A History of MMWR

Frederic E. Shaw, MD, JD1

Richard A. Goodman, MD, JD2

Mary Lou Lindegren, MD3

John W. Ward, MD4

1Public Health Surveillance Program Office, Office of Surveillance, Epidemiology and Laboratory Services, CDC, Atlanta, Georgia

2National Center for Chronic Disease Prevention and Health Promotion, CDC, Atlanta, Georgia

3Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee

4Division of Viral Hepatitis, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, CDC, Atlanta, Georgia

Corresponding author: Frederic E. Shaw, MD, JD, Public Health Surveillance Program Office, Office of Epidemiology, Surveillance and Laboratory Services, CDC, Mailstop E-97, 1600 Clifton Road, N.E., Atlanta, GA 30333;Telephone: 404-498-6364; Fax: 404-498-0585; E-mail: fxs6@cdc.gov.

MMWR was established to disseminate the results of public health surveillance and owes much of its existence to the founder of modern surveillance, William Farr (1807--1883). In 1878, under the sway of Farr, Lemuel Shattuck, and other pioneers of surveillance, the U.S. government created the first precursor of MMWR and entered the business of publishing surveillance statistics. Farr's influence touched MMWR again in 1961 when one of his adherents, Alexander D. Langmuir (Figure 1), brought MMWR to Atlanta and CDC from a federal office in Washington, D.C. (1). Since its beginnings, MMWR has played a unique role in addressing emerging public health problems by working with state and local health departments to announce problems even before their cause is known, rapidly disseminating new knowledge about them weeks or months before articles appear in the medical literature, and publishing recommendations for their control and prevention. MMWR has played this role time after time---the discovery of Legionnaires disease in the 1970s, AIDS and toxic-shock syndrome in the 1980s, hantavirus pulmonary syndrome in the 1990s, and severe acute respiratory syndrome (SARS) in the 2000s. At the same time, MMWR also has reported on nearly all the major noninfectious public health problems of the day---environmental emergencies, chronic diseases, injuries, and new public health technologies. To a great extent, the history of MMWR is the history of disease and injury prevention and control in the United States (Table 1).

MMWR's Precursors

MMWR's history began on April 29, 1878, when Congress passed the National Quarantine Act. The Act required the Surgeon General of the U.S. Marine-Hospital Service (later to become the U.S. Public Health Service [PHS]) to collect reports from U.S. consular officers on the sanitary condition of vessels departing for the United States and to give notice of these vessels to federal and state officers through weekly abstracts (2). This mandate resulted in The Bulletin of the Public Health (Figure 2), the first precursor of MMWR. The Marine-Hospital Service published the first issue of the Bulletin on July 13, 1878. It ran just six paragraphs and described cases of cholera, smallpox, and yellow fever in Key West, Florida; Cuba; and Malta (3). In 1878, a great yellow fever epidemic was raging in the Mississippi Valley, eventually to claim 20,000 lives (4), and a reader of these early reports can feel its deadly effects. On August 24, 1878, the Bulletin published a telegram from Dr. Booth, the Marine-Hospital Service officer at Vicksburg, Mississippi: "I am sick; impossible to procure accurate data." A week later, the Bulletin's report from Vicksburg said, "Dr. Booth, in charge of the patients of the Marine-Hospital Service, died the 27th."

On June 2, 1879, Congress repealed the earlier reporting provisions, and the Bulletin ended after just 46 issues, leaving dormant the reporting of surveillance statistics by the federal government. It reawakened with the advent of a new publication in 1887, The Weekly Abstract of Sanitary Reports, which continued the numbering of the Bulletin. Issue number 47 appeared on January 20, 1887. Like the Bulletin, the new publication contained communicable disease reports from foreign ports and the U.S. states, including a mortality table of U.S. cities. The Weekly Abstract also contained occasional narrative reports on public health topics. It reached 1,800 readers and was, in its editor's words, "greatly appreciated not only by quarantine officers, but steamship companies, merchants, and the press" (4).

On January 3, 1896, The Weekly Abstract became Public Health Reports, a journal that is still published today as the official journal of PHS. Initially, Public Health Reports looked a great deal like the Weekly Abstract, but in time Public Health Reports took the form of a full-fledged scientific journal and published important observations and research on communicable diseases and epidemiologic and laboratory investigations, plus such items as municipal ordinances, state legislation, and public health legal opinions. The PHS published Public Health Reports weekly until 1952, when it became a monthly publication, and in 1974, a bimonthly. By 1913, a motto of public health surveillance principles was appearing on the masthead of the publication's pages reporting notifiable diseases: "No health department, State or local, can effectively prevent or control disease without knowledge of when, where, and under what conditions cases are occurring." This motto appeared in Public Health Reports for 39 years (5).

