(SALT LAKE CITY)If terrorists targeted the United States with an anthrax attack, health care providers and policy makers would need key information such as knowing the likelihood of an individual becoming infected, how many cases to expect and in what pattern, and how long to give antibiotics to protect people from the deadly bacteria.
Those questions gained urgency when anthrax-laced letters killed five people and infected 17 others in the wake of the terror attacks of September 2001. Now, using information from prior animal studies and data from a deadly anthrax exposure accident in Russia in the late 1970s, University of Utah and George E. Wahlen Department of Veterans Affairs Medical Center researchers have developed a mathematical model to help answer critical questions and guide the response to a large-scale anthrax exposure.
In an Aug. 15, 2013, study in PLOS Pathogens online, the researchers use their model to estimate that for an individual to have a 50 percent chance of becoming infected with anthrax (known as ID50), he or she would have to inhale 11,000 spores of the bacteria. A 10 percent chance of being infected would require inhaling 1,700 spores and a 1 percent chance of infection would occur by inhaling 160 spores. The researchers also found that at ID50, the median time for anthrax symptoms to appear is 9.9 days and that the optimal time to take antibiotics is 60 days.
"Anthrax is a well-studied disease and experimental animal data exist, but there is no real good information on dose response for the disease in humans," says Adi V. Gundlapalli, M.D., Ph.D., an infectious diseases specialist and epidemiologist, associate professor of internal medicine at the U of U School of Medicine and staff physician at the Salt Lake City George E. Wahlen Department of Veterans Affairs Medical Center. "We don't want to be overly fearful, but we need to be prepared in the event of a bioterrorism attack with anthrax."
|Contact: Phil Sahm|
University of Utah Health Sciences