The World Health Organization (WHO) was established in 1948 as a specialized agency of the United Nations. The objective of WHO (www.who.int) is the attainment by all peoples of the highest possible level of health. “Health”, as defined in the WHO Constitution, is a state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity. WHO's main function is to act as the directing and coordinating authority on international health work.