Antimicrobial resistance among Gram-positive pathogens in Saudi Arabia

Physicians' attitudes, knowledge, and practices regarding antibiotic prescriptions

OBJECTIVES

Inappropriate and overuse of antimicrobials, incorrect dosing, and extended duration are some of the leading causes of antibiotic-resistance that have led to the development of antimicrobial resistance (AMR). We aimed to evaluate knowledge, attitudes, and practices regarding rational antibiotic prescribing among physicians in a teaching hospital in Oman, with the goal of identifying knowledge gaps and interventions that could lead to judicious use of antimicrobials and reduce the emergence of resistant organisms METHODS: A cross-sectional study assessing physicians' knowledge of and attitudes towards prescribing antibiotics was conducted at the Royal Hospital from 15 January to 31 March 2020. Likert scales were used to evaluate physicians' awareness and perception of personal performance regarding the care of patients with infections and rational use of antibiotics.

RESULTS

Inadequate hand washing was regarded as the most important factor contributing to AMR (51.6%), followed by widespread use of antibiotics (49%), prescribing broad-spectrum antibiotics (47.3%), lack of effective narrow-spectrum antibiotics (47.3%), inappropriate duration of antibiotic therapy (46.2%), inappropriate empirical choice of antibiotics (45.1%), poor access to information on local antibiotic resistance patterns (40.8%), and inadequate restrictions on antibiotic prescribing (34.4%). Other factors contributing to AMR such as lack of local hospital guidelines on antibiotic usage, random mutations in microbes, patient demands and expectations for antibiotics, and the role of pharmaceutical companies in advertising and promoting use of antibiotics were deemed important by 33.3%, 26.8%, 22.5% and 20.4%, respectively.

CONCLUSIONS

AMR is a global health threat with significant effect on the health system and the economy. Misuse and overuse of antimicrobials remain the main drivers for the development of drug-resistant pathogens. Identifying knowledge gaps and planning interventions that could lead to judicious use of antimicrobials including establishing an Antimicrobial Stewardship Program are of paramount importance in reducing AMR in the twenty-first century and beyond.

Whole-Genome Sequencing of Staphylococcus aureus and Staphylococcus haemolyticus Clinical Isolates from Egypt

Infections caused by antibiotic-resistant Staphylococcus are a global concern. This is true in the Middle East, where increasingly resistant Staphylococcus aureus and Staphylococcus haemolyticus strains have been detected. While extensive surveys have revealed the prevalence of infections caused by antibiotic-resistant staphylococci in Europe, Asia, and North America, the population structure of antibiotic-resistant staphylococci recovered from patients and clinical settings in Egypt remains uncharacterized. We performed whole-genome sequencing of 56 S. aureus and 10 S. haemolyticus isolates from Alexandria Main University Hospital; 46 of the S. aureus genomes and all 10 of the S. haemolyticus genomes carry mecA, which confers methicillin resistance. Supplemented with additional publicly available genomes from the other parts of the Middle East (34 S. aureus and 6 S. haemolyticus), we present the largest genomic study to date of staphylococcal isolates from the Middle East. These genomes include 20 S. aureus multilocus sequence types (MLST), including 3 new ones. They also include 9 S. haemolyticus MLSTs, including 1 new one. Phylogenomic analyses of each species' core genome largely mirrored those of the MLSTs, irrespective of geographical origin. The hospital-acquired spa t037/ST239-SCCmec III/MLST CC8 clone represented the largest clade, comprising 22% of the S. aureus isolates. Like S. aureus genome surveys of other regions, these isolates from the Middle East have an open pangenome, a strong indicator of gene exchange of virulence factors and antibiotic resistance genes with other reservoirs. Our genome analyses will inform antibiotic stewardship and infection control plans in the Middle East. IMPORTANCE Staphylococci are understudied despite their prevalence within the Middle East. Methicillin-resistant Staphylococcus aureus (MRSA) is endemic to hospitals in Egypt, as are other antibiotic-resistant strains of S. aureus and S. haemolyticus. To provide insight into the strains circulating in Egypt, we performed whole-genome sequencing of 56 S. aureus and 10 S. haemolyticus isolates from Alexandria Main University Hospital. Through analysis of these genomes, as well as all available S. aureus and S. haemolyticus genomes from the Middle East (n = 40), we were able to produce a picture of the diversity in this region more complete than those afforded by traditional molecular typing strategies. For example, we identified 4 new MLSTs. Most strains harbored genes associated with multidrug resistance, toxin production, biofilm formation, and immune evasion. These data provide invaluable insight for future antibiotic stewardship and infection control within the Middle East.

