Real-world vaccination status of children with hematologic tumors before and after chemotherapy

Abstract

Background: There is a high incidence and mortality rate in children with hematologic tumors (CHT), who are more prone to various infectious diseases. This study aims to clarify the real-world National Immunization Program (NIP) vaccination status of CHT before and after chemotherapy. Methods: Medical records, NIP vaccination data, and the Adverse Event Following Immunization (AEFI) of CHT who were admitted to the Children’s Hospital, Zhejiang University School of Medicine, from 1 January 2011 to 1 December 2021 were completely collected. Results: A total of 2,874 CHT were included, and 1975 (68.7%) had vaccination records. Among the enrolled patients, the vaccination rate of all NIP vaccines was lower than 90% before diagnosis. Only 24.29% of CHT (410/1688) resumed vaccination after chemotherapy, and 69.02% (283/410) resumed vaccination more than 12 months after chemotherapy. No uncommon or serious side effects were reported. Conclusion: The vaccination rate of CHT after chemotherapy was lower than that before the disease was diagnosed. It is necessary to provide more evidence-based support and formulate specific regimens to perfect the vaccination procedure after chemotherapy so as to improve the quality of life of CHT.