Immunogenicity of a two-dose regime of varicella vaccine in children with cancers.

Abstract

OBJECTIVE:

Live-attenuated varicella vaccine is effective and safe in immunocompetent children. In this study, we assess the immunogenicity and adverse events following varicella vaccination in immunosuppressed cancer children.

METHODS:

Varicella-zoster virus (VZV)-seronegative cancer children received two doses of live-attenuated VZV vaccine (Varilrix) in a span of 3 months. Patients with acute lymphoblastic leukaemia (ALL) were in the maintenance phase of chemotherapy, whereas those with solid tumours joined the study around 3-6 months from treatment discontinuation. VZV-specific cellular and humoral immune responses were measured before and after VZV vaccination.

RESULTS:

The median (range) age of the 17 patients was 4.4 yr (2.0-14.5). Thirteen had ALL, one had myelodysplastic syndrome and three had solid tumours. Following vaccination, the VZV-specific stimulation index (SI) increased from 1.7 (0.9-2.9) to 17.9 (5.9-36.0) (P < 0.001). Similarly, SI to phytohaemagglutinin mitogen increased from 1136 (499-1930) to 1714 (848-2518) (P = 0.028). There were also significant increases in CD4+ cells and CD4:CD8 ratio as well as a reduction in CD16/56+ cells in peripheral blood lymphocytes. Seroconversion rate to VZV was 19% after one dose and increased to 94% after the second dose of VZV vaccine. Serum VZV-specific IgG concentrations also increased significantly following two doses when compared with one dose of VZV vaccine (P = 0.0004). One subject developed possibly vaccine-related chickenpox with self-limiting hepatitis at 5 wk following vaccination. None of the patients developed herpes-zoster at a median (range) follow-up of 27.5 months (24.0-30.0).

CONCLUSIONS:

Non-immune cancer children can be effectively vaccinated against chickenpox at the defined period. However, the safety of chickenpox vaccine in these immunosuppressed children needs to be further studied.

• Authors: Ting-Fan Leung, Chi-Kong Li, Emily C W Hung, Paul K S Chan, Chi-Wai Mo, Raymond P O Wong, Ki-Wai Chik
• Journal: European journal of haematology (Eur J Haematol) Vol. 72 Issue 5 Pg. 353-7 (May 2004) ISSN: 0902-4441 [Print] England
• PMID: 15059071 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright Blackwell Munksgaard 2004.

Chemical References

• Antibodies, Viral
• Chickenpox Vaccine
• Vaccines, Attenuated

Topics

• Adolescent
• Antibodies, Viral (biosynthesis)
• Chickenpox (etiology, prevention & control)
• Chickenpox Vaccine (administration & dosage, adverse effects, immunology)
• Child
• Child, Preschool
• Female
• Fever (etiology)
• Herpesvirus 3, Human (immunology)
• Humans
• Immunity, Cellular
• Immunization Schedule
• Immunocompromised Host
• Lymphocyte Activation
• Male
• Neoplasms (immunology)
• Safety
• Vaccines, Attenuated (administration & dosage, immunology)