The
World Health Organization (
WHO ) is a specialized agency of the
United Nations (UN) that is concerned with international
public health. It was established on 7 April 1948, headquartered in
Geneva, Switzerland. The WHO is a member of the
United Nations Development Group. Its predecessor, the
Health Organization, was an agency of the
League of Nations. The constitution of the World Health Organization had been signed by 61 countries on 22 July 1946, with the first meeting of the
World Health Assembly finishing on 24 July 1948. It incorporated the
Office International d'Hygiène Publique and the League of Nations Health Organization. Since its creation, it has played a leading role in the
eradication of smallpox. Its current priorities include
communicable diseases, in particular
HIV/AIDS,
Ebola,
malaria and
tuberculosis; the mitigation of the effects of non-communicable diseases; sexual and reproductive health, development, and aging; nutrition, food security and healthy eating; occupational health; substance abuse; and driving the development of reporting, publications, and networking. The WHO is responsible for the
World Health Report, a leading international publication on health, the worldwide World Health Survey, and
World Health Day (7 April of every year). The head of WHO is
Margaret Chan.