A newborn infant has multiple hemorrhagic, cutaneous lesions and does not respond to sound stimuli. Head CT scan shows periventricular calcifications. Which of the following infectious agents is the most likely cause of this child's presentation?

The infectious agents listed are all impoant causes of congenital disease. The triad of cutaneous hemorrhages ("blueberry muffin baby"), deafness, and periventricular CNS calcifications suggests congenital CMV infection, the most common cause of intrauterine fetal viral infection. Other manifestations include microcephaly and hepatosplenomegaly. Neonatal herpes may be congenital, but more commonly is acquired during vaginal delivery. The infection is characterized by vesicles on the skin and mucous membranes, encephalitis, or disseminated disease. Congenital rubella can cause mental retardation, hea abnormalities, blindness, encephalitis, and motor abnormalities. Congenital syphilis can cause death in utero, or a variety of problems including abnormal teeth, bones, and central nervous system.