Do universities know that you have re-applied Do universities know that you are a re-applicant who applied to the same program last year? Do they keep that database? And if they do, does that hurt your chances? (Specific to universities in the US and the UK)
Do universities know that you are a re-applicant who applied to the
  same program last year?


Yes, they do. Moreover, many universities directly ask are you a re-applicant in application forms.