The actress's ditzy character is expected to be brought back to the forefront of the show over the next few weeks as bosses introduce newcomer Father Francis, who tests Carmel's commitment to life as a nun.
Merna told the Daily Star: "I love playing Carmel. I still can't believe that it's been nearly five years since I started. It's gone so quickly but I'm still enjoying it as much as ever. I've got no plans to go anywhere.
"Carmel has got loads of exciting things coming up and she's a great character to play. I still feel very lucky to be a McQueen."
Speaking of the current atmosphere at Hollyoaks, she added: "The soap has gone through a bit of a transitional period over the last year, but I think it's definitely back on track again. The morale is really good and it's an amazing place to work."
Father Francis, played by actor and dancer Richard Winsor, makes his debut on screen in next week's episodes.
Alex Carter (Lee Hunter), Dean Aspen (Duncan Button), Ashley Margolis (Ricky Campbell) and Sikander Malik (Jamil Fadel) have all recently announced that they will be leaving Hollyoaks later this year.
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