Tinea pedis
Common cold
Heart Disease
arthritis
Obesity
i would say rhinovirus(common cold).
Cardiovascular disease (and 2nd is cancers, with 3rd being strokes).
Heart disease
arthritis
cystic fibrosis
Flu __ It's likely malaria.
cystic fibrosis
If you mean infectuous disease. The most common deadly disease in the US in the early 1900s was probably tuberculosis. In the last half of the 1900s it was probably Influenza (the flu). If you mean any disease, then I think it would be heart disease for the entire century.