Genomic surveillance of severe acute respiratory syndrome coronavirus 2 in Burundi, from May 2021 to January 2022.

BACKGROUND: The emergence and rapid spread of new severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) variants have challenged the control of the COVID-19 pandemic globally. Burundi was not spared by that pandemic, but the genetic diversity, evolution, and epidemiology of those variants in the country remained poorly understood. The present study sought to investigate the role of different SARS-COV-2 variants in the successive COVID-19 waves experienced in Burundi and the impact of their evolution on the course of that pandemic. We conducted a cross-sectional descriptive study using positive SARS-COV-2 samples for genomic sequencing. Subsequently, we performed statistical and bioinformatics analyses of the genome sequences in light of available metadata. RESULTS: In total, we documented 27 PANGO lineages of which BA.1, B.1.617.2, AY.46, AY.122, and BA.1.1, all VOCs, accounted for 83.15% of all the genomes isolated in Burundi from May 2021 to January 2022. Delta (B.1.617.2) and its descendants predominated the peak observed in July-October 2021. It replaced the previously predominant B.1.351 lineage. It was itself subsequently replaced by Omicron (B.1.1.529, BA.1, and BA.1.1). Furthermore, we identified amino acid mutations including E484K, D614G, and L452R known to increase infectivity and immune escape in the spike proteins of Delta and Omicron variants isolated in Burundi. The SARS-COV-2 genomes from imported and community-detected cases were genetically closely related. CONCLUSION: The global emergence of SARS-COV-2 VOCs and their subsequent introductions in Burundi was accompanied by new peaks (waves) of COVID-19. The relaxation of travel restrictions and the mutations occurring in the virus genome played an important role in the introduction and the spread of new SARS-COV-2 variants in the country. It is of utmost importance to strengthen the genomic surveillance of SARS-COV-2, enhance the protection by increasing the SARS-COV-2 vaccine coverage, and adjust the public health and social measures ahead of the emergence or introduction of new SARS-COV-2 VOCs in the country.

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.

BACKGROUND: 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. METHOD: 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. RESULTS: 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). CONCLUSION: 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.

[Epidemiological profile of pertussis in infants in Casablanca from 2012 to 2019]. / Profil épidémiologique de la coqueluche du nourrisson à Casablanca de 2012 à 2019.

Pertussis is a real public health problem due to high neonatal morbidity rates and resurgence despite high vaccination coverage. The purpose of this study is to analyze the epidemiological profile of pertussis in infants hospitalized from 2012 to 2019. We conducted a retrospective, descriptive study over a 7-year and 8-month period from January 2012 to July 2019. It involved 500 infants admitted with clinical suspicion of pertussis. The average age of infants was 72 days, ranging from 28 days to 18 months; 75% of infants were less than 3 months old. The peak incidence was registered in 2012 and 2016, with a summer predominance (32%); 460 infants (92%) were not or incompletely vaccinated, 42.2% of whom were too young to be vaccinated. A probable contaminant in the entourage was found in 43,6% of cases. Whooping cough and cyanosis were the main reason for hospitalization (77.6%). Chest radiography objectified bronchial disease (25,4%) and alveolar foci (22.7%). Blood count performed in 410 infants showed hyperlymphocytosis in 67.5% of cases. Polymerase chain reaction (PCR) on nasopharyngeal sample collected from 206 infants was positive for Bordetella pertussis in 64% of cases; 118 PCR performed in mothers were positive in 47.7% of cases. All infants received Clarithromycin. Pertussis is a major cause of morbidity in infants in Casablanca. The prevention strategy is based on vaccination of family members of infants. However, vaccination of pregnant women appears to be more effective.

Alternatives Therapeutic Approaches to Conventional Antibiotics: Advantages, Limitations and Potential Application in Medicine.

Resistance to antimicrobials and particularly multidrug resistance is one of the greatest challenges in the health system nowadays. The continual increase in the rates of antimicrobial resistance worldwide boosted by the ongoing COVID-19 pandemic poses a major public health threat. Different approaches have been employed to minimize the effect of resistance and control this threat, but the question still lingers as to their safety and efficiency. In this context, new anti-infectious approaches against multidrug resistance are being examined. Use of new antibiotics and their combination with new ß-lactamase inhibitors, phage therapy, antimicrobial peptides, nanoparticles, and antisense antimicrobial therapeutics are considered as one such promising approach for overcoming bacterial resistance. In this review, we provide insights into these emerging alternative therapies that are currently being evaluated and which may be developed in the future to break the progression of antimicrobial resistance. We focus on their advantages and limitations and potential application in medicine. We further highlight the importance of the combination therapy approach, wherein two or more therapies are used in combination in order to more effectively combat infectious disease and increasing access to quality healthcare. These advances could give an alternate solution to overcome antimicrobial drug resistance. We eventually hope to provide useful information for clinicians who are seeking solutions to the problems caused by antimicrobial resistance.

