CDC officials say a woman with an extremely rare form of tuberculosis came to the US from India and traveled to three different states before being diagnosed with an active case of the disease. Now she's isolated at a National Institutes for Health clinic in Maryland, and authorities are trying to track down "hundreds of people" who may have come into contact with her, NBC News reports. If it were just a simple case of TB, there wouldn't be such a brouhaha—but the unnamed patient has extensively drug-resistant TB, or XDR TB, which doesn't respond to some of the most powerful anti-TB drugs, per the World Health Organization. Although the disease is rare—the CDC says only 63 cases of it were noted between 1993 and 2011—TB bacteria can enter the air via coughs or sneezes and remain there for several hours, the agency notes.
After spending time in India—the country with the largest number of TB cases in 2013, according to WHO—the woman flew back to Chicago in April, then traveled to Missouri and Tennessee over the next seven weeks, notes NBC. CNN points out as many as 8 weeks can pass between exposure and a positive TB test. A spokeswoman for the McHenry County Health Department in Illinois tells the Chicago Tribune it's keeping an eye on some people the woman was in close contact with and that the general public is likely not at risk. An NIH statement says the patient is being treated in a room "specifically designed for handling patients with respiratory infections, including XDR-TB," per NBC; the CDC says she's in stable condition. The CDC reports only 30% to 50% of XDR TB cases can be cured, and treatment can take years, with doctors even performing surgery to remove infected areas.