This paper analyzes the influence of wastewater treatment access of a region and the effect on public health improvement independent of its economy. The sample set is derived from 39 different nations. The study employs health, economic and environmental indicators such as gross national income, human development index; disease mortality due to diarrheal diseases, tuberculosis and malaria, access to sanitation, wastewater treatment and collection. It is necessary to extricate the impact of increased wastewater treatment access on disease mortality from that of increased national income and health care. Hence we observed this influence for very small ranges of human development. It was concluded that an increase in wastewater treatment availability reduces disease mortality, independent of an increase in income or sanitation. Trends in the lack of wastewater treatment with the logarithm of disease mortality had correlation coefficients (r(2)) of 0.35-0.5 at a high significance (P < 0.001). Previous studies have emphasized the relation between improved sanitation and public health. This study reasserts the necessity for wastewater treatment in order to mitigate disease burden and mortality.