Back to the future: Covid-19 and the recurring debate over social determinants of disease, and health.

Since the 1980s, a large literature has developed on the social determinants of health, primarily non-communicable diseases for which mortality and morbidity can be shown to change across a socioeconomic gradient. Primarily regional or national in focus, they are joined, today, with an increasing focus on international health and the effect of inequalities between nations effect disease generation and spread. Similar and earlier literatures first considered socioeconomic factors influencing disease incidence and intensity primarily at local and regional levels. One such literature was primarily "sanitarian," focusing on general infrastructure needs (safe water, for example) to create a beter health environment. A second, primarily nineteenth century literature focused on social inequalities and the epidemic diseases in specific populations. This paper seeks to review these separate foci and then combine them into a more comprehensive understanding of both the general and specific determinants of health and disease at local, national, and international scales of address. It notes that while disease dynamics have been long known that current literatures typically consider socioeconomic determinants at local, national, and global scales as a new phenomenon.