Do a search on collegeboard.com for schools that offer a major in microbiology (or sometimes, listed as bacteriology). You'll find quite a few schools that offer a major in it. At some other schools with a biology major, microbiology may be a specialized track within the major. At the undergrad level, you are somewhat more likely to find a specialized major in microbiology at the various landgrant state universities, especially in the Colleges of Agriculture.
The American Society for Microbiology lists curriculum recommendations for microbiology majors here:
ASM's Curriculum Recommendations: Microbiology Majors Program