Despite promising advances, clinicians, hospitals, and public health officials remain largely unprepared for a global influenza pandemic similar to the one in 1918 that killed more than 50 million people worldwide, according to an expert panel that held a Feb. 1 teleconference during the Seasonal & Pandemic Influenza 2007 meeting.
Primary care physicians on the front line of diagnosis and initial response need a better appreciation of the current morbidity and mortality caused by seasonal influenza outbreaks in the United States, Dr. Richard Whitley said. An influenza pandemic may incite more fear among physicians and the public, but seasonal influenza causes an estimated 36,000 deaths and more than 200,000 hospitalizations each year, said Dr. Whitley, professor of pediatrics at the University of Alabama, Birmingham.
The American Academy of Pediatrics (AAP) and the American Academy of Family Physicians need to stress the importance of influenza vaccinations for members and the patients they treat, Dr. Whitley said. “This message has been ignored for many years.
“We need to immunize more children,” as they are a main source of infection for other family members, including high-risk groups such as the elderly and the immunocompromised. There have already been 100 children admitted to Children's Hospital in Birmingham and nine deaths so far in the United States during the 2006-2007 influenza season,” Dr. Whitley said. “So we've well exceeded acceptable levels of morbidity and mortality.”
“This applies to physicians who take care of adults as well,” said Dr. John Bartlett, professor of medicine at Johns Hopkins University, Baltimore. “The current vaccination [rate] is good in elderly, less so in the immunocompromised patients, and poor in health care workers, about 40%.” Clinicians have a duty to protect themselves and their patients, he said.
One proposal for boosting vaccination rates among hospital-based health care providers is to make mandatory the reporting of such rates to the Joint Commission on Accreditation of Healthcare Organizations. In addition, the Infectious Diseases Society of America (IDSA) is reportedly going to push for immunization of all health care workers.
“We've made some substantial advances but we have a long way to go,” said Dr. Anthony Fauci, director, National Institute of Allergy and Infectious Diseases (NIAID), Bethesda, Md. One goal is to reduce the prohibitively high doses of influenza vaccine that would be required during a pandemic. One promising finding is that there appears to be a “good degree of cross protection” from the vaccination of animals and/or humans, although clinical trial results are still needed to confirm this effect.
A quick point-of-care test for pandemic strains of influenza is in development, according to panel members. A similar test for seasonal influenza strains is limited by its long turnaround time. “We need to get point-of-care diagnostics down to a time frame that is clinically useful. Now it takes several hours to do,” Dr. Bartlett said. Having more rapid diagnostic assays would allow for more judicious use of antibiotics, particularly in children.
Panel members focused on the prevention of a bird flu pandemic caused by the H5N1 lethal strain of influenza virus subtype that mainly infects birds. As of Jan. 30, 270 confirmed human H5N1 cases and 164 human deaths had been reported. Most affected humans had been in close contact with infected poultry.
“The greatest concern … is the resurgence of these viruses in countries such as Japan and Korea. … It suggests migratory birds have probably brought these viruses back in,” said Robert Webster, Ph.D., professor of virology at St. Jude Children's Hospital in Memphis, Tenn., and director of the World Health Organization's Center on Studies on the Ecology of Influenza in Animals and Birds.
The current resurgence following aggressive eradication efforts raises the question of what is the ultimate reservoir, Dr. Webster said. Until that is identified, “we cannot control it [H5N1]. … These viruses are diversifying at an amazing rate.”
If a pandemic like 1918's pandemic occurred today, it would cause an estimated 62 million deaths worldwide (Lancet 2006;369:2211-8). Health care resources in the United States would be quickly overwhelmed, according to data from the Center for Biosecurity at the University of Pittsburgh. Researchers estimated an influenza pandemic similar to 1918 would take 191% of the beds in the United States.
Response to an influenza pandemic should be tailored to the extent of the outbreak—whether it is widespread as in 1918 or more mild, as in 1968, experts said. The Centers for Disease Control and Prevention is releasing a strategy to rate pandemic outbreaks on a scale of 1 to 5, similar to what is used to rate hurricane intensity.