Page images
PDF
EPUB

committee; that barrier techniques and universal precautions be followed for all patient care; and that continued emphasis be placed on disease prevention, professional and public education programs, and other primary public health measures. However, major ethical, medicolegal, social, and civil rights questions have been raised, and many questions remain unanswered. Therefore, we recommend that health care workers who are infected should voluntarily refrain from performing the subset of invasive procedures as defined by their professional organizations.

CANCERS

Question. Dr. Lõe, there are approximately 10,000 deaths each year from oral cancers and there hasn't been any significant improvement over the last 10 years. To what extent is your research agenda focusing on this issue? What role does NIDR have in this issue as compared to the role of NCI?

Answer. The new NIDR Long-Range Research Plan for the Nineties emphasizes the need to expand oral health research to include all the diseases and disorders that affect the mouth, the face, and the jaws. Approximately 30,000 individuals--primarily older Americans--are diagnosed with oral cancers each year, and, as has been noted, there are 10,000 deaths. Oral cancers constitute one of the deadliest forms of cancer known. Those who survive may face disfigurement from surgery, destruction of the salivary glands from radiation, and impairments in speaking, chewing, and swallowing.

For all these reasons, it is important to improve our ability to make early and accurate diagnoses and develop improved treatments. We are currently exploring ways to treat or reverse oral cancers with new drugs such as the retinoids and the beta carotenes (vitamin A analogues). Equally important are behavioral interventions to reduce known risk factors such as the use of tobacco and alcohol. Some studies are clarifying why the risk of oral cancer is worse when tobacco and alcohol are both used than when either is used alone.

At the basic science level, NIDR Intramural and extramural Investigators study the role of oncogenes and oral viruses such as the herpes and papillomaviruses in triggering the transformation of normal cells to malignant ones. To aid this research, NIDR-supported scientists have developed a novel method for growing human cancers in mice--traditionally an exceedingly difficult task. This model should facilitate all cancer research, enabling investigators to observe the growth and spread of any human tumor in the living animal.

NIDR and NCI Directors and staff met at the initiation of these new efforts and are working together to advance research on oral cancers, in this way maximizing resources. One activity will involve the joint development of a health promotion campaign to discourage young boys from using smokeless tobacco products. Baseball players will be used as role models.

IMPLANT TECHNOLOGY

$

Question. Dr. Löe, technology has been available for a number of years to fuse titanium with the bone and anchor new replacement teeth to this implant. What additional research is required in the area of implant technology?

Answer. Studies both in the United States and in Europe have confirmed that titanium implants can be successfully used to anchor permanent replacement teeth in patients missing all the teeth in one

or both jaws. There is also anecdotal evidence that, when several adjacent teeth are lost, they can be replaced by implant-supported partial dentures. On the other hand, there are essentially no data on the use of implants for single tooth replacements. Nevertheless, there is every reason to believe that such an approach would be more satisfactory than present-day crown and bridgework. The implant would be placed directly in the jaw bone and there would be no need to cap the adjacent teeth. Although additional clinical studies are needed, we believe that ultimately dental implants will become the treatment of choice for any and all missing teeth.

FLUOR I DATION AND PUBLIC HEALTH

Question. What is the Institute's position on a recently released report by the National Toxicology Program declaring that fluoridation of public water supplies is no danger to public health and is safe and effective in reducing cavities in affected populations?

Answer. The report in question was requested by the Assistant Secretary for Health, who appointed a subcommittee of his Committee to Coordinate Environmental Health and Related Programs (CCHERP) to conduct a major review of the risks and benefits of fluoride, This request followed the release of data from a National Toxicology Program experiment that found "equivocal" evidence of bone cancer in three male rats fed high dosages of fluoride in drinking water and one male rat fed a mid-high dosage. No bone cancers were found in female rats nor in male and female mice. The term "equivocal" means that the cancers could have occurred by chance alone.

The CCHERP report was released in February 1991 and is the most up-to-date and comprehensive of its kind. NIDR concurs with its findings, the most important being that there is no evidence that fluoride causes cancer of any kind in animals or human beings. This conclusion was based on animal experiments (such as the NTP study) and over 50 epidemiological studies, including an extensive review of cancer incidence and mortality in the United States by the National Cancer Institute. Another finding was that dental fluorosis has increased in nonfluoridated communities since the 1940s and may have increased in fluoridated communities. The cause is largely attributed to the wide availability of fluoride products and evidence of inappropriate and excessive use in some situations. Dental fluorosis (a condition that can range from a very mild staining of enamel to a more severe mottling and pitting of the surface) merits continued monitoring. but the fluorosis that has been reported is generally mild and more of a cosmetic than a health problem. The report affirms the safety and efficacy of water fluoridation, stating that it is the most cost effective and equitable (benefiting rich and poor alike) method of preventing tooth decay, and enumerates areas where additional research is needed.

Question. With the increasing use of fluorides in toothpastes and mouth washes, do you feel that a potential exists for fluoride overdoses in some populations?

Answer. It is important to note that dental fluorosis is a condition that affects developing teeth, so the issue raised concerns the oral health of children. NIDR does not recommend that mouth rinses be used by children aged 5 or under because they may swallow the rinse. Parents should also supervise toothbrushing in younger children to ensure that only a small amount of toothpaste is used on the brush. In terms of the population at large, we believe that it is important to document the incidence and prevalence of dental fluorosis and to monitor total fluoride intake from all sources in the environment, both in fluoridated and nonfluoridated areas, and among various age groups. This is one of the many important recommendations in the CCHERP report and in the NIDR Long-Range Research Plan for the Nineties.

