Epidemiology
Epidemiology is the study and analysis of the distribution (who, when, and where) and determinants of health and disease conditions in defined populations.
Hygiene
Hygiene is a set of practices performed to preserve health. According to the World Health Organization (WHO), "Hygiene refers to conditions and practices that help to maintain health and prevent the spread of diseases." Personal hygiene refers to maintaining the body's cleanliness.
Medicine
Medicine is the science and practice of the diagnosis, treatment, and prevention of disease. Medicine encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness. Contemporary medicine applies biomedical sciences, biomedical research, genetics, and medical technology to diagnose, treat, and prevent injury and disease, typically through pharmaceuticals or surgery, but also through therapies as diverse as psychotherapy, external splints and traction, medical devices, biologics, and ionizing radiation, amongst others.
Medicine
But nothing is more estimable than a physician who, having studied nature from his youth, knows the properties of the human body, the diseases which assail it, the remedies which will benefit it, exercises his art with caution, and pays equal attention to the rich and the poor.
Voltaire, Dictionnaire philosophique portatif ("A Philosophical Dictionary") (1764), Physicians.
Medicine
Learn'd he was in medic'nal lore,
For by his side a pouch he wore,
Replete with strange hermetic powder
That wounds nine miles point-blank would solder.
Samuel Butler, Hudibras, Part I (1663-64), Canto II, line 223.
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