Until 1942, morbidity statistics were collected, compiled, and published in Public Health Reports by the PHS Division of Sanitary Reports and Statistics. In that year, this responsibility was transferred to the Division of Public Health Methods, and in 1949, to the National Office of Vital Statistics (NOVS),* another PHS agency (5). Morbidity and mortality statistics continued to be published in Public Health Reports until January 20, 1950, when they were transferred to a new NOVS publication called the Weekly Morbidity Report, the first publication to look like the modern-day MMWR. In 1952, NOVS changed the name of this publication to the Morbidity and Mortality Weekly Report.

Bringing MMWR to CDC

In 1960, CDC was only 14 years old; it had been organized in 1946 in Atlanta as an outgrowth of the federal agency, Malaria Control in War Areas (6). In 1949, Langmuir came to CDC, then known as the Communicable Disease Center, to head the epidemiology branch. Early in his career, Langmuir had worked at local and state health departments and had recognized the crucial importance of vital statistics and public health surveillance. During his early years at CDC, he noticed that the staff at NOVS who received, compiled, and reported federal surveillance statistics were not trained in epidemiology and, as a colleague later said, "had no obligation---or, apparently, inclination---to analyze data rapidly and act on the implications" (7). Langmuir became determined to move the surveillance function and its accompanying publication, MMWR, to CDC's epidemiology branch.

To counteract ambivalence about the transfer at both NOVS and CDC (7; David J. Sencer, personal communication, August 10, 2010), Langmuir worked hard to persuade his superiors that the job of disease surveillance fit better into CDC's mission than NOVS's. He enlisted help from colleagues in Washington and at CDC. David J. Sencer, the future director of CDC who was then working at the Bureau of State Services in Washington, weighed in on Langmuir's side, as did the Surgeon General's Study Group and a task force that had been appointed to consider the transfer. As Langmuir later said in an interview, "[After] all sorts of pulling out teeth by the roots without anesthesia and all kinds of internal frictions, ... on July 1st, 1960, we had the obligation, formal duty, of issuing the weekly morbidity and mortality report" (8). The Department of Health, Education, and Welfare formally approved the transfer on September 30, 1960. To make MMWR functional at CDC, the Department transferred a budget of $16,500 and 1.5 employee positions to CDC (David J. Sencer, personal communication, August 10, 2010).

Langmuir named E. Russell Alexander as the first CDC editor of MMWR but worked tirelessly on MMWR himself (Table 2). During MMWR's first 9 years at CDC, Langmuir gave MMWR his highest priority, labored over the text of each article, and approved gradual improvements. Over time, Langmuir began using MMWR to change practices in state and local health departments and clinicians (8). To make state and local health departments' work more prominent, he required that authors of MMWR articles from state and local health departments be listed first and that CDC authors be listed only by the name of their program and not individually. Langmuir also experimented with the use of an editorial note to accompany the factual reports.

The 1970s and 1980s

A turning point in the history of MMWR was Langmuir's appointment of Michael B. Gregg as MMWR editor in 1967 (Figure 3). Gregg became the longest-serving editor in MMWR's history and exerted a major effect on MMWR's personality, language, and scientific standards. Gregg had come to CDC in 1966 and had worked under Langmuir (9,10). Soon after Langmuir appointed him as MMWR Editor, Gregg applied his literary skills to MMWR, editing each article carefully to ensure that it was written in clear, compact English and that it stuck to the epidemiologic findings (11; Anne Mather, personal communication, August 17, 2010).† During the 1970s, Gregg developed the editorial note into a consistent and valuable feature of each article; he took special pride in these notes, which he observed were the most-read part of MMWR articles and gave CDC a chance to point out the implications of the facts presented (11). The editorial note became the place where each MMWR report answers the "so what?" question: what actions should be taken by readers (e.g., medical personnel, state and local health departments) as a result of the information in the report.

One of Gregg's most enduring contributions to MMWR was to persuade the National Library of Medicine to include content from MMWR in the Index Medicus (10). Beginning in 1981, inclusion there would mean that all reports published in MMWR would forever become part of the indexed medical literature. Through Gregg's steady improvements, gradually MMWR became required reading at state and local health departments and medical offices and within the health press.

