccinated healthcare personnel (38%, 95% CI = 29–46%) in a 2010–11 prospective cohort.  相似文献   
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目的 了解浙江省新型毒品使用者艾滋病、梅毒和丙型肝炎(丙肝)感染水平、相关行为特征以及相互关系。方法 2011年在浙江省6个城市对戒毒人员进行匿名问卷调查,调查内容包括社会人口学、使用毒品种类、性行为、接受干预情况,并采集血液进行艾滋病、梅毒和丙肝抗体检测。利用SPSS 15.0统计软件进行数据分析。结果 共调查3 253人,其中新型毒品使用者1 298人,占39.9%,北部和中部地区、女性、≤25岁年龄组、浙江省户籍和有商业性性行为的吸毒者中使用新型毒品的比例较高。1 298例新型毒品使用者中,使用冰毒者占91.2%,HIV抗体阳性率为0.1%(95%CI:0.0%~0.2%),梅毒抗体阳性率为8.1%(95%CI:6.6%~9.6%),丙肝抗体阳性率为17.3%(95%CI:15.2%~19.4%);艾滋病知识知晓率为12.7%,有注射吸毒史者占9.2%,最近一年有商业性性行为者占29.6%。曾接受安全套发放和咨询的比例为33.4%,曾接受艾滋病检测的比例为14.0%。多因素分析表明,来自中部和南部地区的新型毒品使用者的梅毒感染、丙肝感染和有注射吸毒行为比例高于来自北部地区者;女性是梅毒感染的相关因素;曾注射吸毒和最近一年有商业性性行为与丙肝感染相互关联;曾注射吸毒行为与最近一年商业性性行为相互关联。男性、浙江省户籍及未接受过安全套发放和咨询者更有可能发生商业性性行为。结论 新型毒品使用者梅毒和丙肝感染水平高,不安全行为发生率高,接受干预服务比例低,提示需要提高对该人群的艾滋病、梅毒和丙肝感染风险的认识,设计制定针对该人群的有效干预措施,扩大干预覆盖率。  相似文献   
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《Vaccine》2015,33(32):3887-3893
ObjectivesTo estimate the predictive value of self-reported hepatitis A vaccine (HepA) receipt for the presence of hepatitis A virus (HAV) antibody (anti-HAV) from either past infection or vaccination, as an indicator of HAV protection.MethodsUsing 2007–2012 National Health and Nutrition Examination Survey data, we assigned participants to 4 groups based on self-reported HepA receipt and anti-HAV results. We compared characteristics across groups and calculated three measures of agreement between self-report and serologic status (anti-HAV): percentage concordance, and positive (PPV) and negative (NPV) predictive values. Using logistic regression we investigated factors associated with agreement between self-reported vaccination status and serological results.ResultsDemographic and other characteristics varied significantly across the 4 groups. Overall agreement between self-reported HepA receipt and serological results was 63.6% (95% confidence interval [CI] 61.9–65.2); PPV and NPV of self-reported vaccination status for serological result were 47.0% (95% CI 44.2–49.8) and 69.4% (95% CI 67.0–71.8), respectively. Mexican American and foreign-born adults had the highest PPVs (71.5% [95% CI 65.9–76.5], and 75.8% [95% CI 71.4–79.7]) and the lowest NPVs (21.8% [95% CI 18.5–25.4], and 20.0% [95% CI 17.2–23.1]), respectively. Young (ages 20–29 years), US-born, and non-Hispanic White adults had the lowest PPVs (37.9% [95% CI 34.5–41.5], 39.1% [95% CI, 36.0–42.3], and 39.8% [36.1–43.7]), and the highest NPVs (76.9% [95% CI 72.2–81.0, 78.5% [95% CI 76.5–80.4)], and 80.6% [95% CI 78.2–82.8), respectively. Multivariate logistic analyses found age, race/ethnicity, education, place of birth and income to be significantly associated with agreement between self-reported vaccination status and serological results.ConclusionsWhen assessing hepatitis A protection, self-report of not having received HepA was most likely to identify persons at risk for hepatitis A infection (no anti-HAV) among young, US-born and non-Hispanic White adults, and self-report of HepA receipt was least likely to be reliable among adults with the same characteristics.  相似文献   
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High HIV incidence has been reported in young men who have sex with men (YMSM) in North America and Western Europe, but there are limited data from Southeast Asia suggesting MSM may be the driver of the HIV epidemic in this region. We described HIV incidence and risk factors among 494 YMSM enrolled in a cohort study in Bangkok, Thailand. The HIV incidence was 7.4 per 100 person-years. In multivariable analysis, reporting use of an erectile dysfunction drug in combination with club drugs, having receptive or both insertive and receptive anal intercourse with men, having hepatitis A infection, having rectal Chlamydia trachomatis, having hepatitis B infection prior to HIV seroconversion, and reporting not always using condoms with male steady partners were significantly associated with HIV incidence in YMSM. Reduction in new HIV infections in YMSM are critical to reach targets set by Thailand and the region.  相似文献   
