MMWR Morb Mortal Wkly Rep. 2014 Mar 21;63(11):234-6.
For more than two decades, as the number of tuberculosis (TB) cases overall in the United States has declined, the proportion of cases among foreign-born persons has increased. In 2013, the percentage of TB cases among those born outside the country was 64.6%. To address this trend, CDC has developed strategies to identify and treat TB in U.S.-bound immigrants and refugees overseas. Each year, approximately 450,000 persons are admitted to the United States on an immigrant visa, and 50,000-70,000 are admitted as refugees. Applicants for either an immigrant visa or refugee status are required to undergo a medical examination overseas before being allowed to travel to the United States. CDC is the federal agency with regulatory oversight of the overseas medical examination, and panel physicians appointed by the U.S. Department of State perform the examinations in accordance with Technical Instructions (TI) provided by CDC's Division of Global Migration and Quarantine (DGMQ). Beginning in 1991, the algorithm for TB TI relied on chest radiographs for applicants aged ≥15 years, followed by sputum smears for those with findings suggestive of TB; no additional diagnostics were used. In 2007, CDC issued enhanced standards for TB diagnosis and treatment, including the addition of sputum cultures (which are more sensitive than smears) as a diagnostic tool and treatment delivered as directly observed therapy (DOT). This report summarizes worldwide implementation of the new screening requirements since 2007. In 2012, the year for which the most recent data are available, 60% of the TB cases diagnosed were in persons with smear-negative, but culture-positive, test results. The results demonstrate that rigorous diagnostic and treatment programs can be implemented in areas with high TB incidence overseas.
二十多年来,尽管美国的结核病(TB)总病例数一直在下降,但在外国出生的人群中的比例却在增加。2013 年,国外出生的结核病病例比例为 64.6%。为了解决这一趋势,CDC 制定了在海外识别和治疗赴美移民和难民中的结核病的策略。每年,约有 45 万人持移民签证进入美国,5 万至 7 万人作为难民进入美国。无论是移民签证申请人还是难民申请人,在获准前往美国旅行之前,都必须在海外接受体检。CDC 是对海外体检进行监管的联邦机构,美国国务院指定的体检医生按照 CDC 全球移徙和检疫司(DGMQ)提供的技术指示(TI)进行体检。从 1991 年开始,TB TI 的算法依赖于 15 岁及以上申请人的胸部 X 光片,然后对有结核病迹象的人进行痰涂片检查;没有使用其他诊断方法。2007 年,CDC 发布了结核病诊断和治疗的强化标准,包括将痰液培养(比涂片更敏感)作为一种诊断工具,以及直接观察治疗(DOT)。本报告总结了自 2007 年以来全球实施新筛查要求的情况。在 2012 年,也就是最新数据可用的那一年,诊断出的结核病病例中有 60%是涂片阴性但培养阳性的人。结果表明,在海外结核病发病率高的地区,可以实施严格的诊断和治疗方案。