Emergence of a multidrug-resistant and virulent Streptococcus pneumoniae lineage mediates serotype replacement after PCV13: an international whole-genome sequencing study.

BACKGROUND: Serotype 24F is one of the emerging pneumococcal serotypes after the introduction of pneumococcal conjugate vaccine (PCV). We aimed to identify lineages driving the increase of serotype 24F in France and place these findings into a global context. METHODS: Whole-genome sequencing was performed on a collection of serotype 24F pneumococci from asymptomatic colonisation (n=229) and invasive disease (n=190) isolates among individuals younger than 18 years in France, from 2003 to 2018. To provide a global context, we included an additional collection of 24F isolates in the Global Pneumococcal Sequencing (GPS) project database for analysis. A Global Pneumococcal Sequence Cluster (GPSC) and a clonal complex (CC) were assigned to each genome. Phylogenetic, evolutionary, and spatiotemporal analysis were conducted using the same 24F collection and supplemented with a global collection of genomes belonging to the lineage of interest from the GPS project database (n=25 590). FINDINGS: Serotype 24F was identified in numerous countries mainly due to the clonal spread of three lineages: GPSC10 (CC230), GPSC16 (CC156), and GPSC206 (CC7701). GPSC10 was the only multidrug-resistant lineage. GPSC10 drove the increase in 24F in France and had high invasive disease potential. The international dataset of GPSC10 (n=888) revealed that this lineage expressed 16 other serotypes, with only six included in 13-valent PCV (PCV13). All serotype 24F isolates were clustered in a single clade within the GPSC10 phylogeny and long-range transmissions were detected from Europe to other continents. Spatiotemporal analysis showed GPSC10-24F took 3-5 years to spread across France and a rapid change of serotype composition from PCV13 serotype 19A to 24F during the introduction of PCV13 was observed in neighbouring country Spain. INTERPRETATION: Our work reveals that GPSC10 alone is a challenge for serotype-based vaccine strategy. More systematic investigation to identify lineages like GPSC10 will better inform and improve next-generation preventive strategies against pneumococcal diseases. FUNDING: Bill & Melinda Gates Foundation, Wellcome Sanger Institute, and the US Centers for Disease Control and Prevention.

Burden of invasive pneumococcal disease in children in Casablanca, Morocco four years after the introduction of pneumococcal vaccination.

Streptococcus pneumonia is a common bacterium that can cause several types of infections, including invasive infections especially in children aged <5 years. The aim of this work is to report the different aspects of invasive pneumococcal disease (IPD) in a pediatric hospital in Casablanca, Morocco 4 years after the implementation of pneumococcal vaccination. We conducted a descriptive, retrospective study over a 4-year period from January 2015 to December 2018 in A. Harouchi Pediatric Hospital in Casablanca. This study included hospitalized children aged 0 to 14 years´ old who had an IPD. The data was collected using a data collection sheet from archived patient records and computerized laboratory database; organization of data was done using Microsoft Excel 2016 and analysis was done using SPSS-20. A total of 68 patients were included in this series over the 4-year period. Meningitis was the most common IPD (54.41%) followed by bacteremia (19.17%) and then pneumonia (16.17%). Of the 35 serogrouped strains, 7 were included in the pneumococcal conjugate vaccine (PCV) 10 (20%), 6 were PCV13-nonPCV10 serotypes (17.14%) and 6 were non-vaccine serotypes (17.14%). Among the strains tested for their antibiotic resistance profile, 32.70% were resistant to penicillin, tetracycline (29.78%), erythromycin (20.75%) and cotrimoxazole (17.31%). One strain was intermediate to ceftriaxone. The evolution was unfavorable for 18 patients (26.47%). This study reported high resistance rates to penicillin, tetracyclin and erythromycin. The mortality essentially concerned meningitis patients. Ongoing surveillance of antibiotic susceptibility and serotype distribution is needed by a national surveillance network.

