Baltimore has done the best job subduing tuberculosis at a time when the disease has exploded in many American cities.
Its method has been simple: dispatching public health nurses to watch patients take their medicine.
Baltimore's TB rate dropped 52 percent between 1981 and 1992, a period when poverty, drug use and the vulnerability of AIDS patients caused the respiratory disease to rebound nationally.
A comparative study of urban TB rates in cities such as New fTC York, Newark, N.J., and Atlanta appears in today's Journal of the American Medical Association.
Dr. C. Patrick Chaulk, an infectious disease specialist with the Johns Hopkins School of Medicine, said Baltimore's program of "directly observed therapy" kept patients from succumbing to the natural tendency to quit taking medications as soon as symptoms subside.
When TB patients stop taking their antibiotics, they allow the disease to spread and mutate into new strains that are harder and more expensive to treat.
Patients must often take as many as 20 pills at a time, at first daily and then at longer intervals over a span of six months to make the treatment stick.
"If you want to design a treatment plan that was geared to failing, it's TB treatment that is unsupervised, giving people pocketfuls of pills that cause side effects -- nausea, vomiting, not feeling well -- that you have to take for six months," said Dr. Chaulk, who also works in the city's TB clinic.
"As soon as you start feeling better, you're less inclined to take your medicines."
In his study, Dr. Chaulk tracked six cities that had the highest tuberculosis rates in 1981, the year when the disease rose out of a long slumber and re-emerged in urban America.
Those cities, in order of TB prevalence, were Miami, San Francisco, Newark, Atlanta, Washington and Baltimore.
Over the next 14 years, all the cities except Baltimore remained high in the rankings.
Disease rates rose 67 percent in Newark and 97 percent in Atlanta. In the other cities, it increased steadily before easing in recent years.
New York, which ranked fairly low in 1981, saw its rate skyrocket 132 percent.
By 1992, the latest year examined by the study, Baltimore ranked 28th.
The program was the inspiration of the late Dr. David M. Glasser, the city's assistant commissioner for preventive medicine. He began a limited program of directly observed therapy in the late 1970s.
By 1984, he had closed three of four walk-in treatment centers but greatly expanded the number of house calls made by department nurses.
Today, nurses manage more than 90 patients at any given time, delivering medications to people in their homes as well visiting them in shooting galleries and drug-treatment centers.