Descriptive epidemiology of nasal carriage of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus among patients admitted to two healthcare facilities in Algeria

Genetic Diversity and Virulence Profile of Methicillin and Inducible Clindamycin-Resistant Staphylococcus aureus Isolates in Western Algeria

Staphylococcusaureus causes a wide range of life-threatening infections. In this study, we determined its prevalence in the hospital environment and investigated nasal carriage among healthcare workers and patients admitted to a hospital in western Algeria. A total of 550 specimens were collected. An antibiogram was performed and the genes encoding resistance to methicillin, inducible clindamycin and toxins were sought among the 92 S. aureus isolates. The spread of clones with a methicillin- and/or clindamycin-resistance phenotype between these ecosystems was studied using genomic analysis. A prevalence of 27%, 30% and 13% of S. aureus (including 2.7%, 5% and 1.25% of MRSA) in patients, healthcare workers and the hospital environment were observed, respectively. The presence of the mecA, erm, pvl and tsst-1 genes was detected in 10.9%, 17.4%, 7.6% and 18.5% of samples, respectively. Sequencing allowed us to identify seven sequence types, including three MRSA-IV-ST6, two MRSA-IV-ST80-PVL+, two MRSA-IV-ST22-TSST-1, two MRSA-V-ST5, and one MRSA-IV-ST398, as well as many virulence genes. Here, we reported that both the hospital environment and nasal carriage may be reservoirs contributing to the spread of the same pathogenic clone persisting over time. The circulation of different pathogenic clones of MRSA, MSSA, and iMLSB, as well as the emergence of at-risk ST398 clones should be monitored.

A 6-Year Update on the Diversity of Methicillin-Resistant Staphylococcus aureus Clones in Africa: A Systematic Review

Background

Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of hospital-associated (HA) and community-associated (CA) infections globally. The multi-drug resistant nature of this pathogen and its capacity to cause outbreaks in hospital and community settings highlight the need for effective interventions, including its surveillance for prevention and control. This study provides an update on the clonal distribution of MRSA in Africa.

Methods

A systematic review was conducted by screening for eligible English, French, and Arabic articles from November 2014 to December 2020, using six electronic databases (PubMed, EBSCOhost, Web of Science, Scopus, African Journals Online, and Google Scholar). Data were retrieved and analyzed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines (registered at PROSPERO: CRD42021277238). Genotyping data was based primarily on multilocus sequence types (STs) and Staphylococcal Cassette Chromosome mec (SCCmec) types. We utilized the Phyloviz algorithm in the cluster analysis and categorization of the MRSA STs into various clonal complexes (CCs).

Results

We identified 65 studies and 26 publications from 16 of 54 (30%) African countries that provided sufficient genotyping data. MRSA with diverse staphylococcal protein A (spa) and SCCmec types in CC5 and CC8 were reported across the continent. The ST5-IV [2B] and ST8-IV [2B] were dominant clones in Angola and the Democratic Republic of Congo (DRC), respectively. Also, ST88-IV [2B] was widely distributed across the continent, particularly in three Portuguese-speaking countries (Angola, Cape Verde, and São Tomé and Príncipe). The ST80-IV [2B] was described in Algeria and Egypt, while the HA-ST239/ST241-III [3A] was only identified in Egypt, Ghana, Kenya, and South Africa. ST152-MRSA was documented in the DRC, Kenya, Nigeria, and South Africa. Panton-Valentine leukocidin (PVL)-positive MRSA was observed in several CCs across the continent. The median prevalence of PVL-positive MRSA was 33% (ranged from 0 to 77%; n = 15).

Conclusion

We observed an increase in the distribution of ST1, ST22, and ST152, but a decline of ST239/241 in Africa. Data on MRSA clones in Africa is still limited. There is a need to strengthen genomic surveillance capacity based on a "One-Health" strategy to prevent and control MRSA in Africa.