Prevalence of Multidrug-Resistant Methicillin-Resistant Staphylococcus aureus in Northeastern Saudi Hospitals

Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for serious threats to human health, causing various syndromes worldwide. Here, our purpose was to estimate the prevalence of nosocomial MRSA among isolates from King Khalid Hospital (KKH) and Maternity and Children Hospital (MCH) at Hafar Al-Batin Governorate, Saudi Arabia, and to determine the resistance of these isolates to common antibiotics used for treatment. One-hundred clinical specimens were collected from admitted patients during a six month period, and subjected to MRSA screening using traditional microbiological techniques. Antimicrobial susceptibility testing (AST) was also performed and confirmed by the VITEK2 automated system. Among the 37 S. aureus strains isolated from KKH, 23 (62.16%) were identified as MRSA. In MCH, 38 (60.31%) out 63 isolated strains were identified as MRSA. According to AST, few MRSA strains were resistant to teicoplanin, fosfomycin, linezolid, and mupirocin in both hospitals. Vancomycin resistance was not detected in any of the MRSA strains. Twelve MRSA strains from KKH and 17 strains from MCH were considered multidrug resistant (MDR). In conclusion, prevention is critical to reduce the high prevalence of MRSA.

Eleven-Year surveillance of methicillin-resistant Staphylococcus aureus infections at an Academic Health Centre

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) is an important human pathogen associated with nosocomial and community infections. There is a continual focus on the epidemiology of this public health threat owing to the increase in its spread and rapid development of resistance.

AIM

We aimed to demonstrate the time trend of antibiotic resistance by describing the epidemiology of MRSA infections at an academic health centre.

METHODOLOGY

We retrospectively reviewed cases during an 11-year period (from January 2009 to December 2019) with positive cultures for MRSA from various clinical sites in King Fahad Hospital of the University, to understand their clinical and microbiological profiles. Screening and colonisation samples were excluded.

RESULTS

A total of 1338 MRSA isolates were identified, with an increasing trend from 5.2% to 14.5% during 2009-2019. Skin and soft tissue samples were the most common source (52.4%) of MRSA infections. Vancomycin activity remained stable against MRSA, and only one isolate showed resistance to linezolid (< 1%). A significant reduction in susceptibility to clindamycin (p = 0.003), trimethoprim-sulfamethoxazole (p = 0.001), and rifampin (p < 0.0001) was detected over the study period.

CONCLUSIONS

MRSA infections still represent a significant burden on healthcare systems. Our data support the need for constant local and regional surveillance to devise relevant protocols to manage MRSA infections. Empirical therapy needs to consider the changing antimicrobial susceptibility trends among MRSA isolates.

Insecticide resistance to insect growth regulators, avermectins, spinosyns and diamides in Culex quinquefasciatus in Saudi Arabia

BACKGROUND

Culex quinquefasciatus is not only a biting nuisance but also an important vector of fatal diseases. In Saudi Arabia, management measures to control this mosquito and thereby prevent associated disease transmission have focused on insecticides. Nevertheless, information on the resistance status of C. quinquefasciatus is insufficient, especially concerning insecticides containing novel classes of insecticides.

METHODS

We evaluated six insecticides belonging to four classes of insecticides (insect growth regulators [3], avermectins [1], diamides [1] and spinosyns [1]) for toxicity and resistance in eight C. quinquefasciatus populations (from Ishbiliya, Al-Masfa, Al-Masanie, Al-Washlah, Al-Nakhil, Irqah, Al-Suwaidi and Al-Ghanemiya) following World Health Organisation protocols.

