title: HIV Infection and the Epidemiology of Invasive Pneumococcal Disease (IPD) in South African Adults and Older Children Prior to the Introduction of a Pneumococcal Conjugate Vaccine (PCV).
abstract: BACKGROUND
  Streptococcus pneumoniae is the commonest cause of bacteremic pneumonia among HIV-infected persons. As more countries with high HIV prevalence are implementing infant pneumococcal conjugate vaccine (PCV) programs, we aimed to describe the baseline clinical characteristics of adult invasive pneumococcal disease (IPD) in the pre-PCV era in South Africa in order to interpret potential indirect effects following vaccine use.
  
  
  METHODS
  National, active, laboratory-based surveillance for IPD was conducted in South Africa from 1 January 2003 through 31 December 2008. At 25 enhanced surveillance (ES) hospital sites, clinical data, including HIV serostatus, were collected from IPD patients ≥ 5 years of age. We compared the clinical characteristics of individuals with IPD in those HIV-infected and -uninfected using multivariable analysis. PCV was introduced into the routine South African Expanded Program on Immunization (EPI) in 2009.
  
  
  RESULTS
  In South Africa, from 2003-2008, 17 604 cases of IPD occurred amongst persons ≥ 5 years of age, with an average incidence of 7 cases per 100 000 person-years. Against a national HIV-prevalence of 18%, 89% (4190/4734) of IPD patients from ES sites were HIV-infected. IPD incidence in HIV-infected individuals is 43 times higher than in HIV-uninfected persons (52 per 100 000 vs. 1.2 per 100 000), with a peak in the HIV-infected elderly population of 237 per 100 000 persons. Most HIV-infected individuals presented with bacteremia (74%, 3 091/4 190). HIV-uninfected individuals were older; and had more chronic conditions (excluding HIV) than HIV-infected persons (39% (210/544) vs. 19% (790/4190), p<0.001). During the pre-PCV immunization era in South Africa, 71% of serotypes amongst HIV-infected persons were covered by PCV13 vs. 73% amongst HIV-uninfected persons, p = 0.4, OR 0.9 (CI 0.7-1.1).
  
  
  CONCLUSIONS
  Seventy to eighty-five percent of adult IPD in the pre-PCV era were vaccine serotypes and 93% of cases had recognized risk factors (including HIV-infection) for pneumococcal vaccination. These data describe the epidemiology of IPD amongst HIV-infected and -uninfected adults during the pre-PCV era and provide a robust baseline to calculate the indirect effect of PCV in future studies.
authors: Division of Public Health Surveillance and Response, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa.
authors: Susan
authors: S
authors: Meiring
authors: Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, a division of the National Health Laboratory Service, Johannesburg, South Africa.|School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors: Cheryl
authors: C
authors: Cohen
authors: Division of Public Health Surveillance and Response, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa.
authors: Vanessa
authors: V
authors: Quan
authors: Division of Public Health Surveillance and Response, National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa.
authors: Linda
authors: L
authors: de Gouveia
authors: Division of Pulmonology, Department of Internal Medicine, Charlotte Maxeke Johannesburg Academic Hospital and Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
authors: Charles
authors: C
authors: Feldman
authors: Department of Internal Medicine, Chris Hani Baragwanath Academic Hospital, Johannesburg, South Africa.
authors: Alan
authors: A
authors: Karstaedt
authors: Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, a division of the National Health Laboratory Service, Johannesburg, South Africa.|Department of Global Health, Hubert School of Public Health, Emory University, Atlanta, GA, United States of America.
authors: Keith P
authors: KP
authors: Klugman
authors: Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, a division of the National Health Laboratory Service, Johannesburg, South Africa.|Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, School of Pathology, University of the Witwatersrand, Johannesburg, South Africa.|Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa.
authors: Shabir A
authors: SA
authors: Madhi
authors: Department of Pediatric Medicine, Tygerberg Hospital, Cape Town, South Africa.
authors: Helene
authors: H
authors: Rabie
authors: Centre for Opportunistic, Tropical and Hospital-associated Infections, National Institute for Communicable Diseases, a division of the National Health Laboratory Service, Johannesburg, South Africa.
authors: Charlotte
authors: C
authors: Sriruttan
authors: Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, a division of the National Health Laboratory Service, Johannesburg, South Africa.|Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa.
authors: Anne
authors: A
authors: von Gottberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005260:Female; D015658:HIV Infections / Q000150:complications* / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D015999:Multivariate Analysis; D011008:Pneumococcal Infections / Q000150:complications* / Q000453:epidemiology*; D022242:Pneumococcal Vaccines / Q000276:immunology / Q000627:therapeutic use*; D015995:Prevalence; D012307:Risk Factors; D065288:Serogroup; D013019:South Africa / Q000453:epidemiology; D013296:Streptococcus pneumoniae; D014611:Vaccination; D018074:Vaccines, Conjugate / Q000276:immunology / Q000627:therapeutic use; D055815:Young Adult
chemical_list: D022242:Pneumococcal Vaccines; D018074:Vaccines, Conjugate