Nasopharyngeal carriage of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Alloiococcus otitidis in young children in the era of pneumococcal immunization, Taiwan

Molecular Infectious Diseases Research Center, Chang Gung Memorial Hospital, Taiwan.
Scandinavian Journal of Infectious Diseases (Impact Factor: 1.5). 09/2011; 43(11-12):937-42. DOI: 10.3109/00365548.2011.601754
Source: PubMed


We applied a multiplex polymerase chain reaction (PCR) and culture to detect Streptococcus pneumoniae and detected 3 other respiratory pathogens--Haemophilus influenzae, Moraxella catarrhalis, and Alloiococcus otitidis--simultaneously by PCR, in the nasopharynx of 386 children aged under 5 y. S. pneumoniae was the most common pathogen carried by children in all age groups, with the rate ranging from 15.8% in children aged 3-4 y to 28.6% in children aged 2-3 y. H. influenzae and M. catarrhalis showed similar carriage rates across all the age groups. Only 2 young children (0.5%) carried A. otitidis. Higher carriage of S. pneumoniae was found in children who had not received the heptavalent pneumococcal conjugate vaccine (PCV7). Cefotaxime non-susceptibility was high (51.4%) in S. pneumoniae nasopharyngeal isolates. Serotype 6B was the most common in fully immunized carriers and also in those who received catch-up immunization. Due to low PCV7 coverage in Taiwan, the carriage of vaccine and non-vaccine serotypes of S. pneumoniae in children remains common.

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