Symptoms of a more serious infection in the diaper area may include:

• Increased pain, swelling, heat, or redness around the rash.
• A fever.
• Clear, fluid-filled blisters that leave red, raw areas when they break open.
• Pus in or draining from the rash.
• Being fussy, upset, and hard to console.

These symptoms usually last more than 2 days (48 hours) without getting better. A milder diaper rash usually will start to improve sooner.