Inclusion of multiple immunogens to target a single organism is a strategy being pursued for many experimental vaccines, especially where it is difficult to generate a strongly protective response from a single immunogen. Although there are many human vaccines that contain multiple defined immunogens, in almost every case each component targets a different pathogen. As a consequence, there is little practical experience for deciding where the increased complexity of vaccines with multiple defined immunogens vaccines targeting single pathogens will be justifiable.
Saul, A., & Fay, M. P. (2007). Human immunity and the design of multi-component, single target vaccines. PLoS ONE, 2(9). https://doi.org/10.1371/journal.pone.0000850