IN THE forty-seven years that have elapsed since the publication of the third edition of Osler's famous textbook, one familiar paragraph has remained unchanged in all revisions. "Pneumonia may well be called the friend of the aged. Taken off by it in an acute, short, not often painful illness, the old escape those 'cold gradations of decay' that make the last stage of all so distressing."1 Modern chemotherapy has made it necessary to revise this famous dictum. Today it is almost commonplace of clinical experience to see old persons recover from acute pulmonary infections, in spite of cardiovascular or pulmonary complications, when actively treated with agents such as the sulfonamide compounds and antibiotics such as penicillin, in conjunction with inhalation of oxygen and measures to combat the associated diseases.
In a disease in which the incidence has been reported as high as 2,000 per hundred thousand in persons over