Zeroing in on respiratory infections (American College of Physicians annual session)

Those closely monitoring the global spread of avian influenza in the context of a pandemic threat don't know if, when or how such an outbreak will occur, but they are sure of two things: A bird infected with this virus will turn up in the United States, and the earliest human cases most likely will be detected by an office-based primary care physician.

"All primary care physicians are the front lines of public health," said Anna M. Likos, MD, MPH, medical epidemiologist in the Centers for Disease Control and Prevention Influenza Branch. "If they don't call us, we won't know, and that's going to be essential in terms of containment."

That's why the American College of Physicians annual session last month in Philadelphia featured several seminars on this and other infectious disease threats.

"The fear of an emerging pandemic is one of the things that's made us all try and be more prepared," said Donna E. Sweet, MD, immediate past chair of ACP's Board of Regents.

With regard to avian influenza, public health officials are calling on physicians to report any patient who has severe respiratory illness with no known cause and has traveled to a country where such infections have been occurring. In addition, public health agencies are expected to endorse an official recommendation that such patients should have had significant contact with poultry for their illness to be considered a possible case. "Avian influenza appears at this time to require direct close contact," Dr. Likos said.

Data collected on human cases seem to indicate that lower respiratory tract symptoms early in the infection and diarrhea in an adult with influenza could be warning signals. "Kids usually get diarrhea with influenza, but diarrhea in adults is much more common with H5N1 infection than we're used to seeing," Dr. Likos said.

Examining existing system problems

Experts also cautioned that when this or another influenza strain emerges as a pandemic, physicians will be expected to play a significant role in providing care and vaccinations. Those in attendance complained, though, that recent seasonal flu vaccine supply experiences, which have been marked by difficulties, create a lack of confidence that distribution during a pandemic would occur in any sort of effective fashion.

"At least three out of the last four years, our vaccine has come in late. Half the orders were never filled," said Patrick T. G. Hennessey, MD, MPH, medical director of the EastCoast Medical Network, in Orlando, Fla. "Our national influenza vaccine distribution policy is a non-policy and a disgrace."

Stabilizing this supply chain has been the focus of efforts by medical societies and public health agencies. The American Medical Association and the CDC, for instance, organize a National Influenza Vaccine Summit annually to focus on the process. Many of these experts believe that pandemic preparedness is adding momentum to the push for a solution to the chronically unstable seasonal flu vaccine system. "We see pandemic flu preparedness as being one way where we can try to fix the supply issue," said Anand K. Parekh, MD, MPH, a medical officer at the Dept. of Health and Human Services.

ACP also issued its policy paper, "Health Care Response to Pandemic Influenza." The group supports the national pandemic plan but feels that it does not do enough to include primary care physicians who work in the outpatient care settings where about 50% of those who become sick in such a crisis will seek treatment.

"The government's current plan needs to go further to involve all physicians," said ACP Deputy Executive Vice President John A. Mitas II, MD. "ACP encourages the government to focus not only on hospitals, as they have, but on internists and primary care physicians as the source of care."

ACP officials warn that inclusion of office-based physicians at all levels of pandemic planning is key to ensure the detection of the initial cases and prevent hospitals from becoming overwhelmed. An emphasis on the outpatient setting also might reduce the chance that those who remain healthy will be exposed.

The policy statement calls for increased access to two-way communication between physicians and public health officials, protecting patient confidentiality as much as possible, equitable distribution of vaccine and antivirals, and ensuring the safety of physicians who are storing and administering vaccines. Those not directly involved in the actual planning also should get copies of the plans that result.

But while avian influenza is in the news, infectious disease specialists say there are many respiratory illnesses that are less common than seasonal flu or colds but still could turn up. Many expect severe acute respiratory syndrome to re-emerge, although a case has not been reported since April 2004. Also, pertussis has become more common among adults and adolescents. But a newly approved vaccine for this age group is expected to make this less of an issue. The Nipah virus, which was first identified in 1999 and has caused significant illness in Bangladesh, Malaysia and Singapore, is also considered a good candidate for causing widespread morbidity and mortality.

"The number of deaths from the Nipah virus probably exceeded that of SARS. The mortality rate is really shocking, and what is scary to me is that there was some fairly good evidence of human-to-human transmission," said Thomas Fekete, MD, associate professor of microbiology and immunology at Temple University School of Medicine in Philadelphia.