Complex History of Codiversification and Host Switching of a Newfound Soricid-Borne Orthohantavirus in North America

Abstract

Orthohantaviruses are tightly linked to the ecology and evolutionary history of their mammalian hosts. We hypothesized that in regions with dramatic climate shifts throughout the Quaternary, orthohantavirus diversity and evolution are shaped by dynamic host responses to environmental change through processes such as host isolation, host switching, and reassortment. Jemez Springs virus (JMSV), an orthohantavirus harbored by the dusky shrew (Sorex monticola) and five close relatives distributed widely in western North America, was used to test this hypothesis. Total RNAs, extracted from liver or lung tissue from 164 shrews collected from western North America during 1983–2007, were analyzed for orthohantavirus RNA by reverse transcription polymerase chain reaction (RT-PCR). Phylogenies inferred from the L-, M-, and S-segment sequences of 30 JMSV strains were compared with host mitochondrial cytochrome b. Viral clades largely corresponded to host clades, which were primarily structured by geography and were consistent with hypothesized post-glacial expansion. Despite an overall congruence between host and viral gene phylogenies at deeper scales, phylogenetic signals were recovered that also suggested a complex pattern of host switching and at least one reassortment event in the evolutionary history of JMSV. A fundamental understanding of how orthohantaviruses respond to periods of host population expansion, contraction, and secondary host contact is the key to establishing a framework for both more comprehensive understanding of orthohantavirus evolutionary dynamics and broader insights into host–pathogen systems.

Geographic Distribution and Phylogeny of Soricine Shrew-Borne Seewis Virus and Altai Virus in Russia

“…With the discovery of highly divergent hantaviruses in shrews, moles and bats [ 4 , 5 ], long-held conjectures of the co-evolution of rodent-borne hantaviruses and their hosts have given way to concepts of a far more complex evolutionary history, punctuated by cross-species transmission and host switching [ 6 , 7 , 8 , 9 , 10 , 11 ] and reassortment events [ 12 , 13 , 14 , 15 , 16 , 17 ]. Furthermore, apart from examples of a single hantavirus species being harbored by multiple reservoir host species, certain host species are known to serve as reservoirs of more than one hantavirus species [ 9 , 16 , 18 ].…”

A 19 Year Analysis of Small Mammals Associated with Human Hantavirus Cases in Chile

“…Hantaviruses are known to be transmitted horizontally [21,40], therefore ecological interactions are key to understanding the spread of the virus among reservoir populations. It is also known that a virus may be harbored by two or more species, with higher opportunities for host switch particularly for sympatric species [41,42,43]. Our study shows the importance of conducting long-term studies that cover a large part of the distribution of a pathogen and its hosts, allowing us to infer patterns of infection and the scale of a host’s epidemiologic importance.…”

Human Orthohantavirus disease prevalence and genotype distribution in the U.S., 2008–2020: a retrospective observational study

“…Limited rodent surveillance in national parks, and in connection with human hantavirus cases has begun to elucidate new geographic areas containing hantavirus seropositive rodents. 27 , 30 , 31 , 32 Increased clinician vigilance combined with improved rodent surveillance should yield improved detection of acute human cases.…”