People from racial and ethnic minorities and foreign-born residents continue to be disproportionately affected by TB, the CDC said.

Four states -- California, Florida, New York and Texas -- reported more than 500 TB cases each in 2008. The TB rate among foreign-born residents was 20.2 cases per 100,000, which is 10 times higher than the two cases per 100,000. In 2008, TB rates ranged from 0.5 per 100,000 in North Dakota to 9.6 per 100,000 in Hawaii, the study said. Rates among Hispanics, blacks and Asians were 7.5, 8.1 and 23.4 times higher, respectively, than among whites in 2008. Centers for Disease Control and Prevention reported 12,898 new cases of TB in 2008, which equals 4.2 cases per 100,000 people.

Although 33 states and the District of Columbia reported lower rates in 2008 than in 2007, 17 states had higher rates. Combined, these four states accounted for 49.2% of all TB cases in the country last year. In 2007, five states had at least 500 cases, and seven states recorded that many in 2006.

However, the CDC report also noted that progress in eliminating tuberculosis has slo in recent years, with a 3.8% average annual rate of decline between 2000 and 2008, compared with a 7.3% rate of decline from 1993 to 2000.