Factors associated with pneumococcal carriage and density in children and adults in Fiji, using four cross-sectional surveys

PLoS One. 2020 Apr 1;15(4):e0231041. doi: 10.1371/journal.pone.0231041. eCollection 2020.


This study describes predictors of pneumococcal nasopharyngeal carriage and density in Fiji. We used data from four annual (2012-2015) cross-sectional surveys, pre- and post-introduction of ten-valent pneumococcal conjugate vaccine (PCV10) in October 2012. Infants (5-8 weeks), toddlers (12-23 months), children (2-6 years), and their caregivers participated. Pneumococci were detected and quantified using lytA qPCR, with molecular serotyping by microarray. Logistic and quantile regression were used to determine predictors of pneumococcal carriage and density, respectively. There were 8,109 participants. Pneumococcal carriage was negatively associated with years post-PCV10 introduction (global P<0.001), and positively associated with indigenous iTaukei ethnicity (aOR 2.74 [95% CI 2.17-3.45] P<0.001); young age (infant, toddler, and child compared with caregiver participant groups) (global P<0.001); urban residence (aOR 1.45 [95% CI 1.30-2.57] P<0.001); living with ≥2 children <5 years of age (aOR 1.42 [95% CI 1.27-1.59] P<0.001); low family income (aOR 1.44 [95% CI 1.28-1.62] P<0.001); and upper respiratory tract infection (URTI) symptoms (aOR 1.77 [95% CI 1.57-2.01] P<0.001). Predictors were similar for PCV10 and non-PCV10 carriage, except PCV10 carriage was negatively associated with PCV10 vaccination (0.58 [95% CI 0.41-0.82] P = 0.002) and positively associated with exposure to household cigarette smoke (aOR 1.21 [95% CI 1.02-1.43] P = 0.031), while there was no association between years post-PCV10 introduction and non-PCV10 carriage. Pneumococcal density was positively associated with URTI symptoms (adjusted median difference 0.28 [95% CI 0.16, 0.40] P<0.001) and toddler and child, compared with caregiver, participant groups (global P = 0.008). Predictors were similar for PCV10 and non-PCV10 density, except infant, toddler, and child participant groups were not associated with PCV10 density. PCV10 introduction was associated with reduced the odds of overall and PCV10 pneumococcal carriage in Fiji. However, after adjustment iTaukei ethnicity was positively associated with pneumococcal carriage compared with Fijians of Indian Descent, despite similar PCV10 coverage rates.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Age Factors
  • Carrier State / epidemiology*
  • Carrier State / microbiology
  • Child
  • Child, Preschool
  • Cross-Sectional Studies
  • Female
  • Fiji / epidemiology
  • Humans
  • Infant
  • Logistic Models
  • Male
  • Pneumococcal Infections / epidemiology*
  • Pneumococcal Infections / etiology
  • Pneumococcal Infections / microbiology
  • Pneumococcal Infections / prevention & control
  • Pneumococcal Vaccines / therapeutic use
  • Risk Factors
  • Young Adult


  • Pneumococcal Vaccines

Grants and funding

This project was funded by the Bill & Melinda Gates Foundation (grant numbers OPP1126272 and OPP1084341), and the Department of Foreign Affairs and Trade of the Australian Government, the Fiji Health Sector Support Program (implemented by Abt JTA on behalf of the Australian Government), with support from the Victorian Government’s Operational Infrastructure Support Program (https://www2.health.vic.gov.au/about/clinical-trials-and-research/operational-infrastructure-support). FMR was supported by a NHMRC Early Career and TRIP Fellowships (https://www.nhmrc.gov.au/). CS was supported by a NHMRC Career Development Fellowship (1087957) and a veski Inspiring Women Fellowship (https://www.veski.org.au/). EFGN holds an Australian Government Research Training Scholarship (https://www.education.gov.au/research-training-program). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.