Emergence of Methicillin-Resistant Staphylococcus aureus ST239/241 SCCmec-III Mercury in Eastern Algeria

In this paper, we investigate the epidemiology of infections-associated Staphylococcusaureus (S. aureus) from the Medical Intensive Care Unit (MICU) at University Hospital Center of Constantine (UHCC) in Algeria, with a special emphasis on methicillin-resistant strains (MRSA) revealed by cefoxitin disks (30 μg), then confirmed by penicillin-binding protein (PBP2a) agglutination and real-time polymerase chain reaction (RT-PCR) targeting mecA and mecC genes. Staphylococcal Cassette Chromosome mec (SCCmec type), staphylococcal protein A (spa-type), multilocus sequence type (MLST), Panton-Valentine Leucocidin (PVL), and toxic shock syndrome toxin-1 (TSST-1) were further investigated in all isolates, and whole genome sequencing was performed for a selected subset of three hospital-acquired MRSA (HA-MRSA) isolates. A measurement of 80% out of the 50 S. aureus isolates were identified as HA-MRSA harbouring the mecA gene, and 72.5% of them were multidrug resistant (MDR). Twelve STs, four different SCCmec cassettes, fourteen spa types, ten isolates Panton-Valentine Leukocidin (PVL)-positive, and three isolates TSST-1 were identified. Interestingly, there was a high prevalence (n = 29; 72.5%) of a worrisome emerging clone: the HA-MRSA ST239/241 SCCmec-III mercury with PVL negative, resistant to β-lactams, aminoglycosides, quinolones, and tetracyclines. Other clones of HA-MRSA isolates were also identified, including PVL-positive ST80 SCCmec-IV/SCCmec-unknown (22.5%), ST34 SCCmec-V with TSST-1 positive (2.5%), and PVL-negative ST72 SCCmec-II (2.5%). Genome analysis enables us to describe the first detection of both PVL-negative HA-MRSA ST239/241 SCCmec-III mercury carrying ccrC, as well as SCCmec-V cassette, which dramatically changes the epidemiology of S. aureus infections in one of the hospitals in eastern Algeria.

Epidemiology of Methicillin-Resistant Staphylococcus Aureus in Arab Countries of the Middle East and North African (MENA) Region

Available data suggest a high burden of methicillin-resistant staphylococcus aureus (MRSA) in Arab countries of the Middle East and North Africa (MENA). To review the MRSA rates and molecular epidemiology in this region, we used PubMed search engine to identify relative articles published from January 2005 to December 2019. Great heterogeneity in reported rates was expectedly seen. Nasal MRSA colonization ranged from 2%–16% in Gulf Cooperation Council (GCC), 1–9% in the Levant, and 0.2%–9% in North African Arab states. Infective MRSA rates ranged from 9%–38% in GCC, 28%–67% in the Levant, and 28%–57% in North African states. Studies demonstrated a wide clonal diversity in the MENA. The most common molecular types belonged to 5 clonal complexes (CC) known to spread worldwide: CC5, CC8, CC22, CC30, and CC80. The most prevalent strains had genotypes related to the European community-acquired MRSA (CA-MRSA), Brazilian/Hungarian hospital-acquired MRSA (HA-MRSA), UK-EMRSA-15 HA-MRSA, and USA300 CA-MRSA. Finally, significant antimicrobial resistance was seen in the region with variation in patterns depending on location and clonal type. For a more accurate assessment of MRSA epidemiology and burden, the Arab countries need to implement national surveillance systems.

Methicillin-Resistant Staphylococcus Aureus (MRSA) in Poultry Species in Algeria: Long-Term Study on Prevalence and Antimicrobial Resistance

Methicillin-resistant Staphylococcus aureus (MRSA) is a well-known pathogen with a serious impact on human and veterinary public health. To determine antibiotic resistance of MRSA in poultry, 4248 nasal swabs were collected from 840 poultry farms in 18 different Wilayas (provinces) of Algeria. Swabs were collected between 2011 and 2018 from breeding hens, laying hens, broilers, and turkeys. Identification was carried out by the classical culture methods, and the disc diffusion test was used to determine the antibiotic resistance patterns. S. aureus was isolated from 477 (56.8%) farms, and flock prevalence was 52.8%, 48.8%, 48.4%, and 75.6% in breeding hens, laying hens, broilers, and turkeys, respectively. MRSA was isolated from 252 (30%) farms and flock prevalence was 22%, 33.5%, 27.4%, and 36%, respectively. As expected, all MRSA isolates were resistant to cefoxitin, penicillin G, amoxicillin/clavulanic acid, and oxacillin. High levels of resistance were found for tetracycline (82.5%), erythromycin (70.6%), clindamycin (68.6%), and ciprofloxacin (50%). Almost all isolates were susceptible to vancomycin (100%) and mupirocin and rifampicin (99.2%), followed by chloramphenicol (82.3%), and gentamicin (76%). This moderate proportion of MRSA in poultry poses a considerable risk to public health. The results of this study highlight the need for control programs that encompass primary animal production and the food chain to mitigate contamination and spread of MRSA in the poultry industry of Algeria, and consequently to humans.

