TB at an All-Time Low, but Still Affects Some Groups

Emma Hitt, PhD

March 23, 2012

March 23, 2012 — Preliminary data from the US Centers for Disease Control and Prevention (CDC) show that tuberculosis (TB) reached an all-time low in the United States in 2011, but the news is not all good: TB rates are several times higher among certain racial/ethnic minorities than among whites.

The CDC's National TB Surveillance System tabulated a total of 10,521 TB cases in 2011, representing 3.4 cases per 100,000 population and a decline of 6.4% compared with 2010.

Although declining overall, rates still remained 7 times higher for Hispanics, 8 times higher for blacks, and 25 times higher for Asians than for whites (prevalence, 0.8 cases per 100,000 population).

"Asians now surpass Hispanics as the racial/ethnic group with the largest number of TB cases," states a CDC news release. In addition, the TB rate for foreign-born persons was 12 times higher than that for those born in the United States.

In 2010, the most recent year for which complete resistance data are available, multidrug-resistant TB remained stable at 1.3% of cases (n = 109). However, 4 cases of extensively-drug resistant (XDR) TB were reported in 2011. XDR TB is defined as TB that is resistant to isoniazid and rifampin, fluoroquinolones, and at least 1 of 3 injectable second-line drugs (ie, amikacin, kanamycin, or capreomycin).

The CDC recently issued guidelines on an abbreviated treatment course, which would reduce the doses required for treatment from 270 daily doses of isoniazid to just 12 once-weekly doses of rifapentine and isoniazid used in combination.

"The 12-dose regimen adds to other current latent TB infection treatment options and does not replace those treatment options," the CDC states in an overview of the fact sheet.

"CDC is currently working to increase awareness of this new regimen among health care providers for use in treating patients with latent TB infection," they add.