PATIENT CHARACTERISTICS: Age: 1 to 17 (children only) Performance status: Not specified Life expectancy: At least 3 months Hematopoietic: Not specified Hepatic: Not specified Renal: No dialysis dependency Cardiovascular: No uncontrolled cardiac arrhythmia No hypertension requiring pressor support Pulmonary: No requirement for supplemental oxygen unless expected to resolve within 2 weeks Neurologic: See Disease Characteristics No refractory seizure disorder Other: No detectable human antimouse antibody reactivity if received prior murine antibody preparations No history of ganciclovir allergy or intolerance HIV negative Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception during and for at least 2 months after study