It is a distinct honor to be with you this evening and have the opportunity to share my thoughts and observations with you as we move from a remarkable century into the next millennium. While it is human trait to look to the future with optimism, the millennium offers us license to dream more expansively. The tremendous accomplishments in medicine in the last century will enable us to achieve even greater success in the coming century.

The development and widespread us of modern vaccines is one of the successes that we can be most proud of, for it is trulymiraculous. While there is likely to be lots of talk about the now famous Y2K bug as we reach the turn of the century, many of the other bugs that that have plagued mankind since the last millennium — such as polio, measles, congenital rubella, meningitis, and tetanus — are no longer at center stage. If you haven't seen it already, I encourage you to have a look at the April 2 issue of the MMWR.

This issue, part of CDC's countdown to the millennium, is the first of a series of features of the "Top 10" greatest achievements in public health in this century. In it you will find that compared with the "pre-vaccine era" we have reduced each of the vaccine preventable diseases by more than 95%, in some cases like smallpox and polio, eliminated them entirely. To give the global eradication of smallpox its proper tribute, consider for a moment that this occurred throughoutthe entire world population: urban and rural, male and female, rich and poor, all nations, and yes, all races.

The Hib story

I'd like to highlight just one remarkable vaccine success story because it is largely untold — the Hib story. Just over a decade ago Haemophilus influenzae type b ("Hib") was the most common serious bacterial infection in children less than five years of age. This infection, with clinical manifestations of meningitis, epiglottitis, pneumonia and bloodstream infection affected one in every 200 children, approximately 20,000 young children each year. Despite the best medical care at the nations best hospitals, one in 20 would die. Up to 30% of those who survived suffered the long-term residual effects of the infection such as seizure disorders, mental retardation and hearing loss. The first generation Hib vaccine was introduced in 1985 followed a few years later by more effective vaccines that could be administered to children as young as 2 months of age. In 1998, barely a decade later, there were just 54 reported cases of this diseases in the United States, down from 20,000! Again, this occurred all over the country, in all states, in all communities and in all races. The decline has been so drastic that there is concern in medical schools and teaching hospitals that young pediatricians in training may not acquire sufficient experience in learning to care for patients with bacterial meningitis since this disease has become so rare. This is public health and clinical medicine at its absolute best — truly a miraculous accomplishment.

The Promise of Technology

At the same time, we are now reaping the benefits of our investments in the science of immunology, genetics and molecular biology. There is an exponential growth in the number of approaches to vaccine development. The technology that is being considered was unimaginable just a decade ago and offers tremendous promise to both simplify the immunization process and provide protection against an increasing number of diseases. For example, new delivery systems such as nasal spray vaccine (influenza) and even edible vaccines grown in plants such as potatoes and bananas may one day allow us to shift away from "shots." We are also hopeful that the development of combination vaccines will help to simplify the increasingly complex childhood immunization schedule.

The Challenges Ahead

Yet despite this tremendous success and the promise of a new era of vaccines, challenges still remain.

Of the many that face us, there are two special concerns of mine that I would like to share with you.

1. A persistent disparity among vaccine utilization and the incidence of vaccine preventable diseases in many sectors often referred to as "pockets of need" and,
2. A decline in confidence about the need for and safety of our vaccines that has emerged as vaccine-preventable diseases have been so effectively controlled.

Eliminating Health Disparities

As I mentioned earlier, surveys of vaccine coverage among infants and children in the US convincingly demonstrate that the achievement of a historic high rate of vaccine utilization has been accompanied by the decline in vaccine-preventable diseases. Nationally we have made great strides in nearly all sectors of the population. However, differences in age-appropriate coverage rates persist between demographic groups. A recent analysis shows that these differences are accounted for by poverty, not race or color. While the full explanations for this disparity are not clear, we do know that inner-city children who are poor and members of minority group are less likely to be up-to-date in their immunizations compared with white children in the same community. This highlights our continuing need to focus on this part of the problem and better understand the precise factors that determine how poverty is associated with undervaccination. Such an analysis will help to develop and guide appropriate interventions. Before I leave this point, it is important to caution you that national statistics can often mask vast differences occurring at the community level. I'm sure that this evening we will hear about some of the local "pockets of need" and how these needs are being addressed.

In striking contrast to our progress in childhood vaccines, our outreach to the nation's older population has been deficient and their health status suffers as a result. Our immunization programs for adults, the elderly and those with conditions that put them at high risk of vaccine-preventable infections and their complications have not been as effective as our infant and childhood immunization programs. As Surgeon General Satcher has noted, vaccine preventable diseases continue to occur in people aged 65 or older, the fastest growing age segment of our population. In this group, the reduction of both influenza and pneumococcal disease has been hindered, in part, by low vaccine utilization. Each year an estimated 45,000 adults died of influenza, pneumococcal disease, hepatitis B infection and their complications. Most striking is the disproportionate burden of these diseases in minority and underserved populations.

Yes, despite our progress, challenges remain in the effective delivery of a range of prevention services — and immunizations rank at the top of that list. I am glad to see that this is getting the attention it deserves with the goal of the elimination of health disparities in the nation's plan for Healthy People 2010. With a concerted effort I believe that the goals for 2010 can be met.

