Interferon administered orally: protection of neonatal mice from lethal virus challenge.

Interferon was identified in the milk of mice injected with an interferon inducer. The kinetics of interferon appearance in serum and in milk were similar, but maximum concentrations in milk were 10 to 20 percent of those in serum. Interferon administered orally to neonatal mice was detected in their serums. Significantly more newborns survived an oral challenge with vesicular stomatitis virus when interferon had been induced in the lactating mothers.