Tuberculosis Among Foreign-born Persons in the United States.

The authors analyzed the cases of tuberculosis that occurred in the United States among foreign-born persons from 2001 through 2006. During this period, 46,970 cases of TB were reported among foreign-born persons, of whom 28% were recent entrants who were, within 2 years of entry to the United States, and 69% were not recent entrants. TB case rates were highest in recent entrants. When analyzed by country of birth, case rates in recent entrants were 3-7 times higher than among non-recent entrants. Recent entrants born in sub-Saharan Africa and Southeast Asia had annual case rates > 250/100,000 persons. Cases in persons born in sub-Saharan Africa and southeast Asia account for 53% of all TB cases in foreign-born individuals, although people born in these regions account for only 22% of the foreign-born population in the United States. Recent entrants from Central America, Eastern Europe, the Pacific Islands, and South, East, and Central Asia had annual case rates of > 100/100,000 persons. Moreover, TB rates among foreign-born persons remained at > 10/100,000 persons even among those who have lived in the United States for more than 2 decades, 4 times higher than among U.S.-born persons. When analyzed by age at arrival to the United States, TB rates rose with increased age at arrival. In recent entrants, annual case rates increased from 25-30/100,000 persons in those who arrived at age < 5 years, to > 100/100,000 persons in those who arrived at age > 50 years. Similarly, in non-recent entrants, the annual case rates were increased from 5/100,000 persons in those who arrived at age < 5 years, to > 60/100,000 persons in those who arrived at age > 60 years. Drug resistance is another problem in foreign-born persons with tuberculosis, occurring in 10-11% of bacterial isolates compared to 4% in U.S.-born persons. INH-resistance was highest in recent entrants from Vietnam (20%), Peru (18%), the Philippines (17%), and China (16%). Multidrug-resistant TB occurred in 6% of recent entrants from Peru and China, compared to 0.6% among U.S.-born persons. The authors assessed pre-arrival screening, which currently includes chest radiography in persons aged 15 year or older, plus sputum smear if found to have abnormal radiograph. They found that 4499 foreign-born persons were reported with TB within 3 months of arrival to the United States, with 91% having pulmonary disease. Abnormal chest radiographs and positive sputum smears were found in 1211, which could have been identified by current overseas screening. Another 1502 had an abnormal chest radiograph, negative sputum, but positive sputum culture. Screening with CXR, sputum smear and culture would identify the latter group of individuals, 46% of whom are from Vietnam or the Philippines. [ABSTRACT FROM AUTHOR]