Key Symptoms Differentiating Inhaled Anthrax From Influenza Identified by NewYork Weill Cornell Study

NEW YORK -- -- Physician-scientists in the Department of Public Health at NewYork Weill Cornell Medical Center have identified key symptoms that may help distinguish inhaled anthrax from the flu and other common respiratory conditions in the event of a bioterrorist attack, according to a new study published in the Sept. 2, 2003 issue of Annals of Internal Medicine. Study results have allowed the NewYork-Presbyterian Hospital and Weill Cornell Medical College physician-researchers to create the first evidence-based pre-hospital screening protocol that is designed to differentiate anthrax from the flu in case of a bioterrorist attack.

The study found that while both anthrax and common respiratory conditions presented with symptoms such as fever and cough, other symptoms -- such as the neurologic symptoms of loss of consciousness, dizziness, and confusion; serious gastrointestinal symptoms like nausea and vomiting; and shortness of breath -- were much more common in patients with inhaled anthrax. Conversely, sore throat and runny nose more often indicated viral infection rather than bacterial anthrax.

"In the case of bioterrorist attack, it is vitally important that physicians' offices and hospital emergency departments accurately diagnose anthrax, especially considering that laboratory or radiographic testing would not be feasible if there were a high volume of potential cases," said lead study author Dr. Nathaniel Hupert, assistant professor of public health and medicine at Weill Cornell Medical College and assistant attending physician at NewYork-Presbyterian Hospital Weill Cornell Medical Center. "Four of the 11 patients who developed anthrax in 2001 were originally sent home with diagnoses of a viral syndrome, bronchitis, or gastroenteritis."

The new anthrax protocol will help emergency management and public health authorities more rapidly and accurately identify both potential cases and likely non-cases. Physicians assisted by the use of the protocol in the setting of an anthrax attack may help to preserve scarce hospital capacity while ensuring that patients receive appropriate advanced medical care, added Hupert.

Combining data from the 11 inhaled anthrax cases from the 2001 attacks with historical case reports of 17 additional patients, Hupert and his colleagues compared the features of anthrax-related illness with more than 4,000 cases of common viral respiratory tract infections such as the flu. The protocol was then developed by determining the relative frequency of various clusters of symptoms and physical exam findings in inhalational anthrax compared to other common respiratory illnesses that could mimic or obscure the diagnosis of anthrax infection.

Co-authors of the study were Dr. Alvin Mushlin, chairman of the Department of Public Health at Weill Cornell Medical College and attending physician at NewYork-Presbyterian Hospital Weill Cornell Medical Center; Dr. Mark Callahan, associate professor of public health and medicine at Weill Cornell Medical College and associate attending physician at NewYork-Presbyterian Weill Cornell; and Dr. Gonzalo Bearman, now of the Medical College of Virginia, Virginia Commonwealth University.

"This study provides the critical foundation needed to direct further science-based research in this important area," said Dr. Carolyn Clancy, director of the Agency for Healthcare Research and Quality (AHRQ) of the U.S. Department of Health and Human Services (HHS), which funded the study as part of its bioterrorism preparedness research portfolio.

Anthrax is an infectious disease caused by spore-forming bacteria. Inhalation of anthrax spores leads to disease caused by the release of two bacterial toxins: edema factor and lethal factor. Without proper treatment, death occurs rapidly from a combination of shock and respiratory compromise.

Since 2000, Weill Cornell Medical College Department of Public Health has pioneered approaches to bioterrorism preparedness -- including the development of computer models for determining optimal antibiotic and vaccine dispensing; research on hospital capacity to treat mass casualties for a bioterrorist event; and extensive educational activities for medical students, residents, and practicing physicians. With $1 million in research funding for these efforts, faculty from Weill Cornell have been working with the Centers for Disease Control and Prevention (CDC), and the Agency for Healthcare Research and Quality (AHRQ) of the Department of Health and Human Services to research solutions for and educate emergency management and public health officers around the country about the design and operation of antibiotic and vaccine prophylaxis centers.

In June, the U.S. Department of Health and Human Services announced the release of a new computer model, developed by Dr. Nathaniel Hupert and the Department of Public Health, that will help health officials better plan large-scale antibiotic dispensing and vaccination responses to bioterrorism and large-scale epidemics. Funded by AHRQ, this is the first such computer model that hospitals and public health agencies can easily download and customize to meet their local needs. The computer model will be made available to all 50 states and major U.S. cities in order to help them comply with Federal guidelines on preparedness for large-scale disasters.

Source: NewYork Weill Cornell Medical Center