A call for the destruction of smallpox virus stores.

Finally, Wallace is correct that broader socioeconomic changes can have a determining effect on tuberculosis morbidity. Cases increased dramatically during the Industrial Revolution and then decreased steadily, even before the advent of antituberculosis agents.2 Nevertheless, effective tuberculosis control programs can reduce disease incidence much more quickly than socioeconomic improvement.3 As I noted previously, "as [tuberculosis] once again begins to decline in the United States and leaves the front pages, our challenge will be to persevere. We must expand effective outreach programs ... provide services to underserved populations . . . target services ... conduct the epidemiologic investigations . . . and work to improve the social and economic environment that provides the substrate for the tuberculosis epidemic in the United States and abroad."4 0 Thomas R. Frieden, MD, MPH