A 10-month-old infant had high fever of 39.5 degrees C for 4 days with no localizing signs and a normal examination. The fever subsided abruptly, and within 24 hours a pink maculopapular rash appeared on the trunk and spread to the face and limbs. The child is playful. What is the causative agent?
- A Coxsackievirus A16
- B Parvovirus B19
- C Human herpesvirus 6 ✓
- D Rubella virus
Correct answer: C. Human herpesvirus 6
Explanation
Roseola infantum (exanthem subitum) is caused by human herpesvirus 6 and classically presents as 3 to 5 days of high fever in an infant aged 6 months to 2 years, followed by defervescence and then a rose-pink maculopapular rash. The appearance of rash only after the fever falls is the discriminating feature, whereas rubella and measles rashes appear during the febrile phase.
Reference: Nelson Textbook of Pediatrics, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.