in the 1860s and 1870s, when Louis Pasteur, Joseph Lister, and others further developed the germ theory of disease. During 1848, Semmelweis widened the scope of his washing protocol, to include all instruments coming in contact with patients in labour, and used mortality rates time series to document his success in virtually eliminating puerperal fever from the hospital ward. Hesitant publication of results and first signs of trouble Toward the end of 1847, accounts of the work of Semmelweis (as well as the similar conclusions of Oliver Wendell Holmes Sr., working in America) began to spread around Europe. Semmelweis and his students wrote letters to the directors of several prominent maternity clinics describing their recent observations. Ferdinand von Hebra, the editor of a leading Austrian medical journal, announced Semmelweis's discovery in the December 1847 and April 1848 issues of the medical journal. Hebra claimed that Semmelweis's work had a practical significance comparable to that of Edward Jenner's introduction of cowpox inoculations to prevent smallpox. In late 1848, one of Semmelweis's former students wrote a lecture explaining Semmelweis's work. The lecture was presented before the Royal Medical and Surgical Society in London and a review published in The Lancet, a prominent medical journal. A few months later, another of Semmelweis's former students published a similar essay in a French periodical. As accounts of the dramatic reduction in mortality rates in Vienna were being circulated throughout Europe, Semmelweis had reason to expect that the chlorine washings would be widely adopted, saving tens of thousands of lives. Early responses to his work also gave clear signs of coming trouble, however. Some physicians had clearly misinterpreted his claims. Additionally, initial responses to Semmelweis's findings tended to downplay their significance by arguing that he had said nothing new. James Young Simpson, for instance, saw no difference between Semmelweis's groundbreaking findings and the idea presented in an 1843 paper by Oliver Wendell Holmes Sr. that childbed fever was contagious (i.e. that infected persons could pass the infection to others). In fact, Semmelweis was warning against all decaying organic matter, not just against a specific contagion that originated from victims of childbed fever themselves. This misunderstanding, and others like it, occurred partly because Semmelweis's work was known only through secondhand reports written by his colleagues and students. At this crucial stage, Semmelweis himself had published nothing. These and similar misinterpretations continued to cloud discussions of his work