Home › Authors › New York Association for Improving the Condition of the Poor. Department of Social Welfare. Bureau of Public Health and Hygiene 👤 New York Association for Improving the Condition of the Poor. Department of Social Welfare. Bureau of Public Health and Hygiene 1 book Books by New York Association for Improving the Condition of the Poor. Department of Social Welfare. Bureau of Public Health and Hygiene Flies and diarrheal disease Flies and diarrheal disease 1915