Until the first part of the 20th century, health was defined as the absence of disease and was
measured in terms of morbidity and mortality. This simple definition of health was rejected in 1948
with the expansion of the concept of health by the World Health Organization (WHO), defining it as
“a state of complete physical, mental and social well-being and not merely the absence of disease
or infirmity” (World Health Organization 1948).
