The "Morbidity and Mortality Weekly Report" of the Centers for Disease Control and Prevention reports that five people in Los Angeles, California, have a rare form of pneumonia seen only in patients with weakened immune systems, in what turns out to be the first recognized cases of AIDS.

The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgia.The agency's main goal is the protection of public health and safety through the control and prevention of disease, injury, and disability in the US and worldwide. The CDC focuses national attention on developing and applying disease control and prevention. It especially focuses its attention on infectious disease, food borne pathogens, environmental health, occupational safety and health, health promotion, injury prevention and educational activities designed to improve the health of United States citizens. The CDC also conducts research and provides information on non-infectious diseases, such as obesity and diabetes, and is a founding member of the International Association of National Public Health Institutes.The current Director of the CDC is Rochelle Walensky. The Director reports to the United States Secretary of Health and Human Services.

The Morbidity and Mortality Weekly Report (MMWR) is a weekly epidemiological digest for the United States published by the Centers for Disease Control and Prevention (CDC). It was originally established as Weekly Health Index in 1930, changing its title to Weekly Mortality Index in 1941 and Morbidity and Mortality in 1952. It acquired its current name in 1976. It is the main vehicle for publishing public health information and recommendations that have been received by the CDC from state health departments. Material published in the report is in the public domain and may be reprinted without permission. As of 2019, the journal's editor-in-chief is Charlotte Kent.As noted in the sequel, some single reports have evoked media interest also outside health and medical contexts. However, many reports are parts of series, providing consistent long-term statistics, and also indicating trend changes. Such a standing report section is the "Notifiable Diseases and Mortality Tables", which reports deaths by disease and state, and city for city, for 122 large cities. As another example, there are more than a hundred items about West Nile virus infections since the 1999 outbreak of the disease in the US. In 2001–2005, there were weekly updates of the WNV situation, during the warm seasons.