Compared to our previous studies of primary RhCMV infection in the setting of CD4 + T lymphocyte depletion (16, 17), all dams in this cohort had reduced risk of vertical transmission (41.6% AF + vs 100% AF + in CD4-depleted dams) and carried to elective C-section with no incidence of spontaneous abortion (100% vs 16.7% fetal survival in CD4-depleted dams) (Fig. S4A-B). The gene discussed is CD4; the disease is abortion.