Mulumbu is set to be away with DR Congo between 17 January to 8 February when the tournament takes place in Equatorial Guinea.
"It is a position where we have got a lot of players," explained Irvine.
"We are probably stronger in terms of our options in midfield than elsewhere so if we do lose Youssouf then it may not be necessary for us to bring someone in.
"And it may not be possible for us to bring someone in of the right level anyway, so I'm certainly not looking at the moment in terms of replacing Youssouf."
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