This research has been published in the article "Recombination drives genome evolution in outbreak-related Legionella pneumophlia isolates" in the journal Nature Genetics, and the study describes in detail the whole genome sequencing of 69 isolates from 13 of the 18 historical legionella outbreaks occurred in Alcoy. Researchers have discovered that more than one strain is found in some of the outbreaks studied and that the genetic differences between these strains are such that suggest that there are different sources for one outbreak.