The invention provides a filter fabric for providing anti pathogenic properties which has been coated with a composition comprising (a) 0.0001-99.9999% by weight of a compound of such as zinc pyrithione and (b) 0.0001-99.9999% by weight of an additional zinc salt selected from the group consisting of zinc acetate, zinc propionate, zinc oxalate, zinc benzoate, zinc gluconate, zinc ascorbate, zinc citrate, zinc lactate, zinc glycolate, zinc maleate, zinc fumarate, zinc polyacrylate and zinc polymaleate. The invention also provides a composition for imparting anti-viral properties to a breathable substrate material comprising two or more zinc salts selected from the group consisting of zinc acetate, zinc propionate, zinc oxalate, zinc benzoate, zinc gluconate, zinc ascorbate, zinc citrate, zinc lactate, zinc glycolate, zinc maleate, zinc fumarate, zinc EDTA, zinc glycinate, zinc polyacrylate, zinc polylactate, zinc polyglycolate and zinc polymaleate said zinc salts being present in effective amounts to impart anti-pathogenic properties.