Viral CpG content affects compartment-specific infection

To better understand the potential safety risks of CpG-recoded live vaccines, we studied infection phenotypes of the recoded neurotropic and congenital Zika virus, in the target tissues: the brain and placenta. While overall infection kinetics were comparable between wild-type and recoded virus variants, we found convergent phenotypical differences characterized by reduced pathology in the mouse brain and reduced replication of CpG-enriched variants in fetal lymph nodes. Altogether, our study emphasized further directions to fine-tune the CpG recoding vaccine approach for better safety and can inform future immunization strategies.