title: Nasopharyngeal carriage of Streptococcus pneumoniae: prevalence and risk factors in HIV-positive children in Tanzania.
abstract: BACKGROUND
  Pneumococcal colonization of the nasopharynx is especially common in young children and is a pre-requisite for pneumococcal disease. Those with immunosuppression, such as HIV, are at higher risk of colonization and disease, especially at older ages. Currently, vaccination schedules are only offered to children under 6 months of age, despite the large impact of pneumococcal disease in older unvaccinated children with HIV. We conducted a study to assess the prevalence of, and risk factors for, pneumococcal carriage in HIV-positive children aged <15 years.
  
  
  METHODS
  We collected a single nasopharyngeal swab from 142 HIV-infected children aged 1-14 years over a 2-month period. To detect carriage of pneumococcus, these samples were cultured and serotyped; PCR was performed on negative samples. We also collected epidemiological data via survey and medical records.
  
  
  RESULTS
  The overall carriage rate was 81% and was at least 76% in those aged 5-14 years. The 7-, 10-, and 13-valent pneumococcal vaccines would cover 37%, 37%, and 49% of children with carriage, respectively. In the multivariate analysis, we identified increase in weight since last visit (p=0.028) and the existence of care-givers who had respiratory symptoms in the past week (p=0.022) as risk factors for carriage. Weight gain was also significantly associated with antiretroviral use (p=0.002).
  
  
  CONCLUSIONS
  These data illuminate the little known area of pneumococcal carriage in older HIV-infected children as well as finding novel risk factors for pneumococcal carriage, namely the association with household members who have respiratory symptoms and with an increase in the child's weight prior to swabbing. Weight gain may be due to an increase in health enabling more mobility and increasing the risk of acquiring carriage. The carriage rate observed (81%) is one of the highest recorded. Further research should address whether vaccination can prevent the acquisition of carriage and so protect against disease.
authors.affiliation: Discipline of Paediatrics and Child Health, The University of Sydney, NSW, Australia.
authors.forename: Laura
authors.initials: L
authors.lastname: Anthony
authors.forename: Andrea
authors.initials: A
authors.lastname: Meehan
authors.forename: Ben
authors.initials: B
authors.lastname: Amos
authors.forename: George
authors.initials: G
authors.lastname: Mtove
authors.forename: Julius
authors.initials: J
authors.lastname: Mjema
authors.forename: Rajabu
authors.initials: R
authors.lastname: Malahiyo
authors.forename: Jiehui Kevin
authors.initials: JK
authors.lastname: Yin
authors.forename: Shahin
authors.initials: S
authors.lastname: Oftadeh
authors.forename: Gwendolyn L
authors.initials: GL
authors.lastname: Gilbert
authors.forename: Delane
authors.initials: D
authors.lastname: Shingadia
authors.forename: Hugh
authors.initials: H
authors.lastname: Reyburn
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Deen
authors.forename: Peter C
authors.initials: PC
authors.lastname: Richmond
authors.forename: Robert
authors.initials: R
authors.lastname: Booy
mesh_terms: D000293:Adolescent; D002353:Carrier State / Q000453:epidemiology* / Q000382:microbiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006679:HIV Seropositivity / Q000150:complications* / Q000453:epidemiology; D006801:Humans; D007223:Infant; D008297:Male; D009305:Nasopharynx / Q000382:microbiology; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000276:immunology / Q000382:microbiology; D022242:Pneumococcal Vaccines / Q000008:administration & dosage / Q000276:immunology; D015995:Prevalence; D012307:Risk Factors; D012703:Serotyping; D013296:Streptococcus pneumoniae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D013636:Tanzania / Q000453:epidemiology
chemical_list: D022242:Pneumococcal Vaccines