SOX2 and infection: Both SOX2 expression level (s) and virus bursting size (b) play an important role in OVT since (1) SOX2 expression levels activate the membrane receptor αvβ5, which results in an enhancing of the infection rate of ZIKV into GSCs and (2) the virus bursting size is directly proportional to the basic reproduction number R0, which can change the stability of equilibrium points and affect the efficacy of the therapy.