In early May 1981, Gregg received a telephone call from Wayne Shandera, an Epidemic Intelligence Service (EIS) Officer assigned to the Los Angeles County Department of Health (12). Shandera described five cases of Pneumocystis carinii pneumonia in young men. The five men had in common that they were previously healthy and had had sex with other men. Pneumocystis pneumonia was seen mainly in persons with cancer or other immunosuppressive conditions, and a group of five cases in otherwise healthy young men was highly unusual. The attending physician who had treated four of the men, Michael Gottlieb, wanted to publish the cases in a medical journal but knew that would take months (6). Shandera asked Gregg whether he would be interested in publishing a description of the cases in MMWR. Gregg did not know quite what to make of the cases but asked Shandera to submit a report to MMWR (12). After consulting with colleagues at CDC, Gregg published the report in MMWR on June 5, 1981 (13) (Figure 4). Immediately after the article appeared, clinicians across the country who had seen similar patients realized the connection to the Los Angeles cases (12). Recognition of the AIDS epidemic had begun. The first AIDS article in the peer-reviewed medical literature appeared 4 months later (14).

Until the mid-1980s, CDC provided a free print subscription by airmail to anybody who requested one, and circulation rocketed from approximately 6,000 in 1961 to 80,000 in 1981 and 120,000 in 1983. In 1982, the cost of MMWR printing and distribution came under scrutiny, and CDC director William Foege was obliged to take "a painful departure from our tradition" (15) and notify MMWR readers that CDC would no longer provide unrestricted free distribution. Overnight, free mailed subscriptions from CDC dropped from 120,000 to about 12,000. The drastic reduction in free distribution prompted complaints from subscribers and the medical community. Foege, Gregg, and colleagues at CDC talked with leaders in the medical press about how to fill the gap. On February 24, 1983, the editor of the New England Journal of Medicine, Arnold S. Relman, announced that the Journal's parent organization, the Massachusetts Medical Society, would begin reprinting MMWR and selling subscriptions at $20.00 per year (16). That arrangement, at a current rate of $189 per year, remains in effect, and the Society continues to reprint all series of MMWR for approximately 5,500 paid subscribers (Ann Russ, Massachusetts Medical Society, personal communication, September 7, 2010). In March 1983, George D. Lundberg, the editor of the Journal of the American Medical Association (JAMA), announced that JAMA would begin publishing weekly in its pages lead articles from MMWR (17). That arrangement, too, continues today.§

The 1990s

Gregg stepped down as MMWR editor in 1988 and was succeeded by Richard A. Goodman. During Goodman's tenure as editor, two of MMWR's priorities were to expand its content and turn the articles toward specific public health actions. By 1990, MMWR's circulation had rebounded to 45,000--50,000 (7), mostly through the Massachusetts Medical Society. The national news media were covering CDC's activities closely, and several times each month MMWR articles were the source of national news stories. By the early 1990s, MMWR had published hundreds of articles on the burgeoning AIDS epidemic. One of the most influential was an article published July 27, 1990, about transmission of HIV to patients by a dentist in Florida (18), the first documented instance of HIV transmission through a medical procedure. Publication of this report received enormous attention by the media, dramatically underscoring the sway of CDC and MMWR over public health information (Richard A. Goodman, personal communication, August 18, 2010).

By 1990, MMWR had become a series of four publications: the MMWR weekly, the annual Summary of Notifiable Diseases, the CDC Surveillance Summaries, and Supplements. The Surveillance Summaries series had been created in 1983 by Stephen B. Thacker, the director of the CDC surveillance office from which the MMWR emanated, to centralize and promote surveillance activities of CDC programs (Stephen B. Thacker, personal communication, August 17, 2010). Previously, CDC surveillance data had been published and distributed by each individual CDC program. The rising prominence of MMWR placed more pressure on authors inside and outside CDC to publish their findings quickly in MMWR. EIS Officers had a new requirement to submit reports to MMWR as part of their CDC training. Submissions to MMWR soared.

In the late 1980s, MMWR determined that just one type of report consumed approximately one fourth of all text pages in the MMWR weekly: official vaccination recommendations from CDC's Advisory Committee on Immunization Practices (19; Richard A. Goodman, personal communication, August 18, 2010). To alleviate the problem and to accommodate demand for space for reports of epidemiologic field investigations and other work, MMWR created the Recommendations and Reports in 1990. Since then, the Recommendations and Reports series has been MMWR's main vehicle for publishing the full spectrum of official CDC recommendations, from the diagnosis of tuberculosis to the vaccination recommendations of the Advisory Committee on Immunization Practices.

The 1990s also marked MMWR's first foray into electronic publishing. Since the mid-1980s, CDC had made MMWR available to state and local health departments and other entities through dedicated electronic systems operated through telephone lines (20). In 1992, MMWR content became available through a file transfer protocol (FTP) server. However, these systems were often expensive and difficult to use. Beginning in 1993, CDC began to convert MMWR into electronic format and increase its availability through the Internet. In January 1995, the publication made its editions available both through FTP and the World-Wide Web (21; T. Demetri Vacalis, personal communication, August 11, 2010). The new Internet distribution quickly had an unanticipated benefit. In 1995, MMWR had never missed publishing a weekly issue (a record that remains true today). In November of that year, 10 months after MMWR instituted electronic distribution, the federal government shut down all but emergency functions because of a budget impasse between the President and the Congress. For its November 17, 1995, edition, MMWR had to delay printing the weekly issue, but still released MMWR on time through its new electronic capability (22).

In June 1996, on the occasion of CDC's 50th anniversary, MMWR published a special issue featuring CDC's history and the evolution of reporting public health data (23). In 1999, also in recognition of CDC's 50th anniversary, MMWR published a compendium of selected reports that had appeared during 1961--1996 on such topics as smallpox, Legionnaires disease, HIV/AIDS, and other major public health events covered in MMWR (24).

The 2000s

The events of September 11, 2001, and the subsequent anthrax attacks brought a major focus on bioterrorism and emergency preparedness to CDC and MMWR. During the 2000s, other public health events also affected the path of MMWR, including the advent of SARS, the expansion of West Nile and emergence of monkeypox virus infections in the United States, and greater national aspirations for the control of influenza epidemics. At the same time, MMWR was obliged to cope with a building maelstrom in the medical publishing world spawned by the explosive growth of the Internet.

Goodman stepped down as editor in 1998 and was succeeded by John W. Ward. One of Ward's first jobs was to find a way for MMWR to celebrate the coming new millennium. Jeffrey P. Koplan, CDC director during 1998--2002, came up with the idea of a series on the 10 great achievement of public health in the previous century. MMWR began publishing the series in April 1999 (25), and the articles became among the most cited ever published by MMWR.

The new millennium was only months old when the attacks of September 11 occurred, followed in October by the intentional releases of anthrax spores. MMWR published its first article on the anthrax attacks on October 12, 2001 (26,27), and for weeks published updates on the epidemiologic investigation and recommendations. In March 2003, when SARS erupted around the world, MMWR began to publish articles on the epidemic, updating the number of cases reported to the World Health Organization, the number of deaths and related public health alerts and information (28).

By 2002, most MMWR subscribers received the publication by e-mail, which had supplanted postal letters as the main method of communication between CDC and state and local health departments. MMWR's e-mail circulation was approximately 30,000, which when combined with the ongoing print subscriptions mailed by CDC and the Massachusetts Medical Society, gave a total circulation of about 50,000.¶ The occurrence of so many public health emergencies during the early 2000s brought the realization that, during critical events, MMWR could no longer wait until the routine weekly issue on Friday to send critical information to readers (John W. Ward, personal communication, August 4, 2010.). Before 2002, only once in its history had MMWR published an issue on a day other than Friday, in January 1977 to announce CDC's discovery of the bacterium that caused Legionnaires disease (David J. Sencer, personal communication, August 10, 2010). On September 13, 2002, MMWR published its first "Dispatch," a new form of urgent report that could be emailed to readers at any time, day or night (29).

The early 2000s brought other changes as MMWR strove to adapt to the rapidly changing communications world (Mary Lou Lindegren, personal communication, August 9, 2010). The MMWR series became more Web-centric, adapting its editorial policies to match Web-based publication. In 2001, MMWR's graphical appearance changed from its longstanding 6- by 8-inch black-and-white format to a new 81/2-inch by 11-inch two-color format. To match the scope of CDC's work, MMWR's content became more diverse (e.g., reviews by CDC's Guide to Community Health Services, more reports on chronic disease and injuries, and a new one-page graphical snapshot of key public health statistics called QuickStats, produced by CDC's National Center for Health Statistics). In 2002, CDC contributors to the weekly were for the first time listed by name.

Ward stepped down as the MMWR editor in 2005 and was succeeded by Mary Lou Lindegren. In 2005, both Ward and Lindegren believed that MMWR needed an advisory board to provide independent advice to the MMWR editor. After 2 years of planning, the MMWR Editorial Board met for the first time in June 2006, chaired by William L. Roper, a former CDC director. Also during the mid-2000s, in response to findings from a CDC committee on the quality of evidence used in CDC recommendations, for the first time MMWR listed explicit guidelines for making official recommendations in its pages and required contributors to state more clearly the evidentiary basis of recommendations. MMWR also revamped its production process; added new technologies such as RSS feeds; and developed new content, such as a series of perspective reports from past CDC directors and a compendium celebrating 60 years of public health science at CDC (30). MMWR also increased its role in documenting the impact of global public health initiatives (e.g., polio eradication, measles eradication, global HIV control efforts), and copublished many articles with the World Health Organization's Weekly Epidemiological Record.

