Immunogenicity following the first and second doses of 7-valent pneumococcal conjugate vaccine in HIV-infected and -uninfected infants

Abstract

Background The immunogenicity of pneumococcal conjugate vaccine (PCV) has not been evaluated in HIV-infected infants following the first and second PCV-doses. We studied antibody kinetics of serotypes included in 7-valent PCV in HIV-infected and HIV-uninfected infants prior to and following each of three PCV-doses. Methods HIV-uninfected infants born to HIV-uninfected (HUU) and HIV-infected mothers (HEU); and perinatal HIV-infected children with CD4+ < 25% randomized to initiate antiretroviral treatment (ART) when clinically and/or immunologically indicated (ART−) or immediately (ART+) were enrolled. Vaccination occurred at approximately 7.4, 11.5 and 15.5 weeks of age. Serotype-specific antibody was measured by ELISA following each PCV-dose and opsonophagocytic activity (OPA) to three serotypes following the second and third doses. Results Pre-vaccination, antibody geometric mean concentrations (GMCs) were higher in HUU compared to HIV-exposed groups for most serotypes. GMCs and proportion of infants with antibody ≥0.35 μg/ml were similar in HUU compared to other groups following the second PCV-dose. In all groups, GMCs were greater following the third compared to post-second dose; and a higher proportion within each group had antibody ≥0.35 μg/ml to 6B and 23F. OPA GMTs increased after the third compared to post-second dose for studied-serotypes; as did the proportion with OPA ≥8 to 23F. Conclusion A two-dose primary-series of PCV probably confers similar protection against invasive pneumococcal disease in HIV-infected compared to HUU children. The inferior response to serotypes 6B and 23F, and lower GMCs and OPA GMTs, following two compared to after three PCV-doses may have implications in the prevention of pneumococcal disease in high-burden countries.

Vaccination with 10-valent pneumococcal conjugate vaccine in infants according to HIV status

“…Immune responses in HIV+ children with percentages of CD4+ cells ≥25% (signifying immuno-competence) have been previously assessed for PCV7; [16,18] higher antibody concentrations were observed post-primary vaccination in HIV+ children on ART than in HUU children, with similar OPA titres (except for 19F and 23F). [16] …”

Longitudinal study on Streptococcus pneumoniae, Haemophilus influenzae and Staphylococcus aureus nasopharyngeal colonization in HIV-infected and -uninfected infants vaccinated with pneumococcal conjugate vaccine

“…Prevnar®; Wyeth Vaccines, NJ, USA), administered at 6, 10 and 14 weeks of age was evaluated. [15, 16] Briefly, PCV7 was administered concurrently with other recommended childhood vaccines in South Africa, including H. influenzae type-b conjugate vaccine (HibCV). Infants were enrolled in Soweto (Gauteng) and Tygerberg (Western Cape) in South Africa from April 2005 to June 2006.…”

Effectiveness of pneumococcal conjugate vaccine and rotavirus vaccine introduction into the South African public immunisation programme

“…The immune responses following two doses of PCV given at 6 and 10 weeks of age were, however, similar in HIV-infected SA infants on ART compared with HIV-uninfected SA infants. [25] Furthermore, provisional results of a case-control study also showed that PCV-immunised, HIV-uninfected children were 27% (95% CI 0 -49) less likely than unimmunised children to be hospitalised for presumed bacterial pneumonia. [26] A multi-centre, case-control study to evaluate the effectiveness of RV against rotavirus-associated diarrhoea hospitalisation is also nearing completion.…”