Overview

The twentieth century was a period of rapid scientific development and unprecedented progress in the biomedical sciences. During the first half of the twentieth century, advances in science—especially in microbiology, immunology, biochemistry, endocrinology, and nutrition—revolutionized medical theory and practice. Even though anesthesia and antiseptic techniques had transformed surgery in the nineteenth century, surgeons could not cope with blood loss, shock, or postsurgical infections until well into the twentieth century. Advances in biochemistry and physiology led to the development of more precise diagnostic tests and more effective therapies. The development of new instruments and laboratory techniques accelerated the growth of specialization within the medical profession and led to major changes in clinical medicine.

The identification and isolation of the microbial agents that caused many of the most important infectious diseases facilitated public health campaigns against epidemic diseases. Advances in preventive and therapeutic...