VICtorian Infectious Diseases Service, Melbourne Health, Melbourne, VIC, Australia.
Med J Aust. 2012 Oct 15;197(8):458-61. doi: 10.5694/mja12.10035.
To estimate the risk of active tuberculosis (TB) in immigrants to VICtoria, Australia, as a function of time since arrival and stratified by age group and region of origin. DESIGN, SETTING AND SUBJECT: Longitudinal study of the incidence of active TB in VICtorian immigrants, excluding New Zealanders, who arrived in Australia between 1975 and 2007. VICtorian immigration data were used to describe annual arrival cohorts by age and region of origin, and TB case notification data for 1995 to 2010 were matched to the cohorts. Survival analysis was performed to determine incidence rates of active TB.
Incidence of active TB, stratified by age, region of origin and time since arrival in Australia.
Incidence of active TB following immigration to Australia was highly dependent on region of origin, with the highest risks being in immigrants from South Asia and sub-Saharan Africa. For immigrants from high-risk regions (Asia, Africa and the Pacific), the incidence of active TB infection was 100-150 per 100 000 person-years in the first 6 years following immigration. Overall, we estimate that 50% of TB occurred within 7 years of arrival. A bimodal age distribution was evident, with peaks of incidence in 20-24-year-olds and 70-74-year-olds.
Our data show that substantial risk of TB in VICtorian immigrants persists well beyond the first 2-3 years following arrival, and that risk is highly dependent on region of origin. The regional dependence suggests that public health strategies would benefit from more refined regional stratification of risk, which could be used to determine risk thresholds for the use of TB prevention strategies and predict rates of TB in Australia following particular patterns of immigration.
估计澳大利亚维多利亚州移民中活动性结核病（TB）的风险，该风险随到达时间的变化而变化，并按年龄组和原籍地区进行分层。
设计、设置和研究对象：对维多利亚州移民中活动性 TB 发病率的纵向研究，不包括 1975 年至 2007 年期间抵达澳大利亚的新西兰人。维多利亚州移民数据用于描述按年龄和原籍地区划分的每年到达的移民群体，1995 年至 2010 年的 TB 病例通知数据与这些群体相匹配。进行生存分析以确定活动性 TB 的发病率。
按年龄、原籍地区和到达澳大利亚后的时间分层的活动性 TB 发病率。
移民澳大利亚后活动性 TB 的发病率高度取决于原籍地区，来自南亚和撒哈拉以南非洲的移民风险最高。对于来自高风险地区（亚洲、非洲和太平洋地区）的移民，在移民后的头 6 年内，活动性 TB 感染的发病率为每 10 万人年 100-150 例。总体而言，我们估计 50%的 TB 发生在到达后 7 年内。年龄分布呈双峰型，发病率高峰在 20-24 岁和 70-74 岁之间。
我们的数据表明，维多利亚州移民中存在大量的 TB 风险，并且在到达后的头 2-3 年之后仍然存在，而且风险高度依赖于原籍地区。这种区域依赖性表明，公共卫生策略将受益于更精细的风险区域分层，这可以用于确定使用 TB 预防策略的风险阈值，并预测澳大利亚在特定移民模式下的 TB 发病率。