RESULTS

Resistance status ranging from susceptibility/low resistance to high resistance, in comparison with the susceptible strain, was detected for cyromazine in the eight C. quinquefasciatus populations: Ishbiliya (resistance ratio [RR] = 3.33), Al-Masfa (RR = 4.33), Al-Masanie (RR = 3.67), Al-Washlah (RR = 2.33), Al-Nakhil (RR = 5.33), Irqah (RR = 7.00), Al-Suwaidi (RR = 21.33) and Al-Ghanemiya (RR = 16.00). All C. quinquefasciatus populations exhibited a high level of resistance to diflubenzuron (RR = 13.33-43.33), with the exception of Al-Nakhil which exhibited moderate resistance (RR = 10.00). Susceptibility/low resistance to high resistance was observed for triflumuron in the eight C. quinquefasciatus populations: Ishbiliya (RR = 0.50), Al-Ghanemiya (RR =  3.00), Al-Suwaidi (RR =  10.00), Al-Masfa (RR =  5.00), Al-Masanie (RR =  10.00), Al-Nakhil (RR =  5.00), Irqah (RR =  5.00) and Al-Washlah (RR =  15.00). Susceptibility/low resistance was assessed for abamectin, chlorantraniliprole and spinosad in all C. quinquefasciatus populations, with RR ranges of 0.25-3.50, 0.17-2.19, and 0.02-0.50, respectively. However, the population collected from Irqah showed high resistance to chlorantraniliprole (RR = 11.93).

CONCLUSIONS

The detection of widespread resistance to insect growth regulators in C. quinquefasciatus highlights an urgent need to establish integrated vector management strategies. Our results may facilitate the selection of potent insecticides for integrated vector management programmes for C. quinquefasciatus.

Community Pharmacists' Views of the Enforced Antibiotics Dispensing Law and Its Impact on Oral Antibiotics Sales in Saudi Arabia

Objective(s)

The aim of this study was to explore community pharmacists’ views toward the antibiotics dispensing law that was enforced in May 2018 and bans the sale of antibiotics without a prescription in community pharmacy settings in Saudi Arabia. Moreover, the potential impact of the law enforcement on the sales of oral antibiotics in Saudi Arabia was also explored.

Methods

A questionnaire-based cross-sectional study was conducted between September 2019 and March 2020 in Riyadh, Saudi Arabia. A multistage sampling technique was used to recruit community pharmacists from different districts. Pharmacists who consented to participate and reported practicing prior to the law enforcement were interviewed about their views of the law using a 14-item newly developed questionnaire. The annual sales of oral antibiotics for the years of 2017, 2018, and 2019 were retrieved from the Saudi Food and Drug Authority (SFDA) database.

Results

Two hundred and eighty six pharmacists consented to participate and met the inclusion criteria. After the law enforcement, approximately 51% of the participants reported that the percentage of patients seeking antibiotics without a prescription is less than 25%. Moreover, the majority (87.41%) reported a drop in the sales of antibiotics. Additionally, about 90% of the participants believed that the rate of inappropriate use of antibiotics will decrease as a result of the law enforcement. About 41% of the participants reported that the law has negatively impacted their pharmacies’ profits. The sales of oral antibiotics have seen a 16.6% drop in the year of 2019 as compared to 2017.

Conclusion

The antibiotics dispensing law is favorably perceived among community pharmacists in Saudi Arabia despite some concerns about its impact on their sales. Exploring different business models that delink the profits from the volume of antibiotics sales is necessary for this vital industry to thrive.

High Burden of Resistant Gram Negative Pathogens Causing Device-associated Healthcare Infections in a Tertiary Care Setting in Saudi Arabia, 2008-2016

OBJECTIVES

There is local and regional deficiency in the data examining the contribution of resistant pathogens to device-associated healthcare-associated infections (DA-HAIs). The objective was to examine such data in a multi-hospital system in Saudi Arabia in comparison with the US National Health Surveillance Network (NHSN).

