We calculate the 2nd and 4th order quark number susceptibilities at zero baryochemical potential, using a PNJL approach and an approach which includes, in a single model, quark and hadronic degrees of freedom. We observe that the susceptibilities are very sensitive to possible quark-quark vector interactions. Compared to lattice data our results suggest that above T_c any mean field type of repulsive vector interaction can be excluded from model calculations. Below T_c our results show only

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... weak sensitivity on the strength of the quark and hadronic vector interaction. The best description of lattice data around T_c is obtained for a case of coexistence of hadronic and quark degrees of freedom.