Antibiotic Resistance Pattern of Extended Spectrum Beta Lactamase Producing Escherichia coli Isolated From Patients With Urinary Tract Infection in Morocco.

Extended-spectrum ß-lactamases producing Escherichia coli (ESBL-EC) lend resistance to most ß-lactam antibiotics. Because of limited treatment options, ESBL-EC infections are generally more difficult to treat, leading to higher hospital costs, reduced rates of microbiological and clinical responses, and a threat to the patient's life. This study aimed to determine the antibiotic resistance pattern of ESBL-EC isolated from patients with urinary tract infection in Morocco. This retrospective laboratory-based study was conducted at Cheikh Khalifa International University Hospital, Casablanca, from January 2016 to June 2019. A total of 670 urine samples were collected from urinary tract infection patients and processed by standard microbiological methods. In vitro susceptibility testing to different antibiotics of all identified isolates of Escherichia coli (E. coli) was performed following Kirby-Bauer's disc diffusion method on Mueller-Hinton Agar according to the EUCAST standards. The reviewing of ESBL-EC was confirmed by the appearance of a characteristically shaped zone referred to as a "champagne cork" using the Combined Disk Test. Among a total of 438 E. coli isolated from nonrepetitive urine samples, two hundred fifty-nine (59%) were ESBL-EC, of which 200 (77%) were isolated from adult patients (over the age of 50) and the majority were female. All ESBL-EC isolates were resistant to third-generation cephalosporin and quinolones and sensitive to carbapenem and fosfomycin. Knowledge of antimicrobial resistance patterns in ESBL-EC, the major pathogen associated with urinary tract infection, is indispensable as a guide in choosing empirical antimicrobial treatment.

Serotype Distribution of Remaining Pneumococcal Meningitis in the Mature PCV10/13 Period: Findings from the PSERENADE Project.

Pneumococcal conjugate vaccine (PCV) introduction has reduced pneumococcal meningitis incidence. The Pneumococcal Serotype Replacement and Distribution Estimation (PSERENADE) project described the serotype distribution of remaining pneumococcal meningitis in countries using PCV10/13 for least 5-7 years with primary series uptake above 70%. The distribution was estimated using a multinomial Dirichlet regression model, stratified by PCV product and age. In PCV10-using sites (N = 8; cases = 1141), PCV10 types caused 5% of cases <5 years of age and 15% among ≥5 years; the top serotypes were 19A, 6C, and 3, together causing 42% of cases <5 years and 37% ≥5 years. In PCV13-using sites (N = 32; cases = 4503), PCV13 types caused 14% in <5 and 26% in ≥5 years; 4% and 13%, respectively, were serotype 3. Among the top serotypes are five (15BC, 8, 12F, 10A, and 22F) included in higher-valency PCVs under evaluation. Other top serotypes (24F, 23B, and 23A) are not in any known investigational product. In countries with mature vaccination programs, the proportion of pneumococcal meningitis caused by vaccine-in-use serotypes is lower (≤26% across all ages) than pre-PCV (≥70% in children). Higher-valency PCVs under evaluation target over half of remaining pneumococcal meningitis cases, but questions remain regarding generalizability to the African meningitis belt where additional data are needed.

Whole genomic comparative analysis of Streptococcus pneumoniae serotype 1 isolates causing invasive and non-invasive infections among children under 5 years in Casablanca, Morocco.

BACKGROUND: Streptococcus pneumoniae serotype 1 remains a leading cause of invasive pneumococcal diseases, even in countries with PCV-10/PCV-13 vaccine implementation. The main objective of this study, which is part of the Pneumococcal African Genome project (PAGe), was to determine the phylogenetic relationships of serotype 1 isolates recovered from children patients in Casablanca (Morocco), compared to these from other African countries; and to investigate the contribution of accessory genes and recombination events to the genetic diversity of this serotype. RESULTS: The genome average size of the six-pneumococcus serotype 1 from Casablanca was 2,227,119 bp, and the average content of coding sequences was 2113, ranging from 2041 to 2161. Pangenome analysis of the 80 genomes used in this study revealed 1685 core genes and 1805 accessory genes. The phylogenetic tree based on core genes and the hierarchical bayesian clustering analysis revealed five sublineages with a phylogeographic structure by country. The Moroccan strains cluster in two different lineages, the five invasive strains clusters altogether in a divergent clade distantly related to the non-invasive strain, that cluster with all the serotype 1 genomes from Africa. CONCLUSIONS: The whole genome sequencing provides increased resolution analysis of the highly virulent serotype 1 in Casablanca, Morocco. Our results are concordant with previous works, showing that the phylogeography of S. pneumoniae serotype 1 is structured by country, and despite the small size (six isolates) of the Moroccan sample, our analysis shows the genetic cohesion of the Moroccan invasive isolates.

