Division of Clinical Microbiology and Molecular Medicine, All India Institute of Medical Sciences, New Delhi, India.
PLoS One. 2013 Jul 26;8(7):e69730. doi: 10.1371/journal.pone.0069730. Print 2013.
Tuberculosis (TB), caused by Mycobacterium tuberculosis, is one of the leading causes of mortality and morbidity across all age groups throughout the world, especially in developing countries.
METHODOLOGY/PRINCIPAL FINDINGS: In this study, we have included 432 open index cases with their 1608 household contacts in a prospective cohort study conducted from May 2007 to March 2009. The follow-up period was 2 years. All Index cases were diagnosed on the basis of suggestive signs and symptoms and sputum being AFB positive. Among the 432 index patients, 250 (57.9%) were males and 182 (42.1%) females; with mean age of 34 ± 14.4 yr and 26 ± 11.1 yr, respectively. Out of 1608 household contacts, 866 (53.9%) were males and 742 (46.1%) females; with mean age of 26.5 ± 15.8 and 26.5 ± 16.0 yr, respectively. Of the total 432 households, 304 (70.4%) had ≤ 4 members and 128 (29.6%) had ≥ 5 members. The median size of the family was four. Of the 1608 contacts, 1206 were able to provide sputum samples, of whom 83 (6.9%) were found MTB culture positive. Household contacts belonging to adult age group were predominantly (74, 89.2%) infected as compared to the children (9, 10.8%). On screening the contact relationship status with index patients, 52 (62.7%) were first-degree relatives, 18 (34.6%) second-degree relatives and 12 (14.5%) spouses who got infected from their respective index patients. Co-prevalent and incident tuberculosis was found in 52 (4.3%) and 31 (2.6%) contacts, respectively. In incident cases, the diagnosis could be made between 4 to 24 months of follow-up, after their baseline evaluation.
Active household contact investigation is a powerful tool to detect and treat tuberculosis at early stages and the only method to control TB in high-TB-burden countries.
结核病（TB）由结核分枝杆菌引起，是全世界所有年龄段人群中导致死亡和发病的主要原因之一，尤其在发展中国家。
方法/主要发现：在这项研究中，我们纳入了 432 例开放性索引病例及其 1608 名家庭接触者，进行了一项从 2007 年 5 月至 2009 年 3 月进行的前瞻性队列研究。随访时间为 2 年。所有索引病例均根据提示性症状和痰 AFB 阳性诊断。在 432 例索引患者中，250 例（57.9%）为男性，182 例（42.1%）为女性；平均年龄分别为 34 ± 14.4 岁和 26 ± 11.1 岁。在 1608 名家庭接触者中，866 名（53.9%）为男性，742 名（46.1%）为女性；平均年龄分别为 26.5 ± 15.8 岁和 26.5 ± 16.0 岁。在总共 432 个家庭中，304 个（70.4%）有≤4 名成员，128 个（29.6%）有≥5 名成员。家庭规模中位数为 4。在 1608 名接触者中，有 1206 人能够提供痰样本，其中 83 人（6.9%）被发现 MTB 培养阳性。与儿童（9 名，10.8%）相比，成人年龄组的家庭接触者主要（74 名，89.2%）受到感染。在筛查与索引患者的接触关系状态时，52 名（62.7%）是一级亲属，18 名（34.6%）是二级亲属，12 名（14.5%）是配偶，他们分别从各自的索引患者那里感染。共发现 52 例（4.3%）和 31 例（2.6%）接触者并发和新发结核病。在新发病例中，在基线评估后 4 至 24 个月的随访期间可以做出诊断。
积极的家庭接触者调查是早期发现和治疗结核病的有力工具，也是在高结核病负担国家控制结核病的唯一方法。
