Tuberculosis In America: Who Is Affected?

This World Tuberculosis Day, a day aimed at raising public awareness about the disease, there's cause for celebration -- in the U.S., at least.

TB, which is a bacterial infection affecting the lungs that's spread through coughing and sneezing, has hit an all-time low in this country, according to new data from the CDC. In 2010, approximately 11,000 cases of TB were reported -- a decline of nearly 4 percent from 2009.

But the CDC's goal of eliminating the disease by 2010, which was established 1989, was not met. And the new data shows that TB continues to disproportionately affect racial and ethnic minority communities.

"TB rates among Hispanics, non-Hispanic blacks, and Asians were 7, 8, and 25 times greater, respectively, than among non-Hispanic whites," the report from this week's Morbidity and Mortality Weekly Report states.

It added that foreign-born persons living in the U.S. have a TB infection rate 11 times higher than their native-born counterparts.

The CDC has highlighted several factors explaining why TB rates are higher in minorities and foreign-born persons, like the increased likelihood of picking up an infection in their country of origin. It also points to an unequal distribution of TB risk factors, particularly HIV, among minority groups. HIV weakens a person's immune system, making him or her particularly susceptible to TB. The new data shows that 9 percent of people who have TB are co-infected with HIV.

A lack of adequate screening and preventive therapy is another reason why TB rates in immigrant communities are particularly high, according to NYU's Center for Immigrant Health.

"An alarmingly low percentage of immigrants and refugees complete PPD screening [the tuberculosis skin test]," states the center's website. "And of those who do and have significant results, only a small percentage receives appropriate follow-up."

Left untreated, the Mayo Clinic reports, TB can be fatal, infecting your brain, kidneys, heart and even your bones.

The theme of this year's World TB day, which falls on March 24 in commemoration of the day Dr. Robert Koch discovered its cause, is "On the move against tuberculosis." The idea is to highlight new innovations in the field of TB treatment and testing, in order to inspire others to move research forward, too.