Upper respiratory tract infections are caused by viruses or bacteria that infect the nose, sinuses, pharynx, or larynx. They include conditions like the common cold, sinusitis, tonsillitis, laryngitis, and pharyngitis. A nurse will assess symptoms, check for signs of infection, monitor breathing, help clear secretions, manage pain, and educate patients on treatment plans and avoiding exacerbating factors. Proper nursing care is important for relieving symptoms and supporting healing from upper respiratory infections.