Molecular Epidemiology of Hantavirus Infections

Abstract

Hantaviruses cause two human zoonoses, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS), and are prime examples of “emerging viruses ”. Hantaviruses form a separate genus within the family Bunyaviridae. In contrast to most members of the family, hantaviruses are not arthropode-borne viruses (arboviruses); they are maintained in persistently infected rodent hosts and transmitted by aerosolized contaminated excrements, i.e., not transmitted by any insect vectors. Therefore, they should more adequately be regarded as rodent-borne viruses, or roboviruses. Hantaviruses seem to co-evolve with their natural rodent reservoirs, as each hantavirus species is predominantly associated with one specific rodent species. This has resulted in the establishment of unique sets of hantaviruses that circulate in Asia, Europe, and North and South Americas, respectively and are harbored by indigeneous rodent species. There are several potential explanations for the emergence of hantaviruses, e.g., changes in rodent population density or the movement of humans into close contacts with rodents (e.g., during military conflicts). The recent rapid progress in the characterization of the causative agents and diagnosis of human infections are also decisive for the increasing number of recognized hantavirus infections.