RESUMO
BACKGROUND: Vaccination is considered as the most cost effective method for preventing infectious diseases. Low grade fever is a known adverse effect of vaccination. In India, it is a common clinical practice to prescribe paracetamol either prophylactically or therapeutically to manage fever. Some studies have shown that paracetamol interferes with antibody responses following immunization. This manuscript reports the outcome of a post hoc analysis of data from a clinical trial of a pentavalent vaccine in Indian infants where paracetamol was not used or was used either as prophylaxis or for treatment of fever. METHODS: Pre and post vaccine antibody levels against Diphtheria, Tetanus, Pertussis, Hepatitis B, Haemophilus influenzae type B were assessed in no paracetamol and paracetamol groups. The paracetamol group was further divided into prophylactic and treatment groups. RESULTS: Similar rates of seroprotection/seroresponse for anti-D, anti-T, anti-wP, anti-PT, anti-HBs and anti-PRP were observed in all the groups. There was no clear tendency for difference in percentage seroprotection/seroresponse and geometric mean (GM) titers in any of the groups. CONCLUSION: The study found no evidence that paracetamol usage either as prophylactic or for treatment impact immunological responses to DTwP-HepB-Hib combination vaccine. [Clinical trial registry of India (study registration number CTRI/2012/08/002872)].