NATIONAL INSTITUTE OF ALLERGY AND INFECTIOUS DISEASES STATEMENT OF DR. ANTHONY 8. FAUCI, DIRECTOR AND ASSOCIATE

DIRECTOR FOR HV RESEARCH

SUMMARY STATEMENT

Senator HARKIN. Now, we turn to the National Institute of Allergy and Infectious Diseases. Dr. Fauci, we have your budget request for $976.7 million, which is about 7.7 percent more than last year. I noticed that $459.3 million, or 47 percent, of your request is devoted to AIDS.

Again, we welcome you back and thank you again for your leadership of your Institute. And we would be delighted to hear your statement at this time. Dr. Fauci. Thank you very much, Mr. Chairman.

The National Institute of Allergy and Infectious Diseases is responsible for the conduct and support of basic and clinical research on infectious diseases, many of which cause extraordinary morbidity and mortality throughout the

world. One of these, as you mentioned, is the human immunodeficiency virus which causes AIDS.

In addition, we conduct and support research on the immune system which is the defense system of the body against the emergence of infections and certain neoplasms. I have come before this committee several times to discuss the research advances in these areas, and they have been truly extraordinary. However, these advances in biomedical technology have created a dilemma with their own new challenges. The public's expectation of what biomedical research can do to alleviate suffering and death caused by human diseases now clearly surpasses our available resources not only in research, but in health care delivery.

One way to bridge this gap is to prevent certain diseases before they occur, and this is particularly feasible with infectious diseases. Historically, vaccines have resulted in the saving of millions of lives and immeasurable financial costs. In this regard, the recent advances in technology have positioned us quite well to develop new vaccines for infections for which we thus far have no vaccines and more effective and safer vaccines for infections for which we already have existing vaccines.

In this regard, this past year basic and clinical research conducted by the NIAID in collaboration with the National Institute of Child Health and Human Development has resulted in the licensing of two new vaccines to protect infants against Haemophilus influenzae type b, the leading cause of bacterial meningitis in young children. This is an important advance, but just a start in NIAID's commitment to perform the basic and clinical research necessary to implement the children's vaccine initiative. The aim of this initiative is to develop an oral vaccine that provides lifelong immunity to the major diseases of childhood throughout the world. On another note, there has been a disturbing rise in morbidity and mortality due to asthma among inner city children, most of whom are minorities. NIAID recently announced eight awards to establish a network of centers to study this problem.

I can tell you more about this later on.

History in general and AIDS in particular has taught us that new and emerging microbes are a constant threat to our survival. NIAID is committed to remain at the forefront of research to strengthen our basic science alert system against this ever-present threat.

PREPARED STATEMENT In the area of gene therapy, which you have just heard about from some of my colleagues, NÍAID intramural scientists have re cently demonstrated that a factor secreted by cells called gamma interferon could dramatically restore the genetically determined defective capacity of white blood cells of individuals with chronic granulomatous disease to kill potentially lethal bacteria. This is an important breakthrough in our ability to modify cellular gene function as opposed to replacing absent or defective genes, a manipulation which is akin to gene therapy.

Finally, time does not permit in this opening statement to give a summary of our AIDS activities, but I look forward to discussing this with you in our question period.

Thank you, Mr. Chairman. [The statement follows:]

STATEMENT OF DR. ANTHONY S. FAUCI

Over the past four decades, the research mission of the National Institute

of Allergy and Infectious Diseases (NIAID) has evolved to encompass illness

sses

ranging from allergies to AIDS, from the common cold to exotic diseases that

devastate populations throughout the world.

These diverse areas of research

are all solidly grounded in the foundation of our Institute, which is basic

research on microbes that infect people and on the immune system that protects

us against these invaders.

This common theme underlles all of our efforts.

Today, even as biomedical researchers break new ground in immunology.

usher in the era of gene therapy, and design drugs that are highly specific

and effective against a wide range of infectious agents, such achievements

create a new challenge. The public's expectations of what biomedical research

can do to alleviate suffering and death caused by human diseases far surpasses

our available resources.

How then can NIAID best employ its sophisticated technologies to fulfill

its mission of improving public health?

The most effective way to narrow the

growing gap between expectations and available resources is to prevent

diseases before they occur.

In the area of infectious diseases, this is best

achieved through vaccines.

Our foundation of basic research and our accomplishments in vaccine

development make NIAID uniquely positioned to lead the renaissance in

vaccinology that is being realized in the decade of the 1990s. Historically.

vaccines have dramatically decreased or even completely eliminated infectious

diseases that have taken heavy tolls on past civilizations.

A classic example

is the complete eradication of the scourge of smallpox from the world.

None theless, we have realized only a fraction of the full potential of

vaccines to prevent a wide array of Infections that cause considerable

morbidity and mortality throughout the world.

Over the past several years.

natural products and synthetic peptides of organisms and, most recently.

recombinant DNA products have largely replaced whole killed or attenuated

organisms that have traditionally been used to make vaccines.

These newer

approaches have resulted in more specific and potentially less toxic vaccines.

Something more theoretical, but with considerable potential, is the

concept of Intracellular immunization, which employs a form of gene therapy to

« PreviousContinue »