Medical microbiology presents a challenge to undergraduate students, mostly due to its extensive content and complexity of unfamiliar terminology. In addition to a narrative review of the literature, we report findings on students' motivation for and approach to learning in the Infections module of an undergraduate medical curriculum, and their perceived lack of retention of knowledge acquired in the module, as determined by a self-administered, anonymous questionnaire. When students experienced information overload, they reverted to performance goals and the wrong motivation for learning. Their focus turned primarily to being successful in tests and examinations, and they consequently adopted a surface approach to learning. Surface learning and memorisation of facts without understanding its content usually result in moderate retention of knowledge, which could handicap the development of clinical reasoning. However, the concern about students' perceived poor retention of knowledge can be laid to rest--the prognosis is not discouraging after all.