This special issue, dedicated to the Second ISIRV International Symposium on Neglected Influenza Viruses, has 12 manuscripts that cover many aspects of the biology of non-human/non-avian Influenza.

Through these manuscripts, information is shared on issues related to epidemiology, diagnostic test evaluation, evolution, and pathology, mainly concerning swine and equine influenza. These studies were conducted by researchers from different regions of the world (Europe, North America, and South America), showing a widening participation of influenza researchers in an effort to understand the emergence of new viral variants, provide new tools for the control of this pathogen and thus improve the health status of important animal species that are seldom-studied natural hosts for influenza viruses. The knowledge gained concerning these species will certainly contribute to a better understanding of the emergence of human and animal pandemics and to better preparation for the threat of zoonotic influenza.

The Second ISIRV International Symposium on Neglected Influenza Viruses was held at the Royal College of Physicians in Dublin, Ireland, on March 7–8, 2013. This meeting focused upon influenza viruses of swine, dogs, horses, and seals, under the headings of surveillance and disease investigation, virus transmission and control, clinical and experimental virology, and emerging issues/new developments. There were 83 participants from 22 countries, with 13 invited speakers, 25 oral presentations chosen from submitted abstracts, and 38 poster presentations. We are grateful to Professors Ann Cullinane of the Irish Equine Centre, Gregory Gray of the University of Florida, and Debra Elton of the Animal Health Trust UK, for organizing this successful meeting under challenging circumstances and look forward to the third meeting in 2015.

We would like to thank all the authors for their outstanding work and also thank ISIRV, the publishers of the Influenza and Other Respiratory Viruses Journal, for their contributions to assure an efficient process to evaluate and publish this special issue.