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Characterizing human immunodeficiency virus (HIV) expression in semen during primary infection remains essential to understanding the risk of sexual transmission. This investigation represents the first systematic evaluation of male genital tract shedding to use a nonhuman primate model, including the impact of exposure route and viral virulence. Male macaques were inoculated with either a chronic disease-causing virus (HIV-2(GB122); n=4 intravenous; n=4 intrarectal) or an acutely pathogenic simian/HIV strain (SHIV(89.6P); n=2 intravenous). All macaques were systemically infected, and seminal plasma virion-associated RNA (vRNA) levels were approximately 10-fold lower than those in blood. In HIV-2(GB122) infection, seminal virus was delayed by 1-2 weeks compared with that in blood. Intrarectal inoculation resulted in a shorter duration of seminal vRNA expression and intermittent seminal cell provirus. No delays, higher peaks ( approximately 50-fold), or longer durations in seminal virus expression were noted for SHIV(89.6P) infection. This novel model definitively establishes that virus dissemination results in early peak seminal levels and provides a basis for evaluating interventions targeting male genital tract expression.  相似文献   
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Episodic drug use and binge drinking are associated with HIV risk among substance-using men who have sex with men (SUMSM), yet no evidence-based interventions exist for these men. We adapted personalized cognitive counseling (PCC) to address self-justifications for high-risk sex among HIV-negative, episodic SUMSM, then randomized men to PCC (n = 162) with HIV testing or control (n = 164) with HIV testing alone. No significant between-group differences were found in the three primary study outcomes: number of unprotected anal intercourse events (UAI), number of UAI partners, and UAI with three most recent non-primary partners. In a planned subgroup analysis of non-substance dependent men, there were significant reductions in UAI with most recent non-primary partners among PCC participants (RR = 0.56; 95 %CI 0.34–0.92; P = 0.02). We did not find evidence that PCC reduced sexual risk behaviors overall, but observed significant reductions in UAI events among non-dependent SUMSM. PCC may be beneficial among SUMSM screening negative for substance dependence.  相似文献   
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Infection with human immunodeficiency virus (HIV) disrupts the balance among γδ T cell subsets, with increasing Vδ1+ cells and substantial depletion of circulating Vδ2+ cells. Depletion is an indirect effect of HIV in CD4-negative Vδ2 cells, but is specific for phosphoantigen-responsive subpopulations identified by the Vγ2-Jγ1.2 (also called Vγ9-JγP) T cell receptor rearrangement. The extent of cell loss and recovery is related closely to clinical status, with highest levels of functional Vδ2 cells present in virus controllers (undetectable viremia in the absence of antiretroviral therapy). We review the mechanisms and clinical consequences for Vδ2 cell depletion in HIV disease. We address the question of whether HIV-mediated Vδ2 cell depletion, despite being an indirect effect of infection, is an important part of the immune evasion strategy for this virus. The important roles for Vδ2 cells, as effectors and immune regulators, identify key mechanisms affected by HIV and show the strong relationships between Vδ2 cell loss and immunodeficiency disease. This field is moving toward immune therapies based on targeting Vδ2 cells and we now have clear goals and expectations to guide interventional clinical trials.  相似文献   
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