American Outbreak.

Pellagra is a disease caused by a diet deficiency of nicotinamide, a B vitamin, and results in dermatitis (inflammation of the skin), diarrhea, dementia, and often death. Today the disease is rare even in undeveloped countries. First identified in Spain in 1735 by Don Pedro Casal, physician to King Philip V, pellagra was for many years thought to be nonexistent in America. Yet from about 1900 until the 1940s an epidemic swept through the country that accounted for more than three million cases and one hundred thousand deaths.

Growing Awareness.

In 1902 Dr. H. F. Harris reported a single case of pellagra in a Georgia farmer at the state's annual medical association meeting. Alabama physician George H. Searcy published in 1907 a description of eighty-eight cases at the state's insane asylum. The following year Dr. James Babcock identified cases among the insane in South Carolina. Later in 1908 the...