Hay fever

Subtilia is an acute seasonal attack of allergic rhinitis. Generally caused by wind pollen, spring type is caused by tree pollen (oak, elm, maple, loquat, birch, cottonwood, olive); summer type is caused by garden grass pollen (dog grass, cattail grass, lemon grass) , Orchard grass, Johnson grass) and weed pollen (Sheep sorrel, English plantain); autumn type is caused by weed pollen (ragweed). Seasonal hay fever couples can be caused by airborne mold spores, so the disease has significant geographic differences.