Doctors and emergency room workers may have been thrown off by the little-known gastrointestinal symptoms of anthrax infections that many of the 10 patients with inhaled version of the disease had -- but they should not be fooled in the future, said Dr. Anthony Fauci, head of the National Institute of Allergies and Infectious Diseases (NIAID).
"You have just go to be very, very alert about these things," Fauci, who helped write a commentary about the findings in the Journal of the American Medical Association (JAMA), said in a telephone interview.
"The signs and symptoms of inhalational anthrax are way up on the radar screen of virtually all health care providers now," said Fauci.
Prior to Oct. 4, when a Florida man was hospitalized with the first recognized U.S. case of inhaled anthrax since 1976, the disease was relatively unknown to most American doctors. In medical terminology, inhaled anthrax was not high on the "index of suspicion" in making a diagnosis.
With the intense publicity given the anthrax-by-mail crisis and the publication in journals of specific medical details of the 10 cases, inhaled anthrax has become an infection that doctors will probably consider.
"Right now in Washington, D.C., it would be inconceivable to me that any postal worker could walk into an emergency room and the person who saw them would not think about anthrax," Fauci said.
Two of four workers at a Washington mail-processing center who contracted the inhaled form of anthrax infection died last month. Both had gone to the hospital but were told they had a virus and sent home.
Fauci said he doubted that would happen again.
"The concern is what happens when things cool down a little and maybe weeks or months go by and then something happens," he said. "The physicians have to be alert."
The JAMA report is the latest of a series detailing the 17 known anthrax cases, all but one of which are believed to have resulted from exposure to anthrax-tainted mail. Investigators are confounded by the death of Kathy Nguyen, 61, in New York, who had no known connection to any of the anthrax letters.
Fauci said the doctors who treated the first few cases may have been fooled by the abdominal pains reported by the patients. Anthrax symptoms have been widely described as starting out looking like influenza, which some people may interpret as meaning respiratory symptoms only. Most of the 10 inhaled anthrax patients had normal or only slightly elevated temperatures early in their illnesses.
But the anthrax bacteria spread quickly through the lymph system and can kill cells in the intestine, causing internal bleeding and abdominal pain.
Irregular heart beats, "disproportionate to the degree of fever," were also reported, Fauci said.
Doctors also found abnormalities on chest X-rays and CT scans. Most common was an increased density in the area between the two lungs.
"Based on these observations, primary care clinicians should be encouraged to obtain chest radiographs and consider chest CT scanning to aid in the diagnostic workup of patients in whom inhalational anthrax is a diagnostic consideration," they said.
"If you read the textbooks, the disease is not exactly what we are finding," he said.
Fauci pointed out that 40 percent of the inhaled anthrax patients died -- a much lower rate than the 90 percent mortality from the disease in past years.
"It might have been even less had there been alerting to this on the part of the first two unfortunate Brentwood workers," he said. "Almost certainly if these people had been treated really early, they would have done even better."
This illustrates one big problem in medicine, Fauci said. An outbreak, whether natural or in a biological attack, cannot be detected until somebody gets sick.
"That is unfortunate ... but the reality is the only way you can see and track and form epidemiological patterns is when people get sick. Then you can look at it and say 'this is the pattern that is happening'," Fauci said.
The next thing doctors should look out for is when people who may have been exposed to anthrax spores stop taking their antibiotics. Last week the Centers for Disease Control and Prevention (CDC) said 32,000 people were taking drugs because they may have breathed in spores.
Fauci said many people may never have developed infections because they took the drugs. "You just do not know what the toll would have been had there not been aggressive use of prophylactic antibiotics," he said.
But animal tests have shown the spores can survive in the body longer than the 60 days that people are taking the drugs.
"After the 60 days are up, those people who have been treated must pay particular attention to the emergence of symptoms," Fauci said. "It is highly likely that they are totally safe but there has to be a high degree of vigilance."
Fauci and other experts said no one should be lulled into a false sense of security.
"There is no reason to believe this will be an isolated act of bioterrorism," they wrote in the JAMA report. "In fact, it is likely that additional attacks involving Bacillus anthracis and perhaps other pathogens will occur."
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