Efrem was born in Limassol and began his career as a 15-year-old with Arsenal in 2004; he was a regular in their reserve and youth sides.

[5] He made his APOEL debut against HJK Helsinki at Sonera Stadium on 30 July 2014, in a 2–2 first leg draw for the third qualifying round of the 2014–15 UEFA Champions League.

[7] Efrem also appeared in five group stage matches in APOEL's 2014–15 UEFA Champions League campaign.

[9][10] Four days later, Efrem celebrated the double with APOEL, as his team beat 4–2 Ermis Aradippou and secured their third consecutive championship title.

The next season, he scored three times in APOEL's impressive run to the last 16 of the 2016–17 UEFA Europa League, opening the score in the away matches against Young Boys and FC Astana for the group stage and against Athletic Bilbao at San Mamés for the round of 32 of the competition.