• Fifth's disease is a viral infection caused by the human parvovirus B19.
• It is a mildly contagious disease of childhood that tends to affect children ages 3 to 12.
• Its incubation period is 6 to 14 days.
• Fifth's disease has three distinct stages:
- First a red blush or sunburned looking rash appears over both cheeks.
- The next day, red round spots appear on the arms and legs.
- About one week later the first rash fades, causing a lacy marble-like pattern to appear.
• The lacy looking rash is the characteristic finding of this disease.
• The rash may last up to a month and may frequently disappear and then reappear.
• Generally the child feels well and has no fever.
• The diagnosis is usually made clinically; however, a blood test can be done for parvovirus B19.
• Children who have the lacy rash are not contagious by this stage and may attend school.
Note: This virus can be especially dangerous to fetuses. If you are pregnant and have been exposed to this virus, alert your obstetrician so they can adequately monitor your pregnancy.
Find out about other rashes: