R
ecognition of viruses as a major contributor to vector-borne diseases and other zoonoses dates back many decades. The term arbovirus (arthropod-borne virus) is widely recognized even among the lay public. A few rodent-borne viruses recognized long ago (e.g., the arenaviruses associated with Lassa fever and South American hemorrhagic fevers, and the hantaviruses associated with hemorrhagic fever with renal syndrome in Asia and Europe) were discussed under the rubric of arboviruses and even listed in the Arbovirus Catalog. A turning point came 17 years ago with the discovery of the often-fatal hantavirus pulmonary syndrome in the Americas. This discovery stimulated interest, funding, and research on rodent hosts of viruses and led to the discovery of dozens of new hantaviruses and arenaviruses; ultimately, the study of roboviruses (rodent-borne viruses) became a discipline in itself. In the last few years, we have learned that a separate order of mammals, the insectivores, are also hosts to likely dozens of hantaviruses whose role in disease is uncertain. The roboviruses have become the rainboviruses (rodent- and insectivore-borne viruses). The discovery of this tremendous diversity of viruses and hosts and the desire to understand their relationships to human disease and to environmental change have spawned new theories, controversies, and terminology: coevolution, cospeciation, spillover, host-jumping, bottom-up trophic cascades, dilution effects, and delayed density-dependence. The development of these concepts and much of the rapid growth in understanding of host–virus–human disease relationships are due to a multidisciplinary approach that combines ecology, epidemiology, virology, and molecular biology.
This issue of Vector-Borne and Zoonotic Diseases includes a sampling of articles that capture some of the excitement of this new and rapidly growing field of study. The following 10 articles concern viruses belonging to the family Arenaviridae, genus Arenavirus and family Bunyaviridae, genus Hantavirus. Included are two up-to-date reviews of hantavirus–host ecology in Europe and North America and eight cutting-edge research papers on rodent-borne and insectivore-borne hantaviruses and rodent-borne arenaviruses. Collectively, these articles are indicative of the growing interest of the journal's readership in zoonoses caused by pathogens that are naturally associated with rodents or other small mammals.
