Why is it that the line of treatment for a genetic disease is different from infectious diseases?

The line of treatment for a genetic disease is different from infectious diseases as the genetic disease requires a change or alteration in the gene instead of any part or organ. Thus, genetic diseases require treatment of the genome by methods like gene therapy which is generally carried out at the embryo stage or early infant stages. These genetic diseases are not caused by any pathogens unlike infectious diseases and therefore, they require a different line of treatment.