Tula virus

Abstract: Introduction. The isolation by Ho Wang Lee and collaborators of the virus causing Korean haemorrhagic fever, now called Hantaan virus (HTN), from the lungs of striped field mice (Apodemus agrarius) in 1976 (Lee & Lee, 1976) launched a new era in the study of haemorrhagic fever with renal syndrome (HFRS) throughout the world. This was soon followed by the discovery of the causative agent of the European form of HFRS, nephropathia epidemica, now known as Puumala virus (PUU) (Brummer-Korvenkontio et al., 1980), and of the urban rat virus, Seoul virus (SEO) (Lee et al., 1980). The identification in 1993 of Sin Nombre virus (SN) as the causative agent of hantavirus-associated pulmonary syndrome (HPS) (Nichol et al., 1993a) led to intensive search for further hantaviruses and as a result today a total of as many as 16 well-established sero/genotypes may be listed.

Abstract: Unlike other members of the Bunyaviridae family, which must be regarded as arboviruses1, hantaviruses are not transmitted by arthropod vectors, and are exclusively maintained in the populations of their specific rodent hosts. Thus, the prefix “Robo” (from ROdent-BOrne) seems to be more appropriate for the viruses constituting the genus Hantavirus 2. Each of the over 20 currently recognized hantavirus species is predominantly associated with one (or a few closely related) specific rodent species in which it establishes persistent infection. The fact that rodents, or more specifically, rodents alone, constitute the entire host range within which hantaviruses evolve, has several important consequences: (a) Distinctive characteristics of different hantaviruses are formed as adaptations to the distinct genetic environment of their rodent hosts; (b) Contemporary distribution of distinct hantaviruses reflects complicated history of co-speciation events and rodents’ migrations (the most recent extensive rodent migrations were caused by the sequence of several glaciation and deglaciation events in the northern hemisphere). This forms a basis for the circulation of distinct hantaviruses on different continents, their co-existence in some geographic regions, and geographical clustering of hantavirus genetic variants; (c) As a general rule, humans are merely evolutionary “dead-end” hosts for hantaviruses, and thus, human epidemics do not contribute to virus evolutionary process3. As humans are usually naive towards hantaviruses as antigens, that results in sometime dramatic immunological “excesses” leading to high mortality of known hantavirus-caused diseases, severe hemorrhagic fever with renal syndrome (HFRS) (up to 10–12%) and hantavirus pulmonary syndrome (HPS) (up to 40–50%).

Abstract: Hantaviruses (genus Hantavirus, family Bunyaviridae) are enveloped tri-segmented negative-stranded RNA viruses each carried by a specific rodent or insectivore host species. Several different hantaviruses known to infect humans circulate in Europe. The most common is Puumala (PUUV) carried by the bank vole; another two important, genetically closely related ones are Dobrava-Belgrade (DOBV) and Saaremaa viruses (SAAV) carried by Apodemus mice (species names follow the International Committee on Taxonomy of Viruses nomenclature). Of the two hantaviral diseases, hemorrhagic fever with renal syndrome (HFRS) and hantaviral cardiopulmonary syndrome, the European viruses cause only HFRS: DOBV with often severe symptoms and a high case fatality rate, and PUUV and SAAV more often mild disease. More than 10,000 HFRS cases are diagnosed annually in Europe and in increasing numbers. Whether this is because of increasing recognition by the medical community or due to environmental factors such as climate change, or both, is not known. Nevertheless, in large areas of Europe, the population has a considerable seroprevalence but only relatively few HFRS cases are reported. Moreover, no epidemiological data are available from many countries. We know now that cardiac, pulmonary, ocular and hormonal disorders are, besides renal changes, common during the acute stage of PUUV and DOBV infection. About 5% of hospitalized PUUV and 16%-48% of DOBV patients require dialysis and some prolonged intensive-care treatment. Although PUUV-HFRS has a low case fatality rate, complications and long-term hormonal, renal, and cardiovascular consequences commonly occur. No vaccine or specific therapy is in general use in Europe. We conclude that hantaviruses have a significant impact on public health in Europe.

Abstract: Hantaviruses are rodent-borne, emerging viruses that cause life-threatening human diseases in Eurasia and the Americas. We detected hantavirus genome sequences in an African wood mouse (Hylomyscus simus) captured in Sangassou, Guinea. Sequence and phylogenetic analyses of the genetic material demonstrate a novel hantavirus species, which we propose to name "Sangassou virus."