Author summary Enterotoxigenic Escherichia coli (ETEC) are a significant cause of childhood diarrhea in low-middle income countries for which there is currently no vaccine. ETEC vaccine approaches to date have focused on antigens known as colonization factors (CFs) and the pathovar-defining toxins. However, both antigenic diversity of CFs and the lack of characterized CF antigens in many strains has hindered deployment of broadly protective ETEC vaccines. Nevertheless, more recent studies have identified additional ETEC virulence molecules that could compliment canonical vaccine strategies. Here, we demonstrate that two proteins, the EtpA adhesin and EatA mucinase, are present in a diverse, global collection of isolates, and are among the most highly conserved ETEC pathovar-specific antigens to be identified, providing additional incentive to explore their utility in the rational design of broadly protective ETEC vaccines.