Acquisition of Streptococcus pneumoniae and nonspecific morbidity in infants and their families: a cohort study.
BACKGROUND
Most children are believed to acquire Streptococcus pneumoniae asymptomatically, with only a few developing overt S. pneumoniae disease. This study investigates the relationship between acquisition of S. pneumoniae and mild nonspecific infection leading to general practitioner (GP) consultation.


METHODS
A prospective birth cohort study of 213 infants assessed at home 9 times during 24 weeks by nasopharyngeal swab and parental interview was conducted.


RESULTS
All positive S. pneumoniae swabs (including acquisition and carriage) were significantly associated with GP consultations for infection by the study infant compared with infants with negative swabs [odds ratio (OR), 1.6; 95% confidence interval (CI) 1.1-2.2; P = 0.005]. There was a stronger association with S. pneumoniae acquisition alone (OR 2.1; 95% CI 1.3-3.4; P = 0.001) than with carriage only (OR 1.4; 95% CI 0.9-2.0; P = 0.1). Multivariate analysis confirmed that S. pneumoniae acquisition by the study subject was independently associated with GP consultations: adjusted hazard ratio, 1.8 (95% CI 1.1-2.9); P = 0.02. A similar and independent association was found between S. pneumoniae acquisition by the study subject, and GP consultations for infection by the family (adjusted hazard ratio, 1.8; 95% CI 1.1-2.8; P = 0.01).


CONCLUSIONS
Acquisition of S. pneumoniae by the study infant was significantly associated with GP consultations for infection by the infant or family.
Sleeman
Karen L
KL
University Department of Paediatrics, John Radcliffe Hospital, University of Oxford, Oxford, United Kingdom.
Daniels
Lesley
L
Gardiner
Marion
M
Griffiths
David
D
Deeks
Jonathan J
JJ
Dagan
Ron
R
Gupta
Sunetra
S
Moxon
E Richard
ER
Peto
Tim E
TE
Crook
Derrick W
DW
D002353:Carrier State / Q000453:epidemiology*; D005260:Female; D006296:Health Services / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011008:Pneumococcal Infections / Q000453:epidemiology / Q000635:transmission*; D011446:Prospective Studies; D012307:Risk Factors; D013296:Streptococcus pneumoniae / Q000302:isolation & purification