B notifications and the detection of tuberculosis among foreign-born recent arrivals in California

To evaluate the effectiveness and limitations of the B notification program for detecting tuberculosis among recent foreign-born arrivals in California.

Retrospective cohort study. All foreign-born visa holders with a B notification who arrived in California from January 1992 through September 1995 (n = 27 412) were matched with a listing of foreign-born persons who arrived in the US during the same time period and who were reported to have active tuberculosis in California within one year of their arrival from January 1992 through September 1996 (n = 2547).

Overall, 3.5% (95% confidence interval 3.3%, 3.8%) of all persons with a B notification were reported to have active tuberculosis within a year of arrival. Recent arrivals with a B notification and tuberculosis accounted for 38% of all foreign-born cases of tuberculosis reported within one year of arrival. Compared to recent arrivals without a B notification, those with a B notification were more likely to have pulmonary tuberculosis, less likely to have smear-positive pulmonary disease and reported with tuberculosis sooner after their arrival in the US. The B notification program was not able to identify 87% of the smear-positive pulmonary tuberculosis cases in adults, and did not identify 99% of these highly infectious cases among Latin Americans.

Although the evaluation of persons who enter the US with B notifications has a high yield for identifying active tuberculosis cases, it was not able to identify the majority of recent arrivals with the most infectious form of tuberculosis.