Which infection is described by a 'slapped cheek' rash pattern in children?

• A. Parvovirus B19 infection (fifth disease/erythema infectiosum)
• B. Rubella
• C. Varicella
• D. Adenovirus

Answer: (A)

The facial redness described as a “slapped cheek” pattern is classic for Parvovirus B19 infection, known as fifth disease or erythema infectiosum. In children, the illness often starts with mild fever and malaise, then the cheeks become intensely red, giving the slapped-cheek appearance. A few days later, a lacy, reticular rash may appear on the trunk and limbs as the facial redness fades. The rash results from the virus’s effect on red blood cell precursors and immune-mediated changes in the skin. It’s contagious before the rash appears, and while it’s usually mild, Parvovirus B19 can cause complications in people with certain anemias and, if a pregnant woman is infected early in pregnancy, can lead to hydrops fetalis.

Other infections present with different rashes: rubella typically has a fine maculopapular rash with prominent postauricular lymphadenopathy; varicella shows crops of vesicular lesions in various stages; adenovirus often involves respiratory symptoms or conjunctivitis rather than a slapped-cheek facial rash.