In the July 2014 issue, the piece “Resurrecting the 'yuppie vaccine'” (Nat. Med. 20, 698, 2014) stated that “LYMErix originated in the late 1980s in a laboratory at the Yale School of Medicine at Yale University” and that “[b]y 1992, SmithKline Beecham had licensed the vaccine.” However, it failed to mention the work of a team of German researchers, including Markus Simon and Ulrich Schaible at the Max Planck Institute and Michael Kramer and Reinhard Wallich of the University of Heidelberg, who published initial key findings laying the groundwork for the LYMErix vaccine against Lyme disease. The error has been corrected in the HTML and PDF versions of this article.

In the September 2014 issue, the piece “Blood feud: The debate over how long blood lasts” (Nat. Med. 20, 979–982, 2014) stated that proteins in stored blood “can scavenge nitrous oxide” and that “nitrous oxide might tighten blood vessels.” However, the story should have referred to nitric oxide, not nitrous oxide. The error has been corrected in the HTML and PDF versions of this article.