Molecular epidemiology and mechanisms of antibiotic resistance in Enterococcus spp., Staphylococcus spp., and Streptococcus spp. in Africa: a systematic review from a One Health perspective

A systematic review of antibiotic-resistant Gram-positive bacteria in Africa from a One Health perspective is lacking. Here, we report result from a search for English-language articles on the resistance mechanisms and clonality of Gram-positive bacteria in Africa between 2007 and 2019 reported in PubMed, Web of Science, ScienceDirect, and African Journals OnLine; 172 studies from 22 different African countries were identified. Resistance genes, such as mecA, erm(B), erm(C), tet(M), tet(K), tet(L), vanB, vanA, vanC, and tet(O), were found to be common. Staphylococcus spp., Enterococcus spp., and Streptococcus spp. were the main species reported by the studies, with clones such as Staphylococcus aureus ST5 (n = 218 isolates), ST8 (n = 127 isolates), ST80 (n = 133 isolates), and ST88 (n = 117 isolates), and mobile genetic elements such as IS16 (n = 28 isolates), IS256 (n = 96), Tn916 (n = 107 isolates), and SCCmec (n = 4437 isolates) identified. SCCmec IV (n = 747 isolates) was predominant, followed by SCCmec III (n = 305 isolates), SCCmec II (n = 163 isolates), SCCmec V (n = 135 isolates), and SCCmec I (n = 79 isolates). Resistance to penicillin (n = 5926 isolates), tetracycline (n = 5300 isolates), erythromycin (n = 5151 isolates), rifampicin (n = 3823 isolates), gentamycin (n = 3494 isolates), sulfamethoxazole/trimethoprim (n = 3089 isolates), and ciprofloxacin (n = 2746 isolates) was common in most reports from 22 countries. Clonal dissemination of resistance across countries and between humans, animals, and the environment was observed. Resistance rates ranged from 1.4% to 100% for 15 of the studies; 10 were One Health-related studies. Strict infection control measures, antimicrobial stewardship, and periodic One Health epidemiological surveillance studies are needed to monitor and contain the threat of increasing antibiotic resistance in Africa.

Methicillin-Resistant Staphylococcus aureus ST80 Clone: A Systematic Review

This review assessed the molecular characterization of the methicillin-resistant Staphylococcus aureus (MRSA)-ST80 clone with an emphasis on its proportion of total MRSA strains isolated, PVL production, spa-typing, antibiotic resistance, and virulence. A systematic review of the literature was conducted on MRSA-ST80 clone published between 1 January 2000 and 31 August 2019. Citations were chosen for a review of the full text if we found evidence that MRSA-ST80 clone was reported in the study. For each isolate, the country of isolation, the sampling period, the source of isolation (the type of infection, nasal swabs, or extra-human), the total number of MRSA strains isolated, number of MRSA-ST80 strains, antibiotic resistance patterns, PVL production, virulence genes, and spa type were recorded. The data from 103 articles were abstracted into an Excel database. Analysis of the data showed that the overall proportion of MRSA-ST80 has been decreasing in many countries in recent years. The majority of MRSA-ST80 were PVL positive with spa-type t044. Only six reports of MRSA-ST80 in extra-human niches were found. This review summarizes the rise of MRSA-ST80 and the evidence that suggests that it could be in decline in many countries.

Distribution of Toxinogenic Methicillin-Resistant and Methicillin-Susceptible Staphylococcus aureus from Different Ecological Niches in Algeria

The diffusion of Panton-Valentine leukocidin (PVL)-positive methicillin-resistant S. aureus (MRSA) is a health problem in Algeria. The objectives of the study were to investigate the global distribution of methicillin-susceptible S. aureus (MSSA) and MRSA isolates in different ecological niches in this country. In total, 2246 samples were collected from humans, livestock, wild animals, pets, food products and the aquatic environment, from 12 Algerian provinces. A total of 312 S. aureus were detected from 2446 samples (12.7%) in the screened niches. We observed the emergence of toxinogenic S. aureus representing 41% of the isolates. Among them, we noted the diffusion of ST80-IV CA-MRSA PVL + strains isolated in human, animals, and food and genetic diversity of MSSA PVL + isolates. This study suggests an alarming dissemination of MRSA-ST80 PVL + in both human and extra-human sources in Algeria. Moreover, MSSA may become a permanent reservoir of the PVL genes necessary for human infections.

