Recent household transmission of tuberculosis in England, 2010-2012: retrospective national cohort study combining epidemiological and molecular strain typing data.
Recent household transmission of tuberculosis in England, 2010-2012: retrospective national cohort study combining epidemiological and molecular strain typing data.
复制标题
DOI：
10.1186/s12916-017-0864-y
复制
发表时间：
2017-06-13
期刊：
影响因子：
9.3
通讯作者：
Thomas HL
中科院分区：
文献类型：
--
作者：
Lalor MK;Anderson LF;Hamblion EL;Burkitt A;Davidson JA;Maguire H;Abubakar I;Thomas HL
我们估计了英国由于最近的家庭传播而导致的结核病(TB)的比例，确定了与家庭传播者相关的因素，并调查了病例识别对后续病例治疗的及时影响。确定了2010至2012年间在英国报告的与另一例病例在同一家庭中的结核病病例；使用24个Miru-VNTR基因座菌株分型(ST)来识别可能最近传播的家庭病例。比较两组患者的治疗延迟指标和后续病例。在单变量和多变量分析中确定了作为家庭传播者的风险因素。总体而言，7.7%(1849/24,060)的结核病病例生活在与另一病例相同的家庭中。我们估计，3.9%是由于最近的家庭传播。67%(1242)的家庭配对没有ST数据。对于有ST数据的人，%(386)确认了，11%(66)可能和25%(155)驳斥了家庭传播。首发病例的治疗延迟中位数为65天，后续无症状病例的中位延迟时间为37天。成为家庭传播者的风险因素包括年龄在25岁以下，出生在英国的非洲黑人、印度人或巴基斯坦人，或者出生在索马里或罗马尼亚。这项研究对低发病率国家的家庭结核病接触者追踪有一些影响，包括减少后续家庭病例的诊断延迟的可能性，以及使用ST来确定何时在家庭外进行源头接触者追踪的好处。由于家庭中25%的结核病病例具有不协调的菌株，多个结核病病例的家庭不一定代表家庭传播。另外一个事实是，25%的家庭内指标病例只有肺外结核病，这表明，如果家庭接触者追踪仅限于肺结核病例(最近在英国指南中建议的那样)，家庭中更多的活动性结核病病例将被遗漏。我们的发现是，没有结核病世系与最近的家庭传播有关，与其他人相比，北京世系的传播率没有增加，这表明该世系不需要影响接触者追踪工作。接触者追踪方面的改进有可能减少低发病率国家的结核病传播。本文的在线版本(doi：10.1186/s12916-0170864-y)包含补充材料，授权用户可以使用。
We estimate the proportion of tuberculosis (TB) in England due to recent household transmission, identify factors associated with being a household transmitter, and investigate the impact that identification of a case has on time to treatment of subsequent cases. TB cases notified between 2010 and 2012 in England in the same household as another case were identified; 24 locus MIRU-VNTR strain typing (ST) was used to identify household cases with likely recent transmission. Treatment delay in index and subsequent cases was compared. Risk factors for being a household transmitter were identified in univariable and multivariable analyses. Overall, 7.7% (1849/24,060) of TB cases lived in a household with another case. We estimate that 3.9% were due to recent household transmission. ST data was unavailable for 67% (1242) of household pairs. For those with ST data, 64% (386) had confirmed, 11% probable (66) and 25% (155) refuted household transmission. The median treatment delay was 65 days for index cases and 37 days for subsequent asymptomatic cases. Risk factors for being a household transmitter included being under 25 years old, UK-born with Black African, Indian or Pakistani ethnicity, or born in Somalia or Romania. This study has a number of implications for household TB contact tracing in low incidence countries, including the potential to reduce the diagnostic delay for subsequent household cases and the benefit of using ST to identify when to conduct source contact tracing outside the household. As 25% of TB cases in households had discordant strains, households with multiple TB cases do not necessarily represent household transmission. The additional fact that 25% of index cases within households only had extra-pulmonary TB demonstrates that, if household contact tracing is limited to pulmonary TB cases (as recently recommended in UK guidelines), additional cases of active TB in households will be missed. Our finding that no lineage of TB was associated with recent household transmission and with no increased transmissibility in the Beijing lineage compared to others, suggests that the lineage need not impact contact tracing efforts. Improvements in contact tracing have the potential to reduce transmission of TB in low incidence countries. The online version of this article (doi:10.1186/s12916-017-0864-y) contains supplementary material, which is available to authorized users.