As described in the materials and methods, in two sets of experiments newborn macaques were immunized shortly after birth via the oral route with replicating SIV vaccines, either VSV-SIV (expressing SIV gag, pol, env) or live-attenuated SIVmac1A11. Booster immunizations on some groups consisted of intramuscular MVA-SIV. The 2nd set of experiments had also a group that received control vectors expressing non-SIV antigens (VSV-HA, expressing influenza hemagglutinine, and MVA-MV expressing measles virus).