Lack of prophylactic efficacy of an enteric-coated bovine hyperimmune milkproduct against enterotoxigenic Escherichia coli challenge administered during a standard meal

Orally administered bovine immunoglobulins with specific activity against c olonization factors of enterotoxigenic Escherichia coli (ETEC) could provid e passive protection against ETEC challenge in volunteers. Twenty healthy a dult volunteers ingested either a placebo or a partially enteric-coated pre paration of bovine immunoglobulins with activity against the colonization f actor antigens CFA/I, CS3, and CS6 and then were challenged with ETEC strai n E24377A (CS1(+), CS3(+)) administered with a standard meal. There was no difference in the incidence or severity of diarrhea among the 10 volunteers who received the bovine immunoglobulins and the 10 who received placebo. E ither the specificity or titer of anti-colonization factor antibodies or th e formulation of antibodies in this product was not adequate to provide pas sive protection against ETEC challenge.