Early neonatal respiratory distress revealing meningitis caused by Streptococcus pneumoniae serotype 17F: a case report.

Background: Streptococcus pneumoniae (S. pneumoniae) is the first leading cause of invasive diseases such as meningitis, bacteremia and pneumoniae in children. In this case we report an early neonatal respiratory distress revealing meningitis caused by S. pneumoniae Serotype 17F through vertical transmission, in the newborn of 3 hours of live. Case description: A male late preterm newborn was born by vaginal delivery at a gestational age of 34 weeks. At 3 hours of life, he was admitted for early moderate neonatal respiratory distress in the Neonatal Medicine and Resuscitation Service. Cerebrospinal fluid culture yielded S. pneumoniae belonging to serotype 17F while the blood culture was negative. The same pneumococcal serotype was recovered from the high vaginal swab of the mother. Both isolates were found susceptible to all tested antibiotics except tetracycline and chloramphenicol to which the strain was resistant. Antibiotherapy management of the child included ceftriaxone at 150mg/kg/day for 21 days, in combination with gentamycin at 5 mg/kg/day for 5 days. ciprofloxacin was added at 40mg/kg/day in two doses for a period of three weeks as the baby presented a hydrocephalus. Conclusion: This finding shows that clinical manifestations of neonatal pneumococcal meningitis may be atypical and/or misleading.

A laboratory-based study of COVID-19 in Casablanca, Morocco.

Given the spread of coronavirus disease 2019 (COVID-19) and its impact on human health, laboratory confirmation of diagnosis is essential. This study examined the contribution of laboratory diagnosis to the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the diagnosis of COVID-19, taking into account patient risk of exposure to SARS-CoV-2, clinical symptoms and comorbidities. A cross-sectional, laboratory-based study was carried out from 1 April 2020 to 30 April 2020 at the National Reference Laboratory in Morocco using nasopharyngeal samples from patients admitted to the Cheikh Khalifa International University Hospital or other hospitals in Casablanca. A one-step reverse transcription real-time polymerase chain reaction (RT-PCR) was used to detect the presence of the SARS-CoV-2 genome. A national epidemiological investigation form was used to analyze patient exposure risk, clinical symptoms and comorbidities. A total of 793 samples from 375 patients were analyzed and 1150 RT-PCR tests were conducted; 116 patients (30.93%) were COVID-19 positive. Travel to a risk zone, contact with a confirmed COVID-19 case and contact with a person who had been in a risk zone were significantly associated with being positive for COVID-19. Fever and cough were the main symptoms; 7.76 % of positive patients were asymptomatic. This is the first laboratory-based study in Morocco for the diagnosis of COVID-19. Laboratory diagnosis of COVID-19 by RTPCR associated with knowledge of exposure risk factors and clinical symptoms and comorbidities remains essential for clinicians for early, appropriate medical management COVID-19 patients.

Genome Sequences of Six SARS-CoV-2 Strains Isolated in Morocco, Obtained Using Oxford Nanopore MinION Technology.

Here, we report the draft genome sequences of six severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains. SARS-CoV-2 is responsible for the COVID-19 pandemic, which started at the end of 2019 in Wuhan, China. The isolates were obtained from nasopharyngeal swabs from Moroccan patients with COVID-19. Mutation analysis revealed the presence of the spike D614G mutation in all six genomes, which is widely present in several genomes around the world.

Surgical wound infection caused by a multi drug resistant Streptococcus pneumoniae Serotype 19A after a total coloproctectomy with ileostomy.

Streptococcus pneumoniae (S. pneumoniae) colonizes asymptomatically the human nasopharynx. This pathogen is responsible for sinusitis, otitis media, pneumonia, bacteremia and meningitis. We report the case of a 35-year-old female patient who developed a surgical wound infection by a multi drug resistant S. pneumoniae serotype 19A after a total coloprotectomy. This first found in Morocco shows the implication of multidrug resistant S. pneumoniae in surgical wound infections.

