Katrien Lagrou, Belgium
UZ Leuven/ KU Leuven Microbiology, Immunology and TransplantationAuthor Of 3 Presentations
INCREASE IN PCV13-ONLY SEROTYPE INVASIVE PNEUMOCOCCAL DISEASE IN CHILDREN AND OLDER PERSONS DURING PCV10 PERIOD (2015-2019) IN BELGIUM (ID 252)
IN-DEPTH ANALYSIS OF PNEUMOCOCCAL SEROTYPES IN BELGIAN CHILDREN (2015-2018): DIVERSITY AND INVASIVE DISEASE POTENTIAL OF SEROTYPES IN CARRIAGE AND DISEASE (ID 1032)
Abstract
Background
Over a three year period (2015-2018) during and immediately after the PCV13-to-PCV10-switch in Belgium, nasopharyngeal pneumococcal carriage monitoring and IPD surveillance data are used to study invasive disease potential and distribution of pneumococcal serotypes.
Methods
Strains isolated from children up to 30 months of age, either attending day-care or diagnosed with IPD were serotyped by Quellung-reaction. Invasive disease potential was defined as the serotype-specific Odds ratio (OR).
Results
Over the entire study period, different serotypes dominated in each population: 12F, 19A, 10A, 33F in IPD versus 23B, 23A, 11A, 15B in carriage, but the proportion of non-PCV13 vaccine serotypes (VT) was high in both (IPD: 83.0%; carriage: 93.6%). The highly invasive (OR>1) serotypes (12F, 1, 3, 24A/B/F, 33F, 19A, 9N) accounted for 53.2% of IPD cases and were not frequently carried (<3.5%). From 2015 to 2018, PCV13 vaccine serotypes increased (p<0.01) in carriage (from 5.4%, 25/463 to 10.3%, 69/668) and in IPD-surveillance (from 7.3%, 8/110 to 23.9%, 34/142) mainly due to an increase (p<0.01) in serotype 19A.
Conclusions
A majority of the serotypes with high invasive disease potential circulating in Belgium are not included in the currently used PCVs, reinforcing the need for continuous IPD surveillance and carriage monitoring.