METHODS

Surveillance of DA-HAIs was prospectively conducted between 2008 and 2016 in four hospitals of Ministry of National Guard Health Affairs. Consecutive NHSN reports were used for comparisons. Definitions and methodology of DA-HAIs and bacterial resistance were based on NHSN.

RESULTS

A total 1260 pathogens causing 1141 DA-HAI events were included. Gram negative pathogens (GNPs) were responsible for 62.5% of DA-HAIs, with a significantly higher Klebsiella, Pseudomonas, Acinetobacter, and Enterobacter than NHSN hospitals. Approximately 28.3% of GNPs and 23.5% of gram positive pathogens (GPPs) had some type of resistance. Nearly 34.3% of Klebsiella were resistant to third/fourth generation cephalosporins, 4.8% of Enterobacteriaceae were carbapenem-resistant (CRE), 24.4% of Staphylococcus aureus were methicillin-resistant (MRSA), and 21.9% of Enterococci were vancomycin-resistant (VRE). Multidrug resistance (MDR) was 65.0% in Acinetobacter, 26.4% in Escherichia coli, 23.0% in Klebsiella, and 14.9% in Pseudomonas. Resistant GNPs including cephalosporin-resistant Klebsiella, MDR Klebsiella, and MDR Escherichia coli were significantly more frequent while resistant GPPs including MRSA and VRE were significantly less frequent than NHSN hospitals.

CONCLUSION

The current findings showed heavier and more resistant contribution of GNPs to DA-HAIs in Saudi hospitals compared with American hospitals. The higher resistance rates in Klebsiella and Escherichia coli are alarming and call for effective antimicrobial stewardship programs.

High contribution and impact of resistant gram negative pathogens causing surgical site infections at a multi-hospital healthcare system in Saudi Arabia, 2007-2016

Background

Despite being largely preventable, surgical site infections (SSIs) are still one of the most frequent healthcare-associated infections. The presence of resistant pathogens can further augment their clinical and economic impacts. The objective was to estimate the distribution and resistance in SSI pathogens in Saudi Arabia and to compare them to the US National Healthcare Safety Network (NHSN) hospitals.

Methods

Targeted SSI surveillance was prospectively conducted on several surgical procedures done between 2007 and 2016 in four hospitals of Ministry of National Guard Health Affairs. Definitions and methodology of SSI and bacterial resistance were based on NHSN.

Results

A total 492 pathogens causing 403 SSI events were included. The most frequent pathogens were Staphylococcus aureus (22.8%), Pseudomonas aeruginosa (20.1%), Klebsiella spp. (12.2%), and Escherichia coli (12.2%), with marked variability between surgeries. Approximately 30.3% of Staphylococcus aureus was methicillin-resistant (MRSA), 13.0% of Enterococcus spp. was vancomycin-resistant (VRE), and 5.5% of Enterobacteriaceae were carbapenem resistant (CRE). The highest multidrug-resistant (MDR) GNPs were Acinetobacter spp. (58.3%), Klebsiella spp. (20.4%) and Escherichia coli (16.3%). MRSA was significantly less frequent while cephalosporin-resistant Klebsiella spp., MDR Klebsiella spp., and MDR Escherichia coli were significantly more frequent in our hospitals compared with NHSN hospitals.

Conclusion

GNPs in a tertiary care setting in Saudi Arabia are responsible for more than 60% of SSI with more resistant patterns than Western countries. This information may be critical to secure resources and ensure support for caregivers and healthcare leaders in implementing antimicrobial stewardship programs and evidence-based SSI preventive practices.

Clinical Relevance and Antimicrobial Profiling of Methicillin-Resistant Staphylococcus aureus (MRSA) on Routine Antibiotics and Ethanol Extract of Mango Kernel (Mangifera indica L.)

