Paul Badoux, Netherlands
Regional Laboratory of Public Health Medical MicrobiologyAuthor Of 1 Presentation
DYNAMICS OF BACTERIAL CARRIAGE DURING 12 YEARS POST PNEUMOCOCCAL CONJUGATE VACCINE (PCV) INTRODUCTION IN THE NETHERLANDS (ID 871)
Abstract
Background
Control of pneumococcal carriage is key to prevention of pneumococcal disease. We assessed the impact of PCV on carriage prevalence of Streptococcus pneumoniae(Sp) serotypes but also of Haemophilus influenzae(Hi), Staphylococcus aureus(Sa), Moraxella catarrhalis(Mc) and Group A Streptococcus(GAS).
Methods
Cross sectional observational study on carriage prevalence, determined by culture of nasopharyngeal swabs, in 24-month-old children performed in 2018/2019. Data were compared to studies performed in 2009, 2010, 2012 and 2015.
Results
Since PCV7 introduction in 2006 and change to PHiD-CV10 in 2011, overall carriage prevalence has decreased for Sp (66 to 49%) but increased for Hi (52 to 73%), Mc (59 to 83%), Sa (5.6 to 10%) and GAS (2.2 to 6.1%). Pneumococcal PHiD-CV10-type serotypes have disappeared. Initially carriage rate of NVT serotypes 19A, 11A, 10A and 23A increased but has declined again; 6C, 15A, 15B and 23B prevalence is still increasing. In 2018, 6C, 19A, 23B and 15B were the predominant serotypes in carriage and invasive disease in children <5 years of age.
Conclusions
Twelve years post-PCV introduction the decline in pneumococcal carriage has stabilized, but changes in frequency and nature of carried NVT Sp, Hi, Sa, Mc and GAS continued and should be considered for invasive and respiratory infection predictions.