Decline in confidence in vaccines

There is another challenge that I find much more worrisome — the decline in public confidence about our immunizations. Perhaps this is THE challenge for the immunization community at the new millennium. As I told the National Immunization Conference participants in Atlanta last year, it is the ultimate irony that as we celebrate the prevention of epidemics of diseases that just a few generations ago sent fears through the community — meningitis, polio, diphtheria, congenital rubella, measles — we must also acknowledge the growing misconception that vaccines cause more harm than good.

As vaccine-preventable diseases have disappeared it appears that there are a growing number who are calling into question the need for continued use of vaccines. Allegations that vaccines may cause disease provide another reason for some to question the value of immunizations. As you well know, scientific inquiry is guided by answering the questions generated by a research hypothesis. Now it appears that hypothesis becomes "fact" merely because it is being pondered. Worse, it remains as "fact" even when studies are conducted and the results are negative.

Example: MMR and autism

For example, last year an investigator in England published his hypothesis that the MMR vaccine is the cause of inflammatory bowel disease and autism. Part of this theory, though unsubstantiated, was that the three antigens — measles, mumps and rubella — given together somehow are at the heart of the problem. As you might guess, a study like this published in the Lancet drew a lot of attention in the press and generated substantial concern among parents. Not surprisingly there was a decline in the acceptance of the vaccine despite a thorough review of the science by the British Medical Research Council. Unfortunately, the publicity surrounding this event received more attention than did the final review. While efforts by the medical community to present the facts have nearly restored MMR uptake levels to their previous levels, for many in the community this episode raises a question that lingers about this vaccine, and perhaps about immunization in general.

This is the information age and events like this anywhere in the world can have an effect anywhere else. Two weeks ago a bill was introduced into the Louisiana legislature on behalf of a constituent with an autistic child. This bill is intended to remove MMR vaccine from the childhood immunization schedule and replace it with individual vaccines — first measles, then mumps then rubella — delivered separately over a three year period. There is absolutely no scientific evidence to support the effectiveness of such an approach. This "schedule" would greatly complicate the immunization of the children of Louisiana who would remain susceptible to these diseases for a much longer period of time. And, the purchase and administration of these individual vaccines would not be covered by federal programs and could cost the taxpayers of Louisiana an additional $6-8 million each year. Despite all of this, the bill was passed out of Subcommittee in the Louisiana House by a margin of 7 to 2.

A booklet put out by the CDC, now available on their web site, "6 Common Misconceptions about Vaccines and how to respond to them" documents but a few of the concerns that have emerged recently. I'd like to highlight a few of these common misconceptions:

1. The diseases were on the decline long before the introduction of vaccines.
2. The diseases are gone, so we no longer need vaccines, and
3. Vaccines "overload" the immune system and increase the risk of side effects.

I wonder what concerns that you are hearing from your patients? I ask you this because over the past year and a half, I have been part of a special project of the Infectious Diseases Society of America and the Pediatric Infectious Diseases Society. This effort, the National Network for Immunization Information (NNii), came about because we heard from an increasing number of clinicians that were being challenged by their patients on issues like these. Equipped with newspaper clippings, web site printouts, conversations in Internet chat rooms, books from the shelves of the local bookstore, and "news" stories on local and national television, doctors across the country were being faced with an erosion in confidence about our immunization system.

With full support by a grant from the Robert Wood Johnson Foundation that preserves our independence by not allowing funding from either vaccine manufacturers or the government, this project is designed to better understand how we have gotten to this point, the sources of concern, and most importantly to develop an effective strategy to restore the public's confidence around this issue. Who would have imagined that we would come to a point when there was a serious debate about whether vaccines are causing more harm than good?

We have begun this project by going out and listening to the concerns. We've conducted focus groups across the country and that information has helped us to develop a national survey to understand the magnitude of concerns like these.

From these results, we will be able to fully develop our program, but there are two things that are quite clear to us even at this early stage of the project.

First, patients and parents continue to tell us that despite the many places they turn to for information, the vast majority continue to rely on their doctor to help them reach an informed decision. We need to ensure that when a patient comes to our clinic or office that we address their questions and concerns. For if we don't help them reach an informed decision, they are likely to turn to other sources of "information," the Internet or a neighbor, for the advice they seek.

Second, it is clear that reinforcing public trust in immunization will take all of our collective efforts. You will need to tell us how this effort can serve your needs. That's why I asked you to think about what you are hearing from your patients.

Indeed, even before we cross the line into the new millennium we must recognize that we have already entered a new era. Communicating the value of immunization is no longer a matter of to simply outlining the risks of disease. The fact that many of the patients and parents we see have never known anyone to suffer from these diseases means they are unlikely to be able put its risk in context. Disease is not their only concern. They have new concerns as well. We need to improve our efforts to respond to those concerns and learn how to effectively communicate what we know about the safety and effectiveness of our vaccines.

Immunization is a success story that is not over. We look forward to working together with you not only to expand our victory over infectious diseases but also to maintain and strengthen the public's confidence in our immunization and public health programs.

Dr. Louis Sullivan is the President of Morehouse School of Medicine, Co-Chair of the National Network for Immunization Information's Steering Committee, and was Secretary of the U.S. Department of Health and Human Services in the Bush Administration, 1989-1993.