Statistical Study Estimates How Many Anthrax Cases Were Prevented

Join Our Community of Science Lovers!

In case there were any doubts, a new study indicates that the widespread administration of antibiotics in response to the anthrax attack this past October was a good idea after all. Thus far, the Centers for Disease Control and Prevention has confirmed 11 cases of inhalation anthrax, five of which resulted in death. But a statistical analysis of the U.S. outbreak, published today in the journal Science, indicates that twice as many people could have contracted the potentially fatal inhalation form of anthrax had they not taken antibiotics.

By January of this year, public health officials had recommended that approximately 10,000 potentially exposed people undergo a 60-day regimen of antimicrobial prophylaxis. Roughly half of these individuals worked at or had visited one of three exposure sites: a postal facility in New Jersey, another in Washington, D.C., and the Boca Raton offices of American Media, Inc. Focusing on these patients, Ron Brookmeyer and Natalie Blades of Johns Hopkins University developed a statistical model to estimate the probable number of anthrax cases prevented by prophylaxis, based on information about dates of exposure, symptom onset and the anthrax incubation period. Their analysis clearly shows that the antibiotics saved lives, but Brookmeyer notes that an absence of antibiotics would probably have resulted in only nine additional cases.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


In addition to confirming the wisdom of these recent decisions, the study could also influence future public health policy. Brookmeyer says that their finding "demonstrates that earlier intervention and treatment can save lives and must be a critical element of any biodefense strategy."

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe