A detritus exclusion appliance includes a support that is preferably, but not necessarily, constructed of extruded aluminum and that comprises a screen made of surgical grade stainless steel wire mesh that prevents debris from entering rain gutters. The support is preferably formed of an extruded material that includes one or more upwardly projecting support beams. A center beam may project upwardly beyond beams to either side of it to create a curved profile in which the wire mesh is curved along an axis of the support to slope downwardly on either side of the center beam. This arrangement assists in shedding detritus and debris from the screen.