“…A ‘ new epidemiology’ (Warin 1959) has appeared. Infectious diseases consultants today are concerned with a much larger range of infections such as poliomyelitis and the varied assortment of viruses which may infect the central nervous system giving rise to clinically similar syndromes, influenza and a host of new viruses now being identified with acute respiratory infections, infectious mononucleosis and infectious hepatitis in which search for the causal agent must be more assiduously pursued, as well as the still prevalent intestinal infections such as salmonellosis, dysentery and gastro‐enteritis of infants.…”