*The horse should be resident in or have travelled within the Americas<ref name="EPM3">Vatistas, N, Mayhew, J (1995) Differential diagnosis of polyneuritis equi. ''In Practice'', Jan, 26-29.</ref> | *The horse should be resident in or have travelled within the Americas<ref name="EPM3">Vatistas, N, Mayhew, J (1995) Differential diagnosis of polyneuritis equi. ''In Practice'', Jan, 26-29.</ref> |