# Mathematical Digest

### Short Summaries of Articles about Mathematics

in the Popular Press

"New Look at Old Data Irks Smallpox-Eradication Experts," by Martin Enserink. *Science,* 10 January 2002, page 181.

Ring vaccination is a post-outbreak strategy in which smallpox victims are isolated and those who've come in contact with them are quickly immunized. Evidence from ring vaccination done in parts of Africa in the late 1960s seems to support the effectiveness of the strategy but Edward Kaplan, a mathematician from Yale, disagrees. He and Lawrence Wein have published a paper in the January 2003 issue of *Epidemiology* challenging the strategy in general and especially disputing a graph which is often cited to prove that ring vaccination worked. Kaplan says that some of what he claims is a misinterpretation of the graph comes from its logarithmic scale for the number of smallpox cases (plotted against time). Some of the irked experts who are unconvinced by Kaplan's arguments are co-authors of papers in the 1970s that included the graph. One of the co-authors, Donald A. Henderson, is now an advisor to the Bush administration. Although Henderson concedes that the graph isn't perfect, he says that there is other evidence overwhelmingly in favor of ring vaccination.

*--- Mike Breen *