Lindegren was succeeded by Frederic E. Shaw in 2007 and MMWR added its first deputy editor in 2009.** Beginning October 2006, two new podcasts, broadcast in English and Spanish, became the sixth component of the MMWR series. They were MMWR's first foray into products for lay audiences. MMWR also revamped the graphical format of the series (the first revision since 2001), added new report types to the weekly (e.g., CDC's Public Health Grand Rounds, mini-articles that appear under the header, "Notes from the Field"), and instituted an MMWR presence on Facebook and Twitter. In 2010, MMWR also implemented a suggestion from CDC's new director, Thomas R. Frieden, by inaugurating the publication of "Vital Signs," a new coordinated CDC communication effort anchored by scientific articles in MMWR (31). In April 2009, the worldwide outbreak of pandemic influenza A (H1N1) (then called swine influenza H1N1) began; MMWR reported the first two cases on April 21, 2009 (32), then published rapid-fire articles on the pandemic, including MMWR's first published articles in Spanish. By the end of 2010, MMWR had published 45 articles on various aspects of the pandemic.

By 2007, the technology used by MMWR to distribute the publication by e-mail had become antiquated. In February 2009, MMWR switched to a new Web-based system that made subscribing to MMWR easier. This change, combined with a huge public interest in 2009 pandemic (H1N1), vaulted MMWR's electronic circulation from approximately 50,000 in 2007 to 100,000 in 2010. By August 2010, with the remaining print subscription base of about 13,000, MMWR's total circulation had reached almost 115,000, near the level at which it stood before the budget cuts of 1982. Together with articles reprinted to JAMA's subscribers, approximately 1 million monthly visits to the MMWR website, podcast downloads of 50,000 per week, and MMWR followers on Facebook and Twitter, by its 50th anniversary at CDC in 2011, MMWR was seen by a bigger and broader audience than ever before.

The Future

When the Internet began to emerge into common use in the early 1990s, no one could have imagined the revolutionary effects it would have on medical and public health communications. One effect on MMWR has been to create competitors for MMWR's traditional mission of bridging the gap between immediate news media reports of public health events and later scientific publication (5). Today, medical journals are able to publish scientific articles more quickly than before through electronic means. During the recent outbreak of pandemic (H1N1) influenza, The New England Journal of Medicine electronically published information about the epidemiology of the disease within just a few days of data collection (33).

In 1961, and for decades afterwards, MMWR was the only way for CDC to mass-disseminate scientific information rapidly about public health events. Today, several other electronic channels exist at CDC for rapid communications about public health events: Epi-X (an electronic communication system for public health officials), the Health Alert Network (HAN), the Clinician Outreach and Communication Activity (COCA), satellite or Internet-based conferencing, mass e-mails, and informal posting on the Web. During the recent influenza pandemic, CDC relied on all these channels to communicate epidemiologic data and recommendations to state and local health departments and the medical community and relied especially heavily on informal postings on the Web. Ten years from now, a historian who wishes to trace CDC's work on the pandemic will consult MMWR's archives, but also will be obliged to consult electronic materials on the Web and other channels, if they are still accessible.

Despite these pressures, MMWR's traditional role continues. Informal Web postings, attractive as they might be, do not receive the rigorous review and editing that MMWR content does, nor are they indexed in MEDLINE, something that authors still believe is important. Rapid public releases to the news media or to health-care providers generally do not contain the kind of detailed scientific information sought by public health and medical audiences. Medical journals, although much more nimble than ever before, cannot publish state or federal public health investigations within hours, nor replace MMWR's central role as the official voice of CDC, nor publish lengthy official CDC recommendations or surveillance statistics. These functions will remain unique to MMWR into the future. As the future unfolds, new roles for MMWR will continue to appear as they have over the past 50 years, and MMWR will evolve to meet the needs of public health.

Acknowledgements

This report is based on helpful interviews, editorial assistance, and reviews by Karen L. Foster, Suzanne M. Hewitt, Anne Mather, Teresa F. Rutledge, Myron G. Schultz, David J. Sencer, Stephen B. Thacker, and T. Demetri Vacalis.

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