Amy Tunali, United States of America
Emory University and Georgia Emerging Infections Program, Atlanta VAMC Division of Infectious DiseasesPresenter of 1 Presentation
STREPTOCOCCUS PNEUMONIAE (SP) NASOPHARYNGEAL CARRIAGE (NPC) AMONG ADOLESCENTS AGE 11-17 YEARS, ATLANTA, GA, USA 2018 (ID 1000)
Abstract
Background
Pneumococcal nasopharyngeal carriage (SP-NPC) in children aged <5 years is well-described. Less is known about SP-NPC in adolescents. SP-NPC studies in Atlanta documented carriage rates of ~30% in children aged <5 years. We evaluated SP-NPC in adolescents.
Methods
NP swabs collected from children aged 11-17 years in an Atlanta emergency department from December 2017-December 2018 were broth-enriched, cultured for SP, and serotyped. Demographics and medical and immunization records were collected.
Results
Of 260 adolescents enrolled, 8 (3.1%) had SP-NPC. Mean age of enrollees was 13.5 years (12.9 years for carriers); 58% were female (63% for carriers). 72% had no documented underlying conditions (50% for carriers). 50% of carriers reported having asthma. Among enrollees with immunization records available, 132/219 (60%) overall and 5/6 (83%) carriers were fully immunized for SP with PCV7. 2 carried vaccine serotypes (VT): S3 (PCV13 VT), S19F (PCV7/13 VT) but were immunized with PCV7 only. 6 carried non-VT: S6C, S15C, S21, S23A, S23B, S37.
Conclusions
Adolescent SP-NPC was low compared to children aged <5 years in Atlanta, GA USA, illustrating adolescents’ limited role in SP-NPC. Adolescent SP-NPC of mostly non-VT, despite lack of PCV13 immunization, supports successes of routine pediatric vaccination and herd immunity.
Author Of 2 Presentations
STREPTOCOCCUS PNEUMONIAE (SP) NASOPHARYNGEAL CARRIAGE (NPC) AMONG ADOLESCENTS AGE 11-17 YEARS, ATLANTA, GA, USA 2018 (ID 1000)
Abstract
Background
Pneumococcal nasopharyngeal carriage (SP-NPC) in children aged <5 years is well-described. Less is known about SP-NPC in adolescents. SP-NPC studies in Atlanta documented carriage rates of ~30% in children aged <5 years. We evaluated SP-NPC in adolescents.
Methods
NP swabs collected from children aged 11-17 years in an Atlanta emergency department from December 2017-December 2018 were broth-enriched, cultured for SP, and serotyped. Demographics and medical and immunization records were collected.
Results
Of 260 adolescents enrolled, 8 (3.1%) had SP-NPC. Mean age of enrollees was 13.5 years (12.9 years for carriers); 58% were female (63% for carriers). 72% had no documented underlying conditions (50% for carriers). 50% of carriers reported having asthma. Among enrollees with immunization records available, 132/219 (60%) overall and 5/6 (83%) carriers were fully immunized for SP with PCV7. 2 carried vaccine serotypes (VT): S3 (PCV13 VT), S19F (PCV7/13 VT) but were immunized with PCV7 only. 6 carried non-VT: S6C, S15C, S21, S23A, S23B, S37.
Conclusions
Adolescent SP-NPC was low compared to children aged <5 years in Atlanta, GA USA, illustrating adolescents’ limited role in SP-NPC. Adolescent SP-NPC of mostly non-VT, despite lack of PCV13 immunization, supports successes of routine pediatric vaccination and herd immunity.
DETECTION OF STREPTOCOCCUS PNEUMONIAE (SP) NASOPHARYNGEAL CARRIAGE (NPC) BY PCR ON DNA ISOLATED FROM PEDIATRIC NP SWABS PREVIOUSLY DETERMINED TO BE SP-NPC NEGATIVE BY CULTURE (ID 916)
Abstract
Background
Monitoring Streptococcus pneumoniae nasopharyngeal carriage (SP-NPC) and SP serotype distribution is critical to evaluate the impact and efficacy of pneumococcal vaccine programs. The gold standard for pneumococcal colonization and serotype distribution is culture, followed by serotyping with antisera. Detection of very low density SP colonization or concurrent colonization by multiple serotypes may be missed by culture. Real-Time PCR (RT-PCR) targeting SP genes lytA (major autolysin) and SP2020 (putative transcriptional regulator) has been identified as a powerful and sensitive molecular strategy for identification of SP.
Methods
NP swabs collected from children <5 years in an emergency department in Atlanta, GA in 2017 were broth-enriched, cultured for SP, and serotyped. RT-PCR targeting lytA and SP2020 was performed on all NP swabs negative for SP by culture. Subsequent RT-PCR targeting capsule polysaccharide-specific cpsA, associated with encapsulated SP strains, was performed on all ltyA and SP2020-positive/culture-negative NP swabs.
Results
622 children were enrolled; 182 (29.3%) had SP-NPC by culture. Of the 440 culture-negative, 59/440 (13.4%) were positive for lytA/SP2020 with 45/59 (76.2%) cspA+.
Conclusions
Molecular detection of SP from NP swabs increased carriage from 29.3% to 38.7%. 76.2% of SP identified by RT-PCR appear to be encapsulated and molecular serotyping is currently underway.