This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pediatrics
[{'content': 'Fever stops and rash begins is diagnostic of – \nSelect and explain. \nA. Fifth disease, B. Roseola infantum, C. Measles, D. Toxic shock syndrome', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Roseola infantum (Sixth disease or exanthem septum)\n\nIt is caused by human herpesvirus-6 (HSV-6)\nSimilar illness is caused by Parvovirus B-19 and Echovirus.\nAge group involved is 6 mt to 3 yr.\nIncubation period → 5 to 15 days.\n\nClinical manifestations\n\nAbrupt onset with high-grade fever, mild pharyngitis and Coryza.\nThe temperature comes down rapidly in 3 to 4 days when a macular or maculopapular rash appears, starting from the trunk and sometimes extending to the extremities and face.\nThe rash lasts for 24 hours, and disappear in 1-2 days without pigmentation or desquamation.\nThere is occipital and post-auricular lymphadenopathy.', 'role': 'assistant'}]