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A new era of bioterrorism has begun with the intentional anthrax scares that have left several people dead and many more exposed as this issue went to press. But amid the shrill coverage of the widening anthrax investigations, the scramble for gas masks and the expected hoarding of Cipro, there must be a voice of calm and reason. That voice must be your own.
Infection control professionals, hospital epidemiologists, and other key clinicians involved in health care bioterrorism readiness and response must set the tone for a panicky public and an uneasy health care work force, emphasizes veteran epidemiologist William Schaffner, MD, chairman of preventive medicine at Vanderbilt University School of Medicine in Nashville. "We have to re-instill a sense of confidence for people who work in the health care system," he says. "Start with the doctors. They are the ones who are going to be more panicked than the nurses."
The current situation is reminiscent of the early stages of the HIV epidemic, when there was much anxiety about the communicability of the disease and whether even casual contact would spell a death sentence for health care workers. In that chilling time of alarmist reactions and burning mattresses, Schaffner recalls that ICPs, epidemiologists, and other clinicians, stepped into the fray to provide calming confidence and accurate risk data. "I’m beginning to think that we may be in a similar position now," he says. "We could have a very powerful educational and reassuring effect. Everybody’s anxious about this, but I think we can diminish the level of anxiety," Schaffner adds.
Health care workers must be educated about bioterrorism agents and provided reassurance that the patient isolation precautions developed by the Centers for Disease Control and Prevention (CDC) are extremely effective, urges Schaffner.1 "The barrier precautions are going to work for bioterrorism. Once you get to chemical [weapons] then you get into the whole moon suit’ issue. But for bioterrorism, we don’t need that," he says.
For example, systems of barrier precautions such as gloves, gowns, and masks to isolate patients infected with all manner of infectious diseases are already in place in virtually all U.S. hospitals. "They work," he says. "Look, we all know pulmonary tuberculosis is communicable. I’m an infectious disease doctor, have been for 30 years. I’ve seen a lot of patients with tuberculosis, but I have also been meticulous about my use of [face masks and respirators]. My tuberculin test continues to be negative."
And anthrax, of course, is not communicable from person to person, reminds Schaffner, who investigated a case of occupational anthrax in an animal-hide worker when he was a epidemiologist for the CDC in the late 1960s. "The bacteria do not cause a conventional pneumonia," he says. "They replicate locally and then release toxins. Because the bacteria never replicate to very high numbers the person is not communicable. It is not so much an infection as it is an intoxication."
Inordinate fear of anthrax could cause another problem — hoarding and misuse of Ciprofloxacin and other antibiotics. That tactic eventually could contribute to emerging resistance in pathogens such as Streptococcus pneumoniae, Schaffner notes. "It is one thing for a hospital and the health department to develop an inventory in the event of an emergency," he says. "I do not recommend that individuals do that. I’m quite concerned that with antibiotics in their medicine cabinets there will be a temptation to just use it now and again for inadequate reasons in inadequate doses. If there was a recipe for antibiotic resistance — that’s it."
While the anthrax mailing campaign now under way sends out another shock wave with every news report, the tactic will likely result in more terror than actual toll. The rapid administration of antibiotics has offset illness following exposures, the disease is not communicable from those actually infected, and everyone is now on high alert for suspicious mailings. Indeed, if the wave of anthrax mailings continues, postal-treatment technologies may become a growth industry.
Regardless, anthrax is problematic as a bio-weapon because only a certain micron size of the inhaled spore will lodge in the upper lungs where it can release its toxins, says Allan J. Morrison Jr., MD, MSc, FACP, a bioterrorism expert and health care epidemiologist for the Inova Health System in Washington, DC. "If it is too large, it won’t go in," says Morrison, a former member of the U.S. Army Special Forces. "If it’s too small, it goes in and moves about freely without ever lodging. This is not as easy as getting a culture, growing it in your home, and the next day having infectious microbes.
"The sizing, preparation, and ability to deliver such a weapon are extremely difficult," he adds.
The Aum Shinrykyo cult in Tokyo attempted at least eight releases of anthrax or botulism during 1990 to 1995 without getting any casualties, he recalls. (See "A bioterrorism time line," in this issue.) Variables such as humidity can come into play, clumping up spores even if they are perfectly sized for inhalation. Anthrax spores bound for human targets are also at the whims of ultraviolet light, rain, and wind dispersal patterns, Morrison says.
"It is a very hostile climate for microbes on planet earth." Morrison says. "The intent may be widespread, but the ability to deliver weapons grade agents is going to be restricted to a very small subgroup. And even among them, they still will require optimal climatic conditions to carry it out. There will be causalities, as in war, but the distinction here is that there has not been widespread infection."
While anthrax is the current weapon of choice, the direst scenarios usually turn to the most feared weapon in the potential arsenal of bioterrorism: smallpox. "Invariably, I have seen smallpox described as highly infectious,’" Schaffner says. "It’s not. That is erroneous." For example, during the global eradication efforts in the 1960s, African natives infected with smallpox were often found living with extended families in huts, he adds. "It would usually take two to three incubation periods for smallpox to move through an extended family."
"It doesn’t happen all it once. This was a critical concept in the strategy to eradicate smallpox. If you could find smallpox, you could vaccinate around that case and prevent further transmission. If it had been a frighteningly [rapid] communicable disease, that strategy would never have worked," Schaffner explains.
In addition, some medical observers question the certitude of the general consensus that all those vaccinated decades ago are again susceptible to smallpox. They argue that those immunized during the eradication campaign may at least have some greater protection against fatal infection.2 Regardless, rather than dropping like flies, as many as 70% of those infected with smallpox actually survive and then have lifelong immunity.
While there are many other agents to discuss and prevention plans to outline in the weeks and months ahead, perhaps the greatest protective factor is the unprecedented level of awareness in the health care system. The world has changed so much since Sept. 11th that hospitals are probably more prepared for bioterrorism than they have ever been. Everywhere, lines of communication have been opened with health departments and affiliated clinics, emergency plans have been reviewed and hot-button phone numbers posted on the wall.
"We’re on alert," says Fran Slater, RN, MBA, CIC, CPHQ administrative director of performance improvement at Methodist Hospital in Houston. "We are all on alert."
1. Garner JS, the Centers for Disease Control and Prevention Hospital Infection Control Practices Advisory Committee. Guideline for Isolation Precautions in Hospitals. Web site: www.cdc.gov/ncidod/hip/ISOLAT/isolat.htm.
2. Bosker G. Bioterrorism: An update for clinicians, pharmacists, and emergency management planners. Emergency Medicine Reports (in press) 2001.