Q. An 18-month-old boy is brought to the emergency department by his mother for fever and a rash on his left cheek for 2 days. She says that the symptoms started yesterday with a fever and also she observed a red streak on the child’s face. She gave fever reducer syrup and made him sleep. But when the boy woke up in the morning, the rash has spread to the whole cheek extending behind the left year. His birth history shows that he is a full-term normal delivered baby with no complications. He is up-to-date with immunization. His family shows that his elder sister is recently diagnosed with scarlet fever and is on antibiotics now. His temperature is 102°F (38.8°C), pulse is 110/min, blood pressure is 80/60 mmHg, and respirations are 15/min. Physical examination shows an erythematous rash that is a bit raised with sharply defined margins on the left cheek and also involves the left ear. The rash contains some crusting material with a few small vesicles on a diffuse erythematous base. Pre and post-auricular lymph nodes on the left side are enlarged. Rest of the examination is unremarkable. Lab investigations are shown below. What is the most likely diagnosis for this patient based on his clinical features and lab results?