Clearly, the ability to produce parasite antigens through genetically modified micro-organisms has improved the feasibility of some parasitic vaccines. However, producing protective recombinant parasite antigens has proven difficult. Efforts have been inhibited by the fact that recombinant proteins may be incorrectly folded and/or lack critical post-translational modifications, particularly the glycans that are attached to several of the native candidate antigens. This issue is a major challenge in vaccine production and has been discussed recently (10).