We describe factors associated with pneumococcal nasopharyngeal carriage in Fiji, using data from annual (2012-2015) cross-sectional surveys, pre- and post-introduction of ten-valent pneumococcal conjugate vaccine (PCV10).
Infants (5-8 weeks), toddlers (12-23 months), children (2-6 years), and their caregivers participated. Pneumococci were detected using lytA qPCR, with molecular serotyping by microarray. We used logistic regression to determine predictors of pneumococcal carriage.
There were 8,109 participants. Pneumococcal carriage was associated with: years post-PCV10 introduction (global P<0.001), indigenous iTaukei ethnicity (aOR 2.74 [95% CI 2.17-3.45] P<0.001); young age (global P<0.001); urban residence (aOR 1.45 [95% CI 1.30-2.57] P<0.001); living with >2 children <5 years (aOR 1.42 [95% CI 1.27-1.59] P<0.001); poverty (aOR 1.44 [95% CI 1.28-1.62] P<0.001); and upper respiratory tract infection symptoms (aOR 1.77 [95% CI 1.57-2.01] P<0.001). Factors associated with PCV10 and non-PCV10 carriage were similar to those associated with overall carriage. Additionally, PCV10 carriage was associated with PCV10 vaccination (0.58 [95% CI 0.41-0.82] P=0.002) and cigarette smoke exposure (aOR 1.21 [95% CI 1.02-1.43] P=0.031, while non-PCV10 carriage was not associated with years post-PCV10 introduction.
Introduction of PCV10 reduced the odds of overall and PCV10 pneumococcal carriage in Fiji. Indigenous iTaukei ethnicity was positively associated with carriage after adjustment for PCV10.