Neutralizing activity against herpes simplex in maternal milk

: Human milk could play a role in the protection of the newborn from Herpes simplex virus 2 contamination. Neutralizing activity against Herpes simplex virus 2 was measured in 94 human milk samples and in 31 sera from healthy women. A weak neutralizing activity was detected in 48 milk samples. They were neither correlated to anti-Herpes simplex virus antibodies found in milk, nor to the neutralizing activity in sera. The origin and non immunologic nature of this activity are discussed.