Pertussis in infants, in their mothers and other contacts in Casablanca, Morocco.

BACKGROUND: In recent decades, there has been a marked increase in the number of reported cases of pertussis around the world, and pertussis continues to be a frequently occurring disease despite an effective childhood vaccination. This study aims to determine the role of household contacts of children diagnosed with pertussis in Casablanca Morocco. METHODS: From November 2015 to October 2017, children suspected of whooping cough that consulted Ibn Rochd University hospital at Casablanca with their household contacts were enrolled in the study. Nasopharyngeal (NP) samples of the suspected children were analyzed by culture and RT-PCR. For the household contacts, NP and blood samples were collected and analyzed by RT-PCR and specific detection of pertussis toxin antibodies by ELISA, respectively. RESULTS: During the study period, the survey was carried out on 128 infants hospitalized for pertussis suspicion and their families (N = 140). B. pertussis DNA was specifically detected in 73 (57%) samples, coexistence of B. pertussis and B. parapertussis DNA in 3 (2.3%) samples, coexistence of B. pertussis and B. holmesii DNA in 10 (7.81%) and only one (0.78%) sample was IS 481 RT-PCR positive without the possibility of determining the Bordetella species with the diagnostic tools used. Confirmations of Pertussis infection in household contacts by culture, RT- PCR and serology were 10, 46 and 39%, respectively. B. pertussis DNA was confirmed in the infants as well in their mothers in 38% of the cases. Co detection of B. pertussis and B. parapertussis DNA in 2% and co-detection of B. pertussis and B. holmesii DNA in 4%. B. holmesii DNA alone was detected in 5 NP samples of index cases and their mothers. CONCLUSIONS: The results of this study confirm that B. pertussis is still circulating in children and adults, and were likely a source of pertussis contamination in infants still not vaccinated. The use of RT-PCR specific for B. pertussis in the diagnosis of adults is less sensitive and should be associated with serologic tests to improve diagnosis of pertussis and contributes to preventing transmission of the disease in infants.

[Meningitis caused by Streptococcus pneumoniae serotype 7a in an infant vaccinated with two doses of 13-valent pneumococcal conjugate vaccine: a case study]. / Méningite à Streptococcus pneumoniae sérotype 7A chez un nourrisson immunisé par deux doses du vaccin pneumococcique conjugué 13-valent: à propos d'un cas.

Pneumococcal meningitis is a global scourge. It is a major cause of morbidity and mortality. In Morocco, 13-valent pneumococcal conjugate vaccine (PCV13) was introduced into the National Immunization Program in October 2010 according to the immunization schedule 2 + 1 and replaced by PCV10 in July 2012, according to the same schedule. Despite the use of the PCV13, which is essential in the fight against pneumococcal disease, the emergence of new non-vaccine serotypes always results in meningitis in children, causing serious sequelae. We report the case of an infant vaccinated with two doses of PCV13 with meningitis caused by Streptococcus pneumoniae serotype 7a. The peculiarity of this case study lies in pneumococcal meningitis due to Streptococcus pneumoniae serotype 7a not included in the PCV13 in an infant immunized by 2 doses of PCV13. We here insist on the need and the importance of an observatory for pneumococcal meningitis and of a wide epidemiological study in order to determine the serotypes in Morocco after the introduction of PCV13 and then of PCV10.

Analysis of amino acid motif of penicillin-binding proteins 1a, 2b, and 2x in invasive Streptococcus pneumoniae nonsusceptible to penicillin isolated from pediatric patients in Casablanca, Morocco.

OBJECTIVES: This study aimed to investigate the nature of the amino acid motifs found in PBPs of Streptococcus pneumoniae isolates in invasive diseases from pediatric patients at Casablanca, Morocco. Five penicillin-susceptible (PSSP), ten penicillin-intermediate (PISP), and fifteen penicillin-resistant S. pneumoniae (PRSP) were studied by PCR-RFLP and DNA sequencing of the pbp1a, - 2b, and - 2x genes. RESULTS: There were no changes in the conserved motifs of PBP1a, PBP2b and PBP2x for PSSP strains. Substitution close to PBP1a conserved motifs were found in all PRSP isolates and six/five PISP. Analysis of PBP2b showed that all but one of the 10 PISP strains and all PRSP had substitutions. Substitution close to PBP2x motifs showed that all but three of the 10 PISP strains and all PRSP had substitutions in tow conserved motifs. A total of 6, 11 and 10 genotypes were found after analysis of pbp1a, pbp2b, and pbp2x, respectively. The penicillin-nonsusceptible S. pneumoniae isolated in Casablanca share most amino acid substitutions of those reported worldwide, but they occurred among pneumococci with low level resistance to b-lactams.

