Serotype distribution and antimicrobial susceptibility of invasive Streptococcus pneumoniae isolates among adult and elderly population before and after introduction of pneumococcal conjugate vaccine in Casablanca, Morocco.

Streptococcus pneumoniae (S. pneumoniae), remains a major cause of mortality and morbidity worldwide. The objective of this study was to determine the trends of invasive pneumococcal diseases (IPD) in adult and elderly population in Casablanca (Morocco) before and after introduction of pneumococcal conjugate vaccine (PCV) by determining the distribution of pneumococcal serotypes and antibiotic resistance profile of isolated strains. The proposed study is a retrospective laboratory-based surveillance of IPD in hospitalized adult (15-59 years old) and elderly (≥ 60 years old) patients in Ibn Rochd University Hospital Centre from 2007 to 2019 (13 years). All the 250 non-duplicate clinical invasive isolates from adult and elderly patients, confirmed as S. pneumoniae according to the laboratory standard identification procedures, are included in this study. A significant decrease of the overall incidence in IPD was observed only in adults from 0.71 to 0.54/100000 populations (P  =  0.02) and to 0.47/100000 populations (P  =  0.0137) in the early and mature post-vaccine period respectively compared to the pre-vaccine period. Our results also showed a significant reduction in the overall prevalence of vaccine serotypes from 28.17 to 6.90% (P  =  0.0021) for the PCV-10 serotypes, and from 46.48 to 25.86% (P  =  0.0164) for the PCV-13 serotypes only in the mature post-vaccine period (2015-2019). In parallel, the rate of non-vaccine serotypes did not significantly change in the early post-vaccine period (2011-2014) while it increased considerably from 54 to 74.14% (P  =  0.0189) during the mature post-vaccine period. The rate of penicillin non-susceptible pneumococcal isolates decreased significantly from 23.94 to 8.77% (P  =  0.02) in adult patients, and the rate of cotrimoxazole non-susceptible pneumococcal isolates significantly decreased from 29.58 to 8.77% in the early post-vaccine period (P  =  0.003) and to 7.24% in the mature post-vaccine period (P  =  0.0007). Although childhood vaccination has considerably reduced the incidence of IPD in adult population through the herd effect, IPD remain a real public health problem due to the alarming increase in non-vaccine serotypes (NVS) and the lack of herd effect among elderly population. The rate of antibiotic resistance was relatively low. Nevertheless, resistance constitutes a serious problem to the therapeutic arsenal due to the known capacity for genetic dissemination in the pneumococcus.

Nzoyikorera N ，Diawara I ，Katfy M ，Katfy K ，Maaloum F ，Nyandwi J ，Belabbes H ，Elmdaghri N ，Zerouali K ... -  《BMC INFECTIOUS DISEASES》

Molecular characterization of penicillin non-susceptible Streptococcus pneumoniae isolated before and after pneumococcal conjugate vaccine implementation in Casablanca, Morocco.

Diawara I ，Barguigua A ，Katfy K ，Nayme K ，Belabbes H ，Timinouni M ，Zerouali K ，Elmdaghri N ... -  《Annals of Clinical Microbiology and Antimicrobials》

Invasive pneumococcal disease among children younger than 5 years of age before and after introduction of pneumococcal conjugate vaccine in Casablanca, Morocco.

The purpose of this study was to compare the incidence rate of invasive pneumococcal disease, the rates of antibiotic resistance and serotype distribution among children ≤5 years old before and after PCVs introduction in Casablanca, Morocco. This study was conducted at the Ibn Rochd University Hospital Centre of Casablanca during two periods encompassing pre-and post-implementation of PCVs, respectively from January 2007 to October 2010 and from January 2011 to December 2014. All the non-duplicate invasive S. pneumoniae isolates recovered during the study periods were included. There were 136 cases of IPD, 91 before and 45 after PCVs introduction. The greatest decrease in incidence rate of IPD occurred in children ≤ 2 years of age declining from 34.6 to 13.5 per 100,000 populations (p<0.0001) before and after vaccination, respectively. The incidence rate of PCV-7, PCV-10 non-PCV-7 and PCV-13 non-PCV-10 serotypes decrease significantly from 18.0 to 4.6, from 5.7 to 1.3 and from 5.7 to 0.8/100,000 population (p<0.001) in the same age, respectively. Shifts in the distribution of IPD serotypes and reductions in the incidence rate of disease suggest an effective reduction of the burden of IPD in children, but continued high quality surveillance is critical to assess the changes in serotype distributions.

Diawara I ，Zerouali K ，Katfy K ，Zaki B ，Belabbes H ，Najib J ，Elmdaghri N ... -  《-》

CIRCULATING CLONAL COMPLEXES AND SEQUENCE TYPES OF STREPTOCOCCUS PNEUMONIAE SEROTYPE 19A WORLDWIDE: THE IMPORTANCE OF MULTIDRUG RESISTANCE: A SYSTEMATIC LITERATURE REVIEW.

Ruiz García Y ，Nieto Guevara J ，Izurieta P ，Vojtek I ，Ortega-Barría E ，Guzman-Holst A ... -  《-》

Invasive Pneumococcal Infections Among Moroccan Children: Pneumococcal Vaccination Challenges in the Mature Vaccine Era.

Zerouali K ，Katfy M ，Kettani AE ，Nzoyikorera N ，Katfy K ，Bousfiha AA ，Gueddari W ，Slaoui B ，Abkari A ，Chlilek A ，Diawara I ，Zouhair S ，Asmae LH ，Younous S ，Mouaffak Y ，Bourrous M ，Lahmini W ，Rada N ，Draiss G ，Soraa N ，Bouskraoui M ... -  《Clinical Laboratory》