Methicillin-resistant Staphylococcus aureus (MRSA) is known for serious health problems. Testing new inexpensive natural products such as mango kernel (Mangifera indica L., Anacardiaceae) may provide alternative and economically viable anti-MRSA drugs. In the current study, we screened clinical isolates from Aseer Central Hospital, Saudi Arabia, during 2012–2017 for MRSA and tested an ethanolic extract of mango kernel for anti-MRSA activity. Brief confirmation of MRSA was performed by the Vitek 2 system, while antibiotic sensitivity of strains was tested for their clinical relevance. The In vitro disc diffusion method was used to test the anti-MRSA activity of the ethanolic mango kernel extract. The antimicrobial activity of mango kernel was compared to that of standard drugs (oxacillin and vancomycin). Of the identified 132 S. aureus strains, 42 (31.8%) were found to be MRSA and their prevalence showed a clear increase during the last two years (2016-2017; p < 0.001). MRSA strains showed 100% sensitivity to vancomycin, teicoplanin, linezolid, tetracycline, daptomycin, tigecycline, and tobramycin and 100% resistance to ampicillin and 98% to penicillin. The ethanolic extracts of mango kernel were found active against both S. aureus and the MRSA strains. Inhibitory activities (mean ± SE) were achieved at concentrations of 50 mg/mL (20.77 ± 0.61), 5 mg/mL (16.18 ± 0.34), and 0.5 mg/mL (8.39 ± 0.33) exceeding that of vancomycin (p=0.0162). MRSA strains were sensitive to mango kernel extracts when compared to vancomycin. Therefore, ethanolic extracts of mango kernel can be escalated to animal model studies as a promising leading anti-MRSA drug candidate and can be an economic alternative to high-priced synthetic antibiotics.

Bacteriostatic and Bactericidal Activity of Deer Musk on Multidrug Resistance Bacteria

BACKGROUND AND OBJECTIVE

Infecting agents (e.g., bacteria, fungi, virus and parasite) have comprised high levels of multidrug resistance (MDR) with increased morbidity and mortality; so the main aim of this study was to investigate and demonstrate the antimicrobial activity of deer musk on multidrug-resistance bacteria and to proof that musk had a bacteriostatic and bactericidal effects against MDR bacteria.

MATERIALS AND METHODS

Deer musk evaluated 11 multi-drug resistance (MDR) species were selected, namely, Staphylococcus capitis, Staphylococcus aureus, Klebsiella pneumonia, Escherichia coli, Acinetobacter baumanni, Pseudomonas aeruginosa, Proteus mirabilis, Serratia marcescens, Streptococcus agalactiae, Streptococcus pyogenes and Enterococcus faecalis the MDR strain were tested by means of disk diffusion, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) by the time-kill method recommendation by CLSI. In addition, the antimicrobial susceptibility of 8 commonly used antimicrobials was examined on the same MDR bacterial strains.

RESULTS

The minimum inhibitory concentration MIC and MBC values were <2% (v/v) against all MDR strains except Pseudomonas aeruginosa, but the deer musk has bacteriostatic and bactericidal activity against Pseudomonas aeruginosa at >2% (v/v), in addition changes was observed in the morphological form of the bacterial colonies in of most of MDR bacteria such as Staphylococcus aureus, Streptococcus agalactiae, Pseudomonas aeruginosa and Klebsiella baumanni and indicating that the musk had an effect on bacterial cellular membranes.

CONCLUSION

The findings of this study indicated that deer musk has a bacteriostatic and bactericidal effects on the growth of all tested MDR bacteria.

Pattern of antibiotic prescription among dentists in Riyadh, Saudi Arabia

AIM

The aim of the present study was to investigate the pattern of antibiotic prescription and dentists' awareness about the recent guidelines for antibiotic prescription.

METHODS

This cross-sectional study was conducted among 282 dentists practicing in Riyadh, Saudi Arabia. The data were collected from 20 randomly-selected dental clinics from each of the five administrative blocks in Riyadh. In addition, data were also collected from four tertiary care centers and three academic universities. The questionnaire measured the antibiotic prescription pattern of the dentists and their choice of antibiotics for various dental conditions.

RESULTS

Amoxicillin was the most commonly prescribed antibiotic. More than 70% of dentists prescribