New Delhi, May 5 -- One of the front-line defenses individuals have against the spread of the coronavirus can feel decidedly low-tech: hand-washing.

In fact, it was 19th-century Hungarian physician Ignaz Semmelweis who, after observational studies, first advanced the idea of "hand hygiene" in medical settings.

The simple act of hand-washing is a critical way to prevent the spread of germs. Here's how Semmelweis, working in an obstetrics ward in Vienna in the 19th century, made the connection between dirty hands and deadly infection.

Benefits of cleanliness, symbolic and real The history of hand-washing extends back to ancient times, when it was largely a faith-based practice. The Old Testament, the Talmud and the Quran all mention han...