Vaccine Immune Recovery After Leukemia

This observational study aims to assess recovery of the immune system and immunity to vaccine-preventable diseases in children and adolescents who recently completed treatment for acute lymphoblastic leukemia (ALL). Several children's hospitals in the United States are participating in the study, which will enroll approximately 75 pediatric participants. The study is intended to determine the rate of infection after leukemia treatment and to inform future studies and recommendations about whether children and adolescents who have leukemia should receive additional vaccine doses or boosters after treatment.

Inclusion Criteria:Children diagnosed with B or T ALL at age 12 months or olderCompleted ALL chemotherapy within the past three months or will complete ALL chemotherapy in the upcoming three monthsThree years of age or older at time of enrollmentExclusion Criteria:Diagnosis of infant ALLEvidence of disease relapseHistory of primary immunodeficiency (except related to Down Syndrome)History of a stem cell transplant or cellular immunotherapyHistory of prior malignancy or condition requiring chemotherapy other than for current ALL diagnosis