Preferential host switching and its relation with Hantavirus diversification in South America

Abstract

In recent years, the notion of co-speciation between Hantavirus species and their hosts was discarded in favour of a more likely explanation: preferential host switching. However, the relative importance of this last process in shaping the evolutionary history of hantaviruses remains uncertain, given the present limited knowledge not only of virus-host relationships but also of the pathogen and reservoir phylogenies. In South America, more than 25 hantavirus genotypes were detected; several of them act as aetiological agents of hantavirus pulmonary syndrome (HPS). An understanding of the diversity of hantaviruses and of the processes underlying host switching is critical since human cases of HPS are almost exclusively the result of human-host interactions. In this study, we tested if preferential host switching is the main process driving hantavirus diversification in South America, by performing a co-phylogenetic analysis of the viruses and their primary hosts. We also suggest a new level of amino acid divergence to define virus species in the group. Our results indicate that preferential host switching would not be the main process driving virus diversification. The historical geographical proximity among rodent hosts emerges as an alternative hypothesis to be tested.

Habitat, species richness and hantaviruses of sigmodontine rodents within the Interior Atlantic Forest, Paraguay

“…In eastern Paraguay, Uruguay and Brazil, within the Interior Atlantic Forest (IAF), two closely related strains of hantaviruses, Juquitiba (JUQV) and Araucaria (ARAUV), associated with Oligoryzomys nigripes , have been linked to HPS cases in Brazil and Argentina [ 10 , 11 ]. Notably, the mortality associated with ANDV/JUQV and LANV differ with LANV cases showing a lower case fatality (15 versus 40% for ANDV) [ 12 – 15 ]. To our knowledge, no cases of HPS have been associated with Jabora virus (JABV), harbored by Akodon montensis (tribe Akodontini).…”

Estimating pathogen‐spillover risk using host–ectoparasite interactions

“…Nevertheless, recent discoveries on new hosts, new viral strains, and the evolution rate of hantaviruses do not entirely support this idea (Kuhn & Schmaljohn, 2023 ). The possibility of preferential host switching has been proposed but is not supported in hantaviruses in South America, for which geographic proximity is a potential explanation of hantavirus diversification (Rivera et al., 2015 ). Using the known hantavirus hosts in Chile, we found that geographic proximity, phylogenetic relatedness, and centrality in the rodent–ectoparasite network were predictors for rodents being known hantavirus hosts.…”

“…The possibility of preferential host switching has been proposed but is not supported in hantaviruses in South America, for which geographic proximity is a potential explanation of hantavirus diversification (Rivera et al, 2015). (Lobos et al, 2005).…”

“…In Chile, the primary transmission mode for ANDV between rodent species is through saliva, but can also include urine and feces, which are shared when rodents interact (Padula et al., 2004 ). In the case of ANDV, uncovering the ecological factors underlying cross‐species viral transmission could be particularly informative because the mode by which hantaviruses have diversified in South America is still unclear (Kuhn & Schmaljohn, 2023 ; Rivera et al., 2015 ). The limited understanding of hantavirus evolution in South America restricts our capacities to anticipate zoonotic and cross‐species spillover transmission.…”