Keywords:
S. pneumonia ; Papua New Guinea; antibodies; carriage; pneumococcal conjugate vaccine
Abstract:
Background: There are little data on the immunogenicity of PCV10 and PCV13 in the same high-risk population. Methods: PCV10 and PCV13 were studied head-to-head in a randomized controlled trial in Papua New Guinea in which 262 infants received three doses of PCV10 or PCV13 at 1, 2, and 3 months of age. Serotype-specific IgG concentrations, and pneumococcal and non-typeable Haemophilus influenzae (NTHi) carriage were assessed pre-vaccination, and at 4 and 9 months of age. Infants were followed for safety until 9 months of age. Results: One month after the third dose of PCV10 or PCV13, >80% of infants had IgG concentrations >/=0.35microg/mL for vaccine serotypes, and six months post-vaccination IgG concentrations >/=0.35microg/mL were maintained for 8/10 shared PCV serotypes in >75% of children vaccinated with either PCV10 or PCV13. . Children carried a total of 65 different pneumococcal serotypes (plus nonserotypeable). At 4 months of age, 92% (95% confidence interval (CI) 85-96) of children vaccinated with PCV10 and 81% (95% 72-88) vaccinated with PCV13 were pneumococcal carriers (p = 0.023), while no differences were seen at 9 months of age, or for NTHi carriage. Both vaccines were well tolerated and not associated with serious adverse events. Conclusions: Infant vaccination with 3 doses of PCV10 or PCV13 is safe and immunogenic in a highly endemic setting; however, to significantly reduce pneumococcal disease in these settings, PCVs with broader serotype coverage and potency to reduce pneumococcal carriage are needed.