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Published on: December 1, 2017
Comparison of immunogenicity and reactogenicity of split versus subunit influenza vaccine in Korean children aged
Yun Kyung Kim1, Byung Wook Eun, Nam Hee Kim
1Department of Pediatrics, Korea University College of Medicine, Seoul, Korea.
Insights
The split (SPL) influenza vaccine showed better immunogenicity than the subunit (SU) vaccine in Korean children aged 6-35 months. Both vaccines were safe and well-tolerated, with no significant differences in adverse events.
Area of Science:
- Pediatrics
- Immunology
- Vaccinology
Background:
- Limited data exist on the immunogenicity and reactogenicity of subunit (SU) versus split (SPL) influenza vaccines in Asian children.
- A study was conducted in 2008 to evaluate these aspects in Korean children aged 6-35 months.
Purpose of the Study:
- To compare the immunogenicity and safety of trivalent inactivated SU and SPL influenza vaccines in young children.
- To determine if the SPL vaccine elicits a superior immune response compared to the SU vaccine.
Main Methods:
- A non-randomized, open-label, controlled trial involving two cohorts of children who received either SU or SPL vaccine.
- Antibody titers were measured using a hemagglutination-inhibition assay before and 30 days after vaccination.
- Immunogenicity was assessed based on European Union licensing criteria.
Main Results:
- The split (SPL) vaccine group demonstrated higher seropositivity rates against H1N1 (87.2%), H3N2 (85.1%), and B (70.2%) compared to the subunit (SU) vaccine group (71.2%, 57.6%, 37.3%, respectively).
- Post-vaccination geometric mean titers were significantly higher for all strains in the SPL group compared to the SU group.
- No serious vaccine-related adverse events were reported, and both vaccines exhibited similar safety profiles.
Conclusions:
- The split (SPL) influenza vaccine demonstrates superior immunogenicity compared to the subunit (SU) vaccine in Korean children aged 6-35 months.
- Both SPL and SU influenza vaccines are safe and well-tolerated in this pediatric population.
Background:
Studies comparing the immunogenicity and reactogenicity of trivalent inactivated subunit (SU) and split (SPL) vaccines in children in Asia are limited. In 2008, we assessed the safety and immunogenicity of SU and SPL influenza vaccines in Korean children aged 6-35 months.
Methods:
We studied 2 non-randomized cohorts of children who received either SU or SPL vaccine in an open-label non-stratified controlled trial at 6 hospitals in Korea. We measured antibody titers with a hemagglutination-inhibition assay at baseline and 30 days after the first or second flu shot. The primary goal was the determination of vaccine immunogenicity according to the European Union Committee of Human Medicinal Products licensing criteria.
Results:
Out of a total of 106 participants aged 6-35 months, 47 received the SPL vaccine and 59 the SU vaccine. After vaccination, 41 (87.2%), 40 (85.1%), and 33 (70.2%) of the 47 subjects in the SPL group had titers ≥ 1:40 against H1N1, H3N2, and B, respectively. In the SU group, 42 (71.2%), 34 (57.6%), and 22 (37.3%) of 59 subjects had titers ≥ 1:40 against H1N1, H3N2, and B, respectively. The post-vaccination geometric mean titers of H1N1, H3N2, and B (SPL vs SU) were 119.1, 99.8, and 61.4 vs 75.4, 51.2, and 24.1, respectively. There were no serious vaccine-related adverse events. There were no differences between the SPL and SU vaccines with respect to adverse events.
Conclusions:
The immunogenicity of the SPL vaccine appears to be better than that of the SU vaccine in children aged 6-35 months in Korea.
