Introduction

Infectious Disease at the Millennium

As we approach the year 2000, one would have to be totally impervious to the lay media not to realize that serious problems confront us emanating from the microbial world. Some may view these developments with great alarm and fear that the final days are upon us. Indeed this issue might be construed by some as alarmist. Yet, the underlying theme of this issue is that forewarned is forearmed and that dentistry -- as a prominent member of the health care professions -- must face these issues; place them in perspective; attend to these problems where appropriate; and, above all, end any semblance of denial that such problems are real.

As an educator, I have come to realize that reality is not easily accepted and that many will deny as long as possible. Also, I find that many individuals do not have a firm grasp of the history of infectious disease. Prior to the advent of immunization, personal and civic hygiene, and antimicrobial agents, life was commonly brutish and short. Typhus, typhoid, diphtheria, whooping cough, smallpox, cholera, bubonic plague and yellow fever routinely devastated entire populations. Staphylococci and streptococci were the scourge of hospitals (as they are again today). The constant fear of our parents was the "dreaded disease of summer": poliomyelitis. Yet, today most of these infections have been eliminated from first world populations. How truly fortunate we are.

Yet as Murphy aptly cautions: "Optimism indicates that the situation is not clearly understood." So to place our current infectious disease situation in perspective in the limited space allotted, I prevailed upon three acknowledged experts in infectious disease to present their ideas on emerging diseases, hepatitis in its multiple forms, and microbial resistance to antibiotics particularly with reference to the oral cavity. Their efforts are followed by discussions on questions arising from the 1997 American Heart Association Prevention of Bacterial Endocarditis Guidelines, an update on patients who have taken fenfluramine/dexfenfluramine, and finally a review of the current status of antibiotic-associated Clostridium difficile colitis.

Having spent many hours talking with Dr. Jack Beierle on the topic of emerging and re-emerging infectious disease, I asked him to put this in writing as a general overview of the topic with special emphasis on what is and what can be done to manage these problems. This he has done admirably and, to those who might say this is not pertinent to dentistry, I must caution that infectious disease does not begin nor end at the dental office door.

I have known Dr. Michael Glick for many years and am most impressed with his knowledge of infectious disease and his expertise in treating medically complicated dental patients. He has provided us with a most expert and comprehensive discussion of hepatitis and its many etiologic agents, including the new TT virus. Surely hepatitis must be a major concern for us all.

After listening to a program by Dr. John Molinari on dental office infection control and being totally enthralled for hours, I asked him to present a general review of microbial resistance to antibiotics and was delighted with his suggestion that this be tailored to the oral cavity. He has done well on a topic (resistance of oral microbes to antimicrobial agents) that has received very little study due to limited finances and few investigators. We face an age of abundant use of chemicals to treat relatively innocuous diseases, and Dr. Molinari warns us of our past and present misguided use of antimicrobial agents.

Since the 1997 publication of the American Heart Association guidelines for the prevention of bacterial endocarditis, several members of the committee have answered questions regarding these recommendations put to us by dental practitioners and hygienists. Drs. Kathryn Taubert and Tommy Gage have assisted in putting our best advice answers to the questions on the printed page. These answers are not "official" from the AHA and are not intended to supplant the dentist's best clinical judgment in a given situation but seem reasonable and prudent to three who were present at the conception, gestation, and delivery of the AHA guidelines.

The discussion of the current status of the cardiac valvulopathy associated with fenfluramine and/or dexfenfluramine includes a review of all the published studies up to December 1998 (the deadline for submission to the Journal for these papers) and a discussion of the now operant three recommendations for the management of these patients. Also included is a discussion of the primary pulmonary hypertension caused by these agents, which is a greater short-term risk than the potential lifetime risk for endocarditis due to the valvulopathy. The table included in this paper should be very useful in a discussion with physicians who may not be aware of these recommendations.

Finally, the effort on antibiotic-induced Clostridium difficile colitis is the only update on this topic for dentistry since 1981, and it brings us a bit of good news. It appears that colitis in general and the dreaded pseudomembranous colitis associated with the community use of antibiotics is quite rare. This will be important if the widespread resistance of viridans streptococci to the penicillins seen today in hospitals spreads to the community as is likely. Clindamycin may return as the drug of choice in orofacial infections, particularly if such resistant streptococci become a community hazard. The downside is that Clostridium difficile is now a major pathogen in hospitals.

This issue of the Journal is intended as a strong dose of reality. It is not intended to frighten but to educate and motivate. It should put us beyond the learning curve of medicine on these topics. Hopefully, that is where we want to be.

Contributing Editor

Thomas J. Pallasch, DDS, MS, is a professor of pharmacology and periodontics at the University of Southern California School of Dentistry.