 Upper respiratory tract is the portal of virus entry and primary site of replication Gluck et al., 1994; Muszkat et al., 2000. Thus the importance of the presence of effective mucosal antibodies at the entry site of virus is essential to neutralize the virus and prevent infection Meitin et al., 1994. Secretory IgA sIgA is the primary mucosal antibody, accounting for 70 of the bodys total antibody production Brandtzaeg, 1994. sIgA has been shown to mediate nasal anti-influenza mucosal immunity Renegar Small, 1991 and therefore indicates the importance of vaccination strategies that trigger specific antibody production at mucosal surfaces as well as the importance of dietary nutrients to trigger the release of mucosal neuropeptides necessary for maintenance of the mucosal immune system Renegar et al., 2001. A number of clinical trials examined the effect of vitamin A supplementation in humans on indicators of mucosal immunity. Supplementation to human immunodeficiency virus infected pregnant women is associated with improved gut permeability in their infants at 14 weeks as measured by lactulosemannitol LM urinary excretion test Filteau et al., 1999. While vitamin A supplementation during pregnancy Semba et al., 1999 or the early postpartum period Filteau et al., 2001 show no effect on total sIgA in breast milk, rather vitamin A in milk has been shown to inhibit the growth of both enveloped and non-enveloped viruses Clarke May, 2000. However, total sIgA level of vitamin A-sufficient children has been detected significantly higher than that of vitamin A-deficient children Lin et al., 2007. In animal model, vitamin A supplementation increases both total and antigen specific sIgA-containing cells in the mucosa, which in turn improves the survival rate Nikawa et al., 2001 During early infancy breast milk is the predominant source of vitamin A and to date no study investigates the effect of prenatal vitamin A supplementation and vaccination on the vaccine specific mucosal sIgA responses in offspring. Although maternal IgA is not transplacentally transferred to the infants, but increased vitamin A and vaccine specific sIgA in breast milk as a result of maternal vitamin A supplementation may enhance infants nasal sIgA responses that in turn may provide improved passive protection among young infants. 