In their letter, Barbieri et al. (1) cite valuable works on human ectoparasite transmission well known to us. Indeed, we previously tested alternatives to the rat/rat–flea mechanism of transmission and found that a model with human ectoparasites was the most appropriate in Europe (2, 3) where there were no known wild-rodent reservoirs (4). Thus, we agree with Barbieri et al. (1). However, for our most recent paper (5), we did not have the genetic information to address the question of transmission modalities. At our current level of knowledge, we can only interpret the genetic data in a phylogenetic context and explore the routes taken by plague to reach Europe in light of the historical information.
Contrary to what Barbieri …
↵1To whom correspondence may be addressed. Email: n.c.stenseth{at}ibv.uio.no, barbara.bramanti{at}ibv.uio.no, or amine.namouchi{at}ibv.uio.no.
