TABLE 1.
Potential factors contributing to the recent emergence of Zika virus (ZIKV).
| Potential factors | Description | References | |
| Pathogen | |||
| Mutation | prM-S139N | prM-S139N mutant causes a more severe microcephalic phenotype with a thinner cortex, more robust brain cell apoptosis, and more NPC differentiation disruption in mice | Yuan et al., 2017 |
| Mutation | NS1-A982V | NS1-A982V mutation enhances ZIKV transmission in a mosquito-mouse-mosquito transmission cycle | Liu et al., 2017 |
| NS1-A982V mutation of ZIKV enhances the inhibition of interferon-beta production | Xia et al., 2018 | ||
| Mutation | E-V763M | E-V763M mutation increases ZIKV replication, neurovirulence in neonatal mice, and maternal-to-fetal transmission | Shan et al., 2020 |
| Mutation | C-T106A, prM-V123A, NS1-A982V, and NS5-M3392V | ZIKV with C-T106A, prM-V123A, NS1-A982V, and NS5-M3392V mutations has a fitness advantage | Liu et al., 2021 |
| Host | |||
| Genetics | Host genome background | The pathogenesis of discordant and dizygotic twins from ZIKV-infected mothers was compared, and host genetics was found to substantially affect the severity of a ZIKV infection, even when infected with the same strain | Caires-Junior et al., 2018 |
| Immunity | Preexisting anti-flavivirus immunity | Previous DENV immunity had no or cross-protection impact against ZIKV infection | Gordon et al., 2019; Rodriguez-Barraquer et al., 2019; Carvalho et al., 2020 |
| Environment | |||
| Temperature | Climate change | Elevated temperatures can expand the geographic vector range, decrease the extrinsic incubation period of the pathogen, and increase the female mosquito biting rate | Morin et al., 2013; Paz and Semenza, 2016 |
prM-S139N, S139N mutation in the pre-membrane (prM) coding region; NS1-A982V, A982V mutation in the non-structural protein 1 (NS1) coding region; E-V763M, V763M mutation in the envelope (E) coding region; C-T106A, T106A mutation in the capsid (C) coding region; prM-V123A, V123A mutation in the pre-membrane (prM) coding region; NS5-M3392V, M3392V mutation in the non-structural protein 5 (NS5) coding region; DENV, Dengue virus; ZIKV, Zika virus.