A i, Six-week-old mouse was >2 SD below mean weight (white arrow, compared with littermate) weighing only 12.5 g; ii, Brain tissue showed ZIKV positivity (black arrows) by in situ hybridization; iii, No ZIKV was apparent in spleen. B i, Eight-day-old mouse developed hind-limb paralysis and severe growth restriction (white arrow); ii, ZIKV infection present throughout spinal cord (black arrows); iii, Higher-power image showing staining throughout spinal column; iv and v, ZIKV replicating Vero cells and mock infected are positive and negative hybridization controls, respectively; vi, ZIKV polymerase chain reaction from moribund mouse showed significant positivity throughout all tissues assayed (black arrow demonstrates ZIKV band at 74 nucleotides).