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Published on: September 23, 2022
A randomized study of fever prophylaxis and the immunogenicity of routine pediatric vaccinations
Jacek Wysocki1, Kimberly J Center2, Jerzy Brzostek3
1Department of Preventive Medicine, Poznań University of Medical Sciences, ul. Smoluchowskiego 11, 60-179 Poznań, Poland.
Insights
Routine use of prophylactic antipyretics like paracetamol or ibuprofen during infant vaccination may impact immune responses. Paracetamol reduced pneumococcal antibody levels, while ibuprofen affected pertussis and tetanus responses.
Area of Science:
- Pediatric immunology
- Vaccinology
- Pharmacology
Background:
- Prophylactic antipyretic use is common in infants during vaccination.
- Concerns exist regarding potential interference with vaccine-induced immune responses.
Purpose of the Study:
- To evaluate the impact of prophylactic paracetamol and ibuprofen on immune responses to the 13-valent pneumococcal conjugate vaccine (PCV13) and a combined DTaP/HBV/IPV/Hib vaccine in infants.
- To assess if antipyretic administration timing influences these immune responses.
Main Methods:
- Infants received prophylactic paracetamol or ibuprofen at specific intervals post-vaccination.
- Immune responses to PCV13 and DTaP/HBV/IPV/Hib vaccines were measured at 5 and 13 months of age.
- Responses were compared between antipyretic groups and a no-prophylaxis control group.
Main Results:
- Paracetamol prophylaxis, especially when initiated at vaccination, led to significantly lower pneumococcal anticapsular immunoglobulin G levels for five serotypes.
- Ibuprofen did not affect pneumococcal responses but reduced antibody responses to pertussis and tetanus antigens.
- No significant differences in immune responses were observed after the toddler vaccine dose for any group.
Conclusions:
- Prophylactic antipyretics can alter vaccine immune responses, with effects varying by agent, vaccine, and administration timing.
- Paracetamol may dampen infant immune responses to pneumococcal antigens, while ibuprofen may affect responses to pertussis and tetanus antigens.
- The use of antipyretics for fever prophylaxis during infant vaccination warrants careful consideration due to potential immunomodulatory effects.
Objective:
Prophylactic antipyretic use during pediatric vaccination is common. This study assessed whether paracetamol or ibuprofen prophylaxis interfere with immune responses to the 13-valent pneumococcal conjugate vaccine (PCV13) given concomitantly with the combined DTaP/HBV/IPV/Hib vaccine.
Methods:
Subjects received prophylactic paracetamol or ibuprofen at 0, 6-8, and 12-16 h after vaccination, or 6-8 and 12-16 h after vaccination at 2, 3, 4, and 12months of age. At 5 and 13months, immune responses were evaluated versus responses in controls who received no prophylaxis.
Results:
After the infant series, paracetamol recipients had lower levels of circulating serotype-specific pneumococcal anticapsular immunoglobulin G than controls, reaching significance (P<0.0125) for 5 serotypes (serotypes 3, 4, 5, 6B, and 23F) when paracetamol was started at vaccination. Opsonophagocytic activity assay (OPA) results were similar between groups. Ibuprofen did not affect pneumococcal responses, but significantly (P<0.0125) reduced antibody responses to pertussis filamentous hemagglutinin and tetanus antigens after the infant series when started at vaccination. No differences were observed for any group after the toddler dose.
Conclusions:
Prophylactic antipyretics affect immune responses to vaccines; these effects vary depending on the vaccine, antipyretic agent, and time of administration. In infants, paracetamol may interfere with immune responses to pneumococcal antigens, and ibuprofen may reduce responses to pertussis and tetanus antigens. The use of antipyretics for fever prophylaxis during infant vaccination merits careful consideration. ClinicalTrials.gov identifier: NCT01392378https://clinicaltrials.gov/ct2/show/NCT01392378?term=NCT01392378&rank=1.
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