Date Published: February 7, 2013
Publisher: Public Library of Science
Author(s): Wen-Ping Guo, Xian-Dan Lin, Wen Wang, Jun-Hua Tian, Mei-Li Cong, Hai-Lin Zhang, Miao-Ruo Wang, Run-Hong Zhou, Jian-Bo Wang, Ming-Hui Li, Jianguo Xu, Edward C. Holmes, Yong-Zhen Zhang, Connie S. Schmaljohn.
Hantaviruses are among the most important zoonotic pathogens of humans and the subject of heightened global attention. Despite the importance of hantaviruses for public health, there is no consensus on their evolutionary history and especially the frequency of virus-host co-divergence versus cross-species virus transmission. Documenting the extent of hantavirus biodiversity, and particularly their range of mammalian hosts, is critical to resolving this issue. Here, we describe four novel hantaviruses (Huangpi virus, Lianghe virus, Longquan virus, and Yakeshi virus) sampled from bats and shrews in China, and which are distinct from other known hantaviruses. Huangpi virus was found in Pipistrellus abramus, Lianghe virus in Anourosorex squamipes, Longquan virus in Rhinolophus affinis, Rhinolophus sinicus, and Rhinolophus monoceros, and Yakeshi virus in Sorex isodon, respectively. A phylogenetic analysis of the available diversity of hantaviruses reveals the existence of four phylogroups that infect a range of mammalian hosts, as well as the occurrence of ancient reassortment events between the phylogroups. Notably, the phylogenetic histories of the viruses are not always congruent with those of their hosts, suggesting that cross-species transmission has played a major role during hantavirus evolution and at all taxonomic levels, although we also noted some evidence for virus-host co-divergence. Our phylogenetic analysis also suggests that hantaviruses might have first appeared in Chiroptera (bats) or Soricomorpha (moles and shrews), before emerging in rodent species. Overall, these data indicate that bats are likely to be important natural reservoir hosts of hantaviruses.
Emerging infectious diseases have a substantial and ongoing impact on public health and agricultural production –. Over half of the currently recognized pathogens are zoonotic, and nearly all of the most important human pathogens are either zoonotic or originated as zoonoses before adapting to human transmission , . Hence, wildlife species play a key role in disease emergence by providing a “zoonotic pool” from which previously unknown pathogens may emerge . A major goal of infectious disease research is therefore to characterize those unknown pathogens circulating in animal host reservoirs before they emerge in human populations , .
We describe four novel hantavirus sequences from bats and insectivores captured in China. The hantavirus harbored by three Rhinolophus bats and one carried by the Sorex isodon shrew exhibited ≤89.6% amino acid similarity in the N, GPC and L protein sequences with any recognized hantaviruses, while the hantavirus carried by one Pipistrellus bat shared ≤81.9% amino acid similarity in both the N and L protein sequences with known hantaviruses. The hantavirus found in Anourosorex squamipes (shrew) from Lianghe (Yunnan Province) was most closely related to CBNV also identified in Anourosorex squamipes in Vietnam, but with quite different N (>4.4% amino acid), L (>5.7%), and GPC (>7.3%) amino acid sequences. Interestingly, the mt-cyt b gene differences between Anourosorex squamipes in Yunnan of China and Vietnam are 1.7%, compatible with the existence of the two subspecies of Anourosorex squamipes. According to the criteria for species demarcation in the genus Hantavirus proposed by the International Committee on Taxonomy of Viruses , these four hantaviruses are sufficiently genetically distinct that they should be recognized as distinct species. Accordingly, we propose naming these four novel hantaviruses as Huangpi virus (HUPV), Lianghe virus (LHEV) Longquan virus (LQUV), and Yakeshi virus (YKSV), reflecting their geographic origins. In addition, as LHEV has not been isolated, such that two-way cross neutralization tests cannot be performed, further studies are needed to clarify whether LHEV is a novel species or simply a variant of CBNV. Finally, the identification of LQUV in three Rhinolophus bats also means that hantaviruses may spread relatively easily among different species of bats.