For Pam in Zimbabwe: These articles might help:
Goldman AS, Goldblum RM. Immunologic components in human milk during the
second year of lactation. Acta Paediatr Scand 1983. 72:461-462.
Fitzsimmons SP et al. Immunoglobulin A subclasses in infants' saliva and in
saliva and milk from their mothers. The Journal of Pediatrics
1994;124:566-73.
Anne Altshuler, RN, MS, IBCLC and LLL leader in Madison, WI