Infectious disease experts have called for renewed vigilance against influenza and pneumococcal disease. This call to action was issued at a press conference convened by the National Foundation for Infectious Diseases (NFID) and the National Coalition for Adult Immunization (NCAI). The conference, held in Washington, DC on October 13,1998, coincided with National Adult Immunization Awareness Week and was held in conjunction with an international pneumococcal vaccine conference, "Pneumococcal Vaccines for the World," co-sponsored by the World Health Organization (WHO).

Influenza is responsible for more than 100,000 hospitalizations and 20,000 deaths annually in the United States. "The excess deaths that we see with influenza are only the tip of the iceberg," said W. Paul Glezen, MD, head of the preventive medicine section of the departments of microbiology and immunology and pediatrics at Baylor College of Medicine. "For each death, there are 10 to 15 hospitalizations for acute respiratory illness and millions of healthcare visits...We expect this situation to become even worse with the aging of the population, the increase in population density, and the rapid dissemination of new flu viruses by movement of people around the world."

"Influenza remains a serious threat, especially to older Americans. There is an effective influenza shot, but it is not getting to as many people as it should," said William J. Martone, MD, senior executive director of NFID. "We're calling on the medical community and the public at large to consider getting an influenza shot."

According to the CDC, it is estimated that during most influenza seasons, approximately 10 to 20 percent of the population is infected with influenza, although rates of infection vary among different age groups and from one season to another. Up to one percent of those infected will require hospitalization and among those, as many as eight percent die.

The consequences of influenza -- which include pneumonia and death -- are especially pronounced in high-risk groups: people age 65 and older and those with other medical conditions, such as asthma, diabetes or chronic heart failure. Yet, the influenza vaccine remains underused among this population. In the 1997 Behavioral Risk Factor Surveillance System, 65 percent of persons 65 years and older said they received influenza vaccine in 1997. Among elderly minorities, only 50 percent of blacks and 58 percent of Hispanics reported receiving influenza immunization in 1997.

Each year, a new influenza vaccine is developed to protect humans against the disease. Because influenza viruses are able to mutate rapidly and produce new surface antigens, the vaccine produced against last season's viruses may not offer complete protection against viruses this year. In addition, vaccine-induced immunity wanes after several months.

Scientists must know by mid-February, at the very latest, which virus strains to include in the following season's formulation to ensure production of adequate amounts of vaccine for delivery in time for influenza vaccinations in October and November.

"It is projected that for the 1998-99 season, over 80 million doses of flu vaccine will be produced approximately the same amount that was produced last year," said Keiji Fukuda, MD, epidemiology section chief of the CDC's Influenza Branch. "One vaccine manufacturer has reported that its production will be lower than expected and its shipments will be delayed. However, deliveries by the other three companies are expected to be on schedule and in amounts that will satisfy overall demand."

Paul-Henri Lambert, MD, chief of vaccine research and development, WHO, stated that of the 15-17 million persons who die worldwide each year from infectious diseases, 15 to20 percent succumb to pneumococcal disease.

Less than half of all American adults 65 and older, and barely a third of older minority adults, are protected against a pneumococcal disease, an infection that claims as many as 40,000 lives each year in the United States and millions more worldwide. While the number of adults vaccinated against pneumococcal disease is showing an upward trend, according to a state-by-state survey recently released by the Centers for Disease Control and Prevention (CDC), leading infectious disease and immunization specialists encourage more attention to older Americans' vaccination needs.

Jay C. Butler, MD, an infectious disease specialist with the CDC and a leading authority on antibiotic resistance, emphasized the danger to public health posed by pneumococcal infection.

"Pneumonia and influenza together are the fifth leading cause of death among the elderly in the United States. Each year, 75,000 persons age 65 and older died of pneumonia and influenza," said Dr. Butler. "The pneumococcus is the most common cause of bacterial pneumonia. Nearly one-third of adults hospitalized with pneumococcal pneumonia also develop blood stream infection."

Each year in the United States the pneumococcus, or Streptococcus pneumoniae, is responsible for more than 50,000 cases of bacteremia, 3,000 cases of meningitis, 500,000 cases of pneumonia, and an estimated seven million ear infections. Currently available pneumococcal vaccines, called polysaccharide vaccines, are effective against invasive pneumococcal infections bloodstream infections and meningitis.

James Singleton, epidemiologist for CDC's National Immunization Program, summarized the state-by-state findings of the latest adult immunization study, published in the Morbidity and Mortality Weekly Report (MMWR) of October 2, 1998. Singleton highlighted the findings on pneumococcal vaccination in our nation's minority populations. "Unfortunately, two-thirds of minority adults age 65 and older have not been vaccinated against this deadly disease," he said.

Pneumococcal vaccination levels for Hispanic persons 65 years of age and older were 34.1 percent and for non-Hispanic blacks it was 29.7 percent. In contrast, the rate was 47.3 percent for non-Hispanic whites. Mr. Singleton urged physicians to recommend pneumococcal vaccination to their patients when indicated, and urged states to include pneumococcal vaccination in their adult immunization campaigns. "From every perspective public health, cost and quality of life it doesn't make sense not to immunize those at risk," he said.

Pneumococcal vaccination, which can be given at the same time as an influenza vaccination, is reimbursable under Medicare Part B. The pneumococcal vaccine is generally given only once, although certain groups may require reimmunization after five years.

David Fedson, MD, director of medical affairs at Pasteur Merieux MSD in Lyon, France, spoke about his recently published findings on the role of policy on pneumococcal vaccination.

Dr. Fedson called for making adult immunization an integral part of national public health systems, similar to mandates for childhood immunization. "We have vastly underestimated the impact of pneumococcal disease on public health throughout the world," he said. "Pneumococcal vaccination is potentially one of the most powerful, cost-effective weapons in the global war against disease and human suffering." The NFID/NCAI press conference was supported, in part, by unrestricted educational grants to NFID and NCAI by Merck Vaccine Division, Pasteur Merieux Connaught, and Wyeth-Lederle Vaccines and Pediatrics.