So great is the importance that everyone attaches to the physical condition of his own heart or those of his closest and dearest ones, that merely a minor disease would enduringly weigh on his mind.

The actual incidence of minor illness may be higher, as many people afflicted by food-borne disease suffer in the privacy of their homes.

Wildlife may be the canary in the coal mine for the dangers of climate change: even minor disturbances in the environment can influence its susceptibility to disease.