Epidemiology of common resistant bacterial pathogens in the countries of the Arab League

No uniformly organised collection of data regarding antimicrobial resistance has occurred in the countries of the Arab League. 19 countries of the Arab League have published data for antimicrobial susceptibility for the WHO priority organisms, and seven of 14 of these organisms are included in this Review (Escherichia coli, Klebsiella spp, Pseudomonas aeruginosa, Acinetobacter baumannii, Salmonella spp, Staphylococcus aureus, and Streptococcus pneumoniae). Although E coli and Klebsiella spp resistance to third-generation cephalosporins is common in all countries, with prevalence reaching more than 50% in Egypt and Syria, carbapenem resistance is emerging, albeit with a prevalence of less than 10%. Conversely, a large amount of carbapenem resistance has been reported for P aeruginosa and A baumannii across the Arab League, reaching 50% and 88% of isolates in some countries. As for Salmonella spp, the prevalence of fluoroquinolone resistance has exceeded 30% in several areas. With regards to the Gram-positive pathogens, the prevalence of meticillin resistance in S aureus is reported to be between 20% and 30% in most countries, but exceeds 60% in Egypt and Iraq. The prevalence of penicillin non-susceptibility among pneumococci has reached more than 20% in Algeria, Egypt, Morocco, Saudi Arabia, and Tunisia. These findings highlight the need for structured national plans in the region to target infection prevention and antimicrobial stewardship.

High levels of Staphylococcus aureus and MRSA carriage in healthy population of Algiers revealed by additional enrichment and multisite screening

The purpose of the research is to characterize Staphylococcus aureus colonization in healthy population of Algiers, to assess the impact on diagnostic performance of systematic additional broth enrichment, and to ascertain the additional benefits of multiple site screening. In order to more accurately determine the prevalence of S. aureus colonization, the swab specimens from multiple screening sites were incubated in brain-heart broth before agar plating. From 2009 to 2011, 1176 samples were collected from 459 participants (201 adults and 258 children). The additional enrichment detection step significantly increased S. aureus detection rates (p < 0.0001). S. aureus nasal detection was positive in 37.8% of adults, and the addition of throat samplings significantly increased the S. aureus detection rate up to 54.7% (p < 0.001). S. aureus nasal detection was positive in 37.6% of children. The addition of throat samplings in children significantly increased the S. aureus detection rate up to 53.1% (p < 0.001) and that of anal samplings up to 59.7%. The overall prevalence of methicillin-resistant S. aureus was 5.2% (3% of adults and 7% of children). spa typing of all isolates revealed a diverse but strongly clonal S. aureus population structure. This approach involving multiple anatomical sampling sites and an additional enrichment of the swabs before conventional culture significantly increases the detection rate of S. aureus carriers and may prove valuable to improve global S. aureus infection prevention.

Staphylococcal cassette chromosome mec typing and mecA sequencing in methicillin-resistant staphylococci from Algeria: a highly diversified element with new mutations in mecA

Genetic mechanisms of methicillin resistance are still relevant in staphylococci. The aims of this study are to assess the possible exchanges of staphylococcal cassette chromosome mec (SCCmec) among isolates of methicillin-resistant staphylococci (MRS) and to check for known or new mutations in mecA DNA. A total of 35 MRS non-repetitive isolates were recovered, including 20 Staphylococcushaemolyticus, 7 Staphylococcusaureus, 4 Staphylococcussciuri, 2 Staphylococcussaprophyticus and 1 isolate each of Staphylococcusxylosus and Staphylococcuslentus. Only 16 of the 35 strains were assigned to known SCCmec types: 7 SCCmec VII, 6 SCCmec IV and 3 SCCmec III, with possible horizontal transfer of the SCCmec VII from methicillin-resistant S. haemolyticus to methicillin-susceptible S. aureus. mecA gene sequencing in ten selected isolates allowed description of nine punctual mutations, seven of which were reported for the first time. The most frequent mutation was G246E, identified in isolates of methicillin-resistant S. aureus, S. sciuri, S. saprophyticus and S. lentus. These results emphasized the high degree of genetic diversity of SCCmec element in MRS and describe new missense mutations in mecA, which might be important in understanding the evolution of methicillin and new β-lactam resistance.