WHO officially released global warning on pandemic SARS disease.

Severe acute respiratory syndrome (SARS) is a viral respiratory disease of zoonotic origin caused by severe acute respiratory syndrome coronavirus (SARS-CoV or SARS-CoV-1), the first identified strain of the SARS coronavirus species severe acute respiratory syndromerelated coronavirus (SARSr-CoV). The first known cases occurred in November 2002, and the syndrome caused the 20022004 SARS outbreak. In the 2010s, Chinese scientists traced the virus through the intermediary of Asian palm civets to cave-dwelling horseshoe bats in Xiyang Yi Ethnic Township, Yunnan.SARS was a relatively rare disease; at the end of the epidemic in June 2003, the incidence was 8,469 cases with a case fatality rate (CFR) of 11%. No cases of SARS-CoV-1 have been reported worldwide since 2004.In December 2019, another strain of SARS-CoV was identified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This new strain causes coronavirus disease 2019 (COVID-19), a disease which brought about the COVID-19 pandemic.

The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of health". Headquartered in Geneva, Switzerland, it has six regional offices and 150 field offices worldwide.

The WHO was established on 7 April 1948. The first meeting of the World Health Assembly (WHA), the agency's governing body, took place on 24 July of that year. The WHO incorporated the assets, personnel, and duties of the League of Nations' Health Organization and the Office International d'Hygiène Publique, including the International Classification of Diseases (ICD). Its work began in earnest in 1951 after a significant infusion of financial and technical resources.The WHO's mandate seeks and includes: working worldwide to promote health, keeping the world safe, and serve the vulnerable. It advocates that a billion more people should have: universal health care coverage, engagement with the monitoring of public health risks, coordinating responses to health emergencies, and promoting health and well-being. It provides technical assistance to countries, sets international health standards, and collects data on global health issues. A publication, the World Health Report, provides assessments of worldwide health topics. The WHO also serves as a forum for discussions of health issues.The WHO has played a leading role in several public health achievements, most notably the eradication of smallpox, the near-eradication of polio, and the development of an Ebola vaccine. Its current priorities include communicable diseases, particularly HIV/AIDS, Ebola, COVID-19, malaria and tuberculosis; non-communicable diseases such as heart disease and cancer; healthy diet, nutrition, and food security; occupational health; and substance abuse. Its World Health Assembly, the agency's decision-making body, elects and advises an executive board made up of 34 health specialists. It selects the director-general, sets goals and priorities, and approves the budget and activities. The director-general is Tedros Adhanom Ghebreyesus of Ethiopia.The WHO relies on contributions from member states (both assessed and voluntary) and private donors for funding. Its total approved budget for 2020–2021 is over $7.2 billion, of which the majority comes from voluntary contributions from member states. Contributions are assessed by a formula that includes GDP per capita. Among the largest contributors were Germany (which contributed 12.18% of the budget), the Bill & Melinda Gates Foundation (11.65%), and the United States (7.85%).Since the late 20th century, the rise of new actors engaged in global health such as the World Bank, the Bill and Melinda Gates Foundation, the US President's Emergency Plan for AIDS Relief (PEPFAR) and dozens of public-private partnerships for global health have weakened the WHO’s role as a coordinator and policy leader in the field.