How long does it take for the symptom of herpes to take effect after sex if your partner has it?

Few days to.. A percentage of people that contract herpes never have an outbreak. Or they may become infected, and experience their first outbreak months or years after exposure. After initial exposure, some people experience flu-like symptoms, or they may begin to notice blister formation on the mouth or genitals. So, it varies greatly, and could be from a few days to years!