STD is also an obsolete term. Epidemiology, Medicine etc. most often now refer to them as STIs, or Sexually Transmitted Infections. The reasoning for this is t

STD is also an obsolete term. Epidemiology, Medicine etc. most often now refer to them as STIs, or Sexually Transmitted Infections. The reasoning for this is that many sexually transmitted infections can be acquired, passed on to others, etc. without causing any clinical symptoms. See: HPV, among others.