Imperial College London
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DrLilithWhittles

Faculty of Medicine, School of Public Health

Lecturer
 
 
 
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Contact

 

l.whittles

 
 
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Location

 

School of Public HealthWhite City Campus

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Summary

 

Publications

Citation

BibTex format

@article{Lewnard:2020:cid/ciaa044,
author = {Lewnard, JA and Whittles, LK and Rick, A-M and Martin, JM},
doi = {cid/ciaa044},
journal = {Clinical Infectious Diseases},
pages = {e244--e254},
title = {Naturally-acquired protection against upper respiratory symptoms involving group A Streptococcus in a longitudinal cohort study},
url = {http://dx.doi.org/10.1093/cid/ciaa044},
volume = {71},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - BackgroundPharyngitis due to group A Streptococcus (GAS) represents a major cause of outpatient visits and antibiotic use in the United States. A leading vaccine candidate targets 30 of the >200 emm types of GAS. We aimed to assess natural protection conferred by GAS against respiratory symptoms.MethodsIn a 5-year study among school-aged children in Pittsburgh, Pennsylvania, pharyngeal cultures were obtained from children at 2-week intervals, and active surveillance was conducted for respiratory illnesses. We assessed protection via the relative odds of previous detection of homologous strains (defined by field-inversion gel electrophoresis banding pattern), emm types, and emm clusters at visits where GAS was detected with symptoms, versus visits where GAS was detected without symptoms. We used a cluster bootstrap of children to adjust estimates for repeated sampling.ResultsAt visits where previously-detected GAS emm types were identified, we estimated 81.8% (95%CI: 67.1-91.7%) protection against typical pharyngitis symptoms among children re-acquiring the same strain, and 94.5% (83.5-98.6%) protection among children acquiring a distinct strain. We estimated 77.1% (33.7-96.3%) protection against typical symptoms among children acquiring partially-heterologous emm types belonging to a previously-detected emm cluster. Protection was evident after both symptomatic and asymptomatic detections of GAS. We did not identify strong evidence of protection against atypical respiratory symptoms.ConclusionsWithin a 5-year longitudinal study, previous detection of GAS emm types was associated with protection against typical symptoms when homologous strains were subsequently detected. Naturally-acquired protection against partially-heterologous types suggests emm type-based vaccines may have broader strain coverage than what has been previously assumed.
AU  - Lewnard,JA
AU  - Whittles,LK
AU  - Rick,A-M
AU  - Martin,JM
DO  - cid/ciaa044
EP  - 254
PY  - 2020///
SN  - 1058-4838
SP  - 244
TI  - Naturally-acquired protection against upper respiratory symptoms involving group A Streptococcus in a longitudinal cohort study
T2  - Clinical Infectious Diseases
UR  - http://dx.doi.org/10.1093/cid/ciaa044
UR  - https://academic.oup.com/cid/advance-article/doi/10.1093/cid/ciaa044/5709630
UR  - http://hdl.handle.net/10044/1/76227
VL  - 71
ER  -
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