MARION, Ala. — When Patricia Church, a 41-year-old warehouse worker, felt sick recently, she suspected that she had a cold. But she also feared something more deadly that has been going around this small, impoverished city: tuberculosis.

“I feel like I had been around someone that had it, and I might die from it if I don’t find out whether I got it or not and get it treated,” Ms. Church said after she learned last week that she did not have the disease. “I was nervous. I was real nervous.”

Marion is in the throes of a tuberculosis outbreak so severe that it has posted an incidence rate about 100 times greater than the state’s and worse than in many developing countries. Residents, local officials and medical experts said the struggle against the outbreak could be traced to generations of limited health care access, endemic poverty and mistrust — problems that are common across the rural South.

“There’s not a culture of care-seeking behavior unless you’re really sick,” said Dr. R. Allen Perkins, a former president of the Alabama Rural Health Association. “There’s not support for local medical care, so when something like this happens, you have a health delivery system that’s unprepared.”