Advisers to the Nation on Science, Engineering, and Medicine

The National Academy of Sciences is a private, nonprofit, self-perpetuating society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare. Upon the authority of the charter granted it by the Congress in 1863, the Academy has a mandate that requires it to advise the federal government on scientific and technical matters. Dr. Bruce M.Alberts is president of the National Academy of Sciences.

The National Academy of Engineering was established in 1964, under the charter of the National Academy of Sciences, as a parallel organization of outstanding engineers. It is autonomous in its administration and in the selection of its members, sharing with the National Academy of Sciences the responsibility for advising the federal government. The National Academy of Engineering also sponsors engineering programs aimed at meeting national needs, encourages education and research, and recognizes the superior achievements of engineers. Dr. Wm.A.Wulf is president of the National Academy of Engineering.

The Institute of Medicine was established in 1970 by the National Academy of Sciences to secure the services of eminent members of appropriate professions in the examination of policy matters pertaining to the health of the public. The Institute acts under the responsibility given to the National Academy of Sciences by its congressional charter to be an adviser to the federal government and, upon its own initiative, to identify issues of medical care, research, and education. Dr. Harvey V.Fineberg is president of the Institute of Medicine.

The National Research Council was organized by the National Academy of Sciences in 1916 to associate the broad community of science and technology with the Academy’s purposes of furthering knowledge and advising the federal government. Functioning in accordance with general policies determined by the Academy, the Council has become the principal operating agency of both the National Academy of Sciences and the National Academy of Engineering in providing services to the government, the public, and the scientific and engineering communities. The Council is administered jointly by both Academies and the Institute of Medicine. Dr. Bruce M.Alberts and Dr. Wm.A. Wulf are chairman and vice chairman, respectively, of the National Research Council.

This report represents the integrated efforts of many individuals. The committee thanks all those who shared their insight and knowledge to bring the document to fruition. We also thank all those who provided information at our public meetings and who participated in our public sessions.

During the course of its deliberations, the committee sought assistance from several people who gave generously of their time to provide advice and information that were considered in its deliberations. Special thanks are due the following:

The committee is grateful to members of the National Research Council (NRC) staff who worked diligently to maintain progress and quality in its work.

This report has been reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise, in accordance with procedures approved by the National Research Council’s Report Review Committee. The purpose of this independent review is to provide candid and critical comments that will assist the institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:

Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations nor did they see the final draft of the report before its release. The review of this report was overseen by Dr. Norman Cheville. Appointed by the National Research Council, he was responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.

Control or eradication of important livestock diseases has been a top priority for the United States Department of Agriculture (USDA) throughout much of the previous century. Most efforts have involved mandatory national eradication programs. But mandatory programs bring a host of difficulties: they require a large program infrastructure, administration of indemnity programs, and constant scrutiny to uncover and eliminate loopholes. As most eradication programs near completion, attention is turning to other diseases that previously were not of sufficiently high priority to warrant mandatory control. These other diseases pose new challenges and may require novel approaches for control.

Johne’s disease (JD) is one such disease. Although its significance as an animal health and economic problem has been recognized for years, it is only now beginning to receive attention and prioritization for control. The United States Animal Health Association’s National Johne’s Disease Working Group has been leading the effort to provide national coordination and minimum standards for voluntary control, and USDA recently stepped in with the appointment of a national JD coordinator. Some of this recent attention is being driven by concern over the potential role of Mycobacterium avium subsp. paratuberculosis (Map), the causative agent of JD, in Crohn’s disease in humans. This issue warrants concern because it could affect the diagnosis and

treatment of Crohn’s disease and because it could change strategies for control of JD in livestock.

The USDA saw an opportunity to address this important issue and to facilitate progress in the control of JD in livestock. In August 2001, the Board on Agriculture and Natural Resources was asked to convene the Committee on the Diagnosis and Control of Johne’s Disease. The committee’s task was to review and synthesize the state of knowledge of JD in livestock, to evaluate current control plans, to critically assess the evidence for and against a causal relationship between Map and Crohn’s disease, and to provide recommendations for control and research.

The committee had a relatively short period in which to accomplish these ambitious goals, but I am pleased that its members approached the task with great enthusiasm and determination. The committee met twice in Washington D.C., and once in Hershey, Pennsylvania in conjunction with the annual meeting of the United States Animal Health Association. The latter meeting included a public workshop, where committee members heard from experts on JD and from a leading Crohn’s disease patient advocacy group. At its final meeting, the committee received an update on research into the link between Map and Crohn’s disease and a progress report on the Map genome project at the National Animal Disease Laboratory.

This report represents the outcome of many hours of hard work and spirited debate by committee members. I am grateful for their talent, dedication, intellectual integrity, and perseverance in the face of many challenges posed by our schedule and task. I am also very grateful to the Board on Agriculture and Natural Resources for the great care they took in assembling such a distinguished panel and for the opportunity to serve with them on this important committee. Finally, on behalf of the committee I would like to thank and acknowledge study director Tina Rouse and project assistant Cindy Lochhead for their outstanding dedication and persistence. Without their expertise, organizational skills, resilience, and resourcefulness, we could not have completed the task.

BRUCE A.RIDEOUT, Chair

Committee on Diagnosis and Control of Johne’s Disease