[Healthcare-associated bacteraemia in intensive care units of Ibn Rochd University Hospital, Casablanca]. / Les bactériémies associées aux soins en réanimation au Centre hospitalier universitaire Ibn Rochd, Casablanca, Maroc.

Objective: This study was designed to determine the incidence of healthcare-associated bacteraemia in intensive care units (ICU) of Ibn Rochd University Hospital, Casablanca, Morocco, the frequency of the bacterial strains isolated and their antibiotic resistance patterns. Methods: A prospective longitudinal study was conducted between May and July 2015 on patients admitted to the Ibn Rochd University Hospital ICU. The Comité technique des infections nosocomiales et des infections liées aux soins (CITNILS) definition of bacteraemia was used. Micro-organisms were isolated and identified according to standard bacteriology techniques. Antibiotic susceptibility testing was performed according to CLSI 2013 guidelines. Results: A total of 720 patients were hospitalised during the study period; 48 (6.7%) acquired healthcare-associated bacteraemia with an incidence ranging from 7.3/1,000 HD to 13.7/1,000 HD. Fifty-four bacteria were isolated: A. baumannii and K. pneumoniae each accounted for 18.5% of isolates. 66.7% of A. baumannii strains were resistant to imipenem and 20% of K. pneumoniae strains were ESBL+ Conclusion: Healthcare-associated bacteraemia raises treatment problems due to multidrug-resistant bacteria, which is why regular surveillance is necessary to evaluate the time-course of these strains and the efficacy of prevention measures.

Epidemiology of pertussis in Casablanca (Morocco): contribution of conventional and molecular diagnosis tools.

BACKGROUND: Pertussis, a vaccine preventable disease, is still responsible of significant morbidity and mortality around the world, mostly in newborns. The aim of the present study was (1) to introduce pertussis surveillance in the major pediatric hospital of Casablanca (2) to analyze the prevalence of pertussis among children under 14 years of age and their entourage in Casablanca, Morocco. METHODS: This is a prospective and non-case controlled study, including children suspected of Pertussis admitted at the Abderrahim Harouchi Pediatric Hospital in Casablanca, from January 2013 to June 2015. Nasopharyngeal samples were obtained for Bordetella spp. culture and Real time PCR detection (RT-PCR) with specific primers of Bordetella spp., B. pertussis, B. parapertussis and B. holmesii. The detection of Bordetella spp. was also performed in some household contacts of the children suspected of pertussis. RESULTS: During the 2.5-years period, a total of 282 samples were collected from hospitalized children (156) and in some of their contacts (126). Among 156 samples from the children (from whom 57% were under 2 month of age), Bordetella DNA was detected in 61% (96/156) by RT-PCR. Among these positive samples, 91.7% (88/96) corresponded to B. pertussis DNA. Furthermore, in 39.5% (38/96) of the Bordetella positive samples, B. holmesii DNA was also detected. B. parapertussis DNA was detected in only one sample (1/156). Out of the 156 samples collected from the hospitalized children, only 48 were tested by culture, and 4 B. pertussis were isolated (8.3%). Among the 126 samples from the contacts of the children, mostly mothers (115 cases), Bordetella DNA was detected in 47% (59/126), 90% (53/59) being B. pertussis DNA. Moreover, B. holmesii DNA was also detected in 18.6% (11/59) of the Bordetella positive samples, and coexistence of B. pertussis and B. holmesii DNA in 36.5% (35/96). Two B. pertussis were isolated by culture performed on 43 samples of the contacts of the children (4.6%). CONCLUSIONS: This study highlights the circulation of B. pertussis but also of B. holmesii in Casablanca-Morocco with a high proportion of co-infections B. holmesii/B. pertussis in infants and their mothers, indicate that infection of non-vaccinated infants could be more associated with young parents. Moreover, the RT- PCR provides a sensitive and specific diagnosis of B. pertussis infections and distinguishes it from other Bordetella species, and is therefore suitable for implementation in the diagnostic laboratory.

