The traditional model for disease-the soil and the seed which under the right conditions can produce dis-ease/illness and disease in the individual or community.

The agent-bacterium, virus, toxin, carcinogen

The host-the individual genotype, phenotype, nutrition, immunity

The environment-temperature, humidity, employment, housing

Here

Social-Life on earth and in particular human life and activity

Ecological-The buffers-the oceans, the troposphere, the rain forests

Global-the world environment-temperature, weather, humidity,salinity,greenhouse gases, ozone