The promising malaria vaccine candidates that have been tested in the field
have, so far, yielded disappointing and, at times, conflicting results. Co
nsiderable efforts are being made to isolate new immunogenic molecules. How
ever, the fact that most populations in malaria endemic areas are also infe
cted by helminths appears to be overlooked. Helminth-related hyporesponsive
ness to tetanus or cholera vaccines, and the interactions between malaria p
arasites and helminths, raise the possibility that a potent malaria vaccine
will not be identified in helminth-infected populations, thus necessitatin
g a change in vaccine trial design.