RT Journal Article
SR Electronic
T1 Rapid evolution of enhanced Zika virus virulence during direct vertebrate transmission chains
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.10.23.353003
DO 10.1101/2020.10.23.353003
A1 Kasen K. Riemersma
A1 Anna S. Jaeger
A1 Chelsea M. Crooks
A1 Katarina M. Braun
A1 James Weger-Lucarelli
A1 Gregory D. Ebel
A1 Thomas C. Friedrich
A1 Matthew T. Aliota
YR 2020
UL http://biorxiv.org/content/early/2020/10/23/2020.10.23.353003.abstract
AB Zika virus (ZIKV) has the unusual capacity to circumvent natural alternating mosquito-human transmission and be directly transmitted human-to-human via sexual and vertical routes. The impact of direct transmission on ZIKV evolution and adaptation to vertebrate hosts is unknown. Here we show that molecularly barcoded ZIKV rapidly adapted to a mammalian host during direct transmission chains in mice, coincident with the emergence of an amino acid substitution previously shown to enhance virulence. In contrast, little to no adaptation of ZIKV to mice was observed following chains of direct transmission in mosquitoes or alternating host transmission. Detailed genetic analyses revealed that ZIKV evolution in mice was generally more convergent and subjected to more relaxed purifying selection than in mosquitoes or alternate passages. These findings suggest that prevention of direct human transmission chains may be paramount to resist gains in ZIKV virulence.Competing Interest StatementThe authors have declared no competing interest.