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

BACKGROUND: Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide, especially among children and the elderly. The ability to effectively treat pneumococcal infection has been compromised due to the acquisition of antibiotic resistance, particularly to ß-lactam drugs. This study aimed to describe the prevalence and molecular evolution of penicillin non-susceptible S. pneumoniae (PNSP) isolated from invasive diseases before and after pneumococcal conjugate vaccine implementation in Casablanca, Morocco. METHODS: Isolates were obtained from the Microbiology Laboratory of Ibn Rochd University Hospital Centre of Casablanca. Serogrouping was done by Pneumotest Kit and serotyping by the Quellung capsular swelling. Antibiotic susceptibility pattern was determined by disk diffusion and E-test methods. The PNSP were analyzed by pulsed-field gel electrophoresis (PFGE) and by genotyping of pbp1a, pbp2b, and pbp2x genes. RESULTS: A total of 361 S. pneumoniae isolates were collected from 2007 to 2014. Of these isolates, 58.7% were obtained before vaccination (2007-2010) and 41.3% after vaccination (2011-2014). Of the 361 isolates, 80 were PNSP (22.2%). Generally, the proportion of PNSP between pre- and post-vaccination periods were 31 and 13% (p = 0.009), respectively. The proportion of PNSP isolated from pediatric and adult (age > 14 years) patients decreased from 34.5 to 22.9% (p = 0.1) and from 17.7 to 10.2% (p = 0.1) before and after vaccine implementation, respectively. The leading serotypes of PNSP were 14 (33 vs. 57%) and 19A (18 vs. 14%) before and after vaccination among children. For adults, serotypes 19A (53%) and 23F (24%) were the dominant serotypes in the pre-vaccination period, while serotype 14 (22%) was the most prevalent after vaccination. There were 21 pbp genotypes in the pre-vaccination period vs. 12 for post-vaccination period. PFGE clustering showed six clusters of PNSP grouped into three clusters specific to pre-vaccination period (clusters I, II and III), two clusters specific to post-period (clusters V and VI) and a cluster (IV) that contained clones belonging to the two periods of vaccination. CONCLUSION: Our observations demonstrate a high degree of genetic diversity among PNSP. Genetic clustering among PNSP strains showed that they spread mainly by a restricted number of PNSP clones with vaccine serotypes. PFGE clustering combined with pbp genotyping revealed that vaccination can change the population structure of PNSP.

A case report of parapneumonic pleural effusion caused by Streptococcus pneumoniae serotype 19A in a child immunized with 13-valent conjugate pneumococcal vaccine.

BACKGROUND: Simple parapneumonic effusion is a pleural effusion associated with lung infection (i.e., pneumonia). Streptococcus pneumoniae remains the most common pathogen causing parapneumonic effusions. In Morocco, the pneumococcal conjugate vaccine 13-valent (PCV13) was introduced in the national immunization program in October 2010 in 2 + 1 schedule for prevention of pneumococcal disease, and replaced by the PCV10 in July 2012 in the same schedule. We report a case of parapneumonic pleural effusions caused by S. pneumoniae serotype 19A in a child immunized with 3 doses of PCV13. CASE PRESENTATION: This is a 2.5 years old previously healthy Moroccan female, fully vaccinated by PCV13 and immunocompetent, admitted to a private medical clinic with a six months history of persistent asthma. On arrival (7 February 2015), she was febrile to 40.3 °C with a brutal flu syndrome, chills, dry cough and serous rhinitis, for which she received symptomatic treatment. A biological assessment was done that confirmed the clinical diagnosis of flu. Seven days after, she presented a progressive deterioration of its general condition and the onset of severe abdominal pain. She was hospitalized and a second biological assessment, computed tomography scans and chest radiography were done that confirmed a diagnosis of a pneumococcal parapneumonia with abscess of the left lower lobe with encysted empyema. Microbiological analysis of the pleural fluid showed a S. pneumoniae serotype 19A with susceptibility intermediate to penicillin. The patient was treated by antibiotics including amoxicillin, cefixime ceftriaxone and vancomycin. CONCLUSIONS: We reported a case of parapneumonic pleural effusions caused by a vaccine serotype pneumococcal 19A occurring in an immunocompetent child immunized with 3 doses of PCV13.