Duration of nasopharyngeal carriage of penicillin-resistant Streptococcus pneumoniae: experiences from the South Swedish Pneumococcal Intervention Project.
As a part of an intervention project, all detected carriers of penicillin-resistant pneumococci (PRP) (MIC, > or = 0.5 mg/L) in Malmöhus County, southern Sweden, were followed by means of weekly nasopharyngeal cultures. The median duration of carriage in 678 individuals was 19 days (range, 3-267 days). The duration of carriage was longest in children < 1 year old (median, 30 days) and shortest in adults > 18 years old (median, 14 days). Index cases, whose cultures were performed during an acute infection, were carriers for a mean of 10 days longer than asymptomatic contact cases (P < .05). The PRP spontaneously disappeared from the nasopharynx within 4 weeks in 68%, within 8 weeks in 87%, and within 12 weeks in 94% of the individuals. Other significant risk factors for prolonged carriage were the occurrence of > 6 episodes of acute otitis media (AOM) or first episode of AOM before the age of 1 year (P < .01), the carriage of PRP by other family members (P < .05), and the obtainment of a first positive culture during the winter months (P < .05).
Ekdahl
K
K
Center of Communicable Disease Control in Malmöhus County, Malmö, Sweden.
Ahlinder
I
I
Hansson
H B
HB
Melander
E
E
Mölstad
S
S
Söderström
M
M
Persson
K
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008875:Middle Aged; D009305:Nasopharynx / Q000382:microbiology*; D010403:Penicillin Resistance; D013296:Streptococcus pneumoniae / Q000187:drug effects* / Q000302:isolation & purification; D013548:Sweden