The World Health Organization (WHO), established in 1948, is the health arm of the United Nations. The WHO is dedicated to worldwide disease detection, prevention, and control, and also responds to disaster sites. In addition to fieldwork, the WHO performs research with the goal of understanding infectious disease and developing more effective treatments for it. The WHO participates in global programs aimed at increasing awareness about infectious disease, especially HIV, tuberculosis, and other such diseases.

The goal of the WHO, as set forth in the charter, is a state of complete health. The WHO has determined that health is not merely the absence of infirmity, but also incorporates mental and social well-being. To this end, the WHO travels all over the world not only on disease eradication missions but to improve nutrition, social conditions, and mental health for citizens world wide. Although the WHO deploys primarily in the developing world, officers of the organization can be found working in some first world nations as well.

The WHO implements many disease management protocols, in an effort to standardize disease response and make it more effective. Working with other organizations such as the American Centers for Disease Control, the WHO responds to outbreaks and also designs systems such as the Directly Observed Therapy Shortcourse (DOTS), a tuberculosis treatment program. Extensive WHO manuals on how to handle infectious disease allow officers to respond quickly and effectively all over the world.

The WHO is also active at refugee sites and disaster areas, implementing procedures to prevent the outbreak of disease and quickly responding in the event of infectious disease to contain, treat, and eliminate it. Frequently WHO officers are the first to be aware of rising political unrest and potential instability. WHO representatives report issues of concern to the main offices of the organization so that they can be acted upon. WHO staff can be found on battlefields, in refugee camps, and sorting through ecological disasters, creatingthe first line of defense for many nations.

The WHO collaborates with a variety of non-governmental organizations as well as government agencies in an effort to provide high quality health care to all global citizens. The WHO has the most extensive disease reporting and control network in the world thanks to these cooperative ties, and provides everything from low cost HIV medication to nutrition classes for expecting mothers. The WHO recognizes that the emergence of infectious diseases anywhere in the world is a threat to all citizens, and rapid response, treatment, and prevention are vital.