I agree, Micro Made Ridiculously Simple along with First Aid for USMLE, will take care of all your micro needs. In the beginning I went with Micro & Immuno (Levinson/Jawetz), but found it too detail and difficult to sort/memorize. However MMRS is a really funny book and the diagrams stick in you head more readily. Your best bet would be to browse this book, it should be in your med school library, or just ask some of your classmates. Alright, later.🙂