I don't feel that ants eat Camellia leaves. The ants are maybe looking for greenfly that secrete a sweet fluid. Whether they are on the Camellia, which is unusual, or some other shrub near to. Also Camellias have to shed leaves even though they are not deciduos. The leaves become discoloured or mishapen or even holed and then drop away. Ants follow a scent trail to get where they find aphids. This may have been laid across the Camellia.

I agree with Dorjac.

I agree as well. The only pest I have seen affect Camellia is Vine weevil and they leave notch marks on the leaves and the grubs eat the roots. That Ants are honestly fine, eating Aphids, so are helping and not attacking as both posts above say.

Check the Camellia all over - the branches, stems, twigs and backs of leaves in particular. You're looking for scale insect (cushion scale) as well as aphids - both produce sticky honeydew that ants like to collect. Treat for scale or aphids, whichever it is, and the ants will disappear. The ants are not, as others have said, damaging your plant directly - but they are 'farming' some other insect pest which will be causing some minor damage.

Note that if it is cushion scale, at this time of year you should see the remains of the egg sacs on the underside of the leaves - these may look mealy. Check the RHS page on cushion scale for more information.

Ok Will Check the underside of the leaves, thank you all, very muchly.
Regards
Peter