Tuberculosis cases reach record low, but world health threat remains

Last year, the U.S. had its lowest number of tuberculosis cases ever recorded, with fewer than 10,000 cases, but experts say the goal of eliminating the disease remains elusive and more needs to be done to find effective treatments.

A total of 9,588 cases of tuberculosis were reported in the U.S. in 2013, a 4% decline from 2012 according to a new report in the Centers for Disease Control and Prevention's latest Morbidity and Mortality Weekly Report, released Thursday.

More than half of cases occurred in just four states—California, Texas, New York and Florida—accounting for 51% of TB patients, an increase from 49% in 2012, according to the study.

Despite the overall decrease, the report found large racial disparities. Rates among Blacks and Hispanics were seven times higher than for Whites, according to the report, while Asians had 18 TB cases per 100,000 people, a rate nearly 26 times greater than that for Whites.

Rates remained higher among foreign-born persons, with incidence rates 13 times greater than those born in the U.S. With this in mind, TB screenings for immigrants and refugees entering the country have been updated, resulting in more disease identification, according to the CDC. The agency estimated that new requirements for immigrants to receive sputum-culture tests identified 660 TB cases in 2012, in addition to 14 cases that were found to be multi-drug resistant strains of the disease. Those discoveries saved an estimated $15 million in avoided medical costs.

But some health experts warn that government efforts to find more effective treatments for the disease have not gone far enough, considering the potential global health threat that TB poses.

“Even though it’s certainly not as much of a public health problem here as it is in many other areas of the world, it’s still a very expensive disease and very scary,” said Kari Stoever, vice president for external affairs for not-for-profit biotechnology firm Aeras, which is working to develop a new TB vaccine.

In a recent report published in the CDC journal Emerging Diseases, the costs associated with TB treatment were estimated to average $17,000 per person for uncomplicated cases.

In TB cases where individuals were found to be resistant to the most common treatment drugs, known as multidrug-resistant TB, treatment costs went up significantly, averaging $134,000 per person. And for those found to be extensively drug-resistant to even the most potent TB treatments, average treatment costs were $430,000 per person. “When you look at even a local health department budget that gets hit with one extensive drug-resistant outbreak, it can be catastrophic,” Stoever said.

Typically TB attacks the lungs and is spread through the air. It can lay dormant in a person’s system throughout their lifetime, making the number of people who are infected much greater than the estimated 9 million cases of TB worldwide. Health officials estimate that more than one-third of the world’s population is infected with the bacterium that causes TB, with close to 10% actually becoming sick from the disease, usually as the result of developing immune-system weakness.

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