Randolph and Dobson published a Special Issue Article (Randolph, S. E. and Dobson, A. D. M. (2012). Pangloss revisited: a critique of the dilution effect and the biodiversity-buffers-disease paradigm. Parasitology 139, 847–863), which prompted Dr R. Ostfeld to ask if the journal published letters commenting on published articles, and his case the Randolph and Dobson's paper. We do not have this facility but we told Dr Ostfeld that he could make his comments through a paper submitted to the journal, which would go through the normal peer review process. If his paper was accepted for publication we would give Randolph and Dobson an opportunity to respond to his criticisms through a short Commentary article. Dr Ostfeld's article is published below and is followed by Randolph and Dobson's response.