title: The potential impact of pneumococcal conjugate vaccine in Africa: Considerations and early lessons learned from the South African experience.
abstract: The introduction of pneumococcal conjugate vaccine (PCV) into the South African public immunization program since 2009 adopted a novel vaccination schedule of 3 doses at 6, 14 and 40 weeks of age. Over the past 5 y it has been shown that infant PCV immunization in South Africa is effective in reducing the burden of invasive pneumococcal disease (IPD) among HIV-infected and HIV-uninfected children. Furthermore, indirect protection of unvaccinated age-groups (including high risk groups such as HIV-infected adults) against IPD was demonstrated despite the absence of any substantial catch-up campaign of older children. This indirect effect against IPD is corroborated by the temporal reduction in vaccine-serotype colonization among age-groups targeted for PCV immunization as well as unvaccinated HIV-infected and HIV-uninfected adults, which was evident within 2 y of PCV introduction into the immunization program. Vaccine effectiveness has also been demonstrated in children against presumed bacterial pneumonia. The evaluation of the impact of PCV in South Africa, however, remains incomplete. The knowledge gaps remaining include the evaluation of PCV on the incidence of all-cause pneumonia hospitalization among vaccinated and unvaccinated age-groups. Furthermore, ongoing surveillance is required to determine whether there is ongoing replacement disease by non-vaccine serotypes, which could offset the early gains associated with the immunization program in the country.
authors: a Medical Research Council; Respiratory and Meningeal Pathogens Research Unit; University of the Witwatersrand ; Johannesburg , South Africa.|b Department of Science and Technology/National Research Foundation ; Vaccine Preventable Diseases; University of the Witwatersrand ; Johannesburg , South Africa.|c National Institute for Communicable Diseases; National Health Laboratory Service; Center for Vaccines and Immunology ; Johannesburg , South Africa.
authors: Shabir A
authors: SA
authors: Madhi
authors: a Medical Research Council; Respiratory and Meningeal Pathogens Research Unit; University of the Witwatersrand ; Johannesburg , South Africa.|b Department of Science and Technology/National Research Foundation ; Vaccine Preventable Diseases; University of the Witwatersrand ; Johannesburg , South Africa.
authors: Marta C
authors: MC
authors: Nunes
mesh_terms: D002353:Carrier State / Q000382:microbiology* / Q000517:prevention & control; D002675:Child, Preschool; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy* / Q000821:virology; D006801:Humans; D017589:Immunization Programs; D007115:Immunization Schedule; D007223:Infant; D009305:Nasopharynx / Q000382:microbiology*; D022242:Pneumococcal Vaccines / Q000276:immunology*; D011018:Pneumonia, Pneumococcal / Q000453:epidemiology* / Q000517:prevention & control; D013019:South Africa / Q000453:epidemiology; D013296:Streptococcus pneumoniae / Q000276:immunology; D014611:Vaccination; D018074:Vaccines, Conjugate / Q000276:immunology*
chemical_list: D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate
keywords: HIV; South Africa; effectiveness; invasive disease; pneumococcal conjugate vaccine; pneumonia