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The presence of current singularities in a quasisymmetric magnetic field isexplored. Quasisymmetry is shown effective in isolating Pfirsch-Schl\"{u}tersingularities, to leading order, to a single magnetic surface resonant with thehelicity of the symmetry. The effects of pressure driven currents are analysed,indicating that exclusion of this surface from the plasma volume reduces thepotential opening of islands, but does not generally eliminate them completelydue to higher order asymmetric geometric effects. These three-dimensionaleffects are contained in quasisymmetry and indicate the complexity of findingconsistent solutions and their potential sensitivity. The $\delta$-functioncurrent singularities show a distinct quasisymmetric behaviour only when thehigher-order Fourier content of $B$ is relevant for the resistive stabilityparameter $D_R$ (not included in leading-order near-axis expansions). In suchscenarios, quasisymmetry proves advantageous, both in simplicity and avoidanceof amplification by low-order rational surfaces.

Islands and current singularities in quasisymmetric toroidal plasmas