Tuberculosis rates among foreign-born people living in the United States have fallen by nearly 20%, according to a Centers for Disease Control and Prevention report in PLOS One.

From 2007 to 2011, there was an overall decline of 1,456 TB cases (–19.3%) among all foreign-born people in the United States, wrote Dr. Brian Baker of the CDC’s division of tuberculosis elimination, and colleagues. The largest relative declines in case counts were among those who emigrated within the past 3 years from Mexico (–56.1%, –270 cases); the Philippines (–52.5%, –180 cases), and India (–39.8%, –101 cases).

Factors contributing to the declines varied by country of origin.

Among recent entrants born in Mexico, 80.7% of the case count decline was attributable to a decrease in people from that country coming to the United States, while declines among recent entrants from the Philippines, India, Vietnam, and China were almost exclusively (95.5%-100%) the result of decreases in TB case rates.

TB rates also declined among foreign-born individuals who have been in the United States for 3 years or more, the investigators noted. There was an 8.9% decline in this population (–443 cases) that resulted entirely from a decrease in the TB case rate.

Strategies such as investment in overseas TB control, as well as expanded testing of high-risk subgroups living in the United States, “will be necessary to achieve further declines in TB morbidity among foreign-born persons,” the authors wrote.

Read the article in PLOS One (2016 Feb 10. doi: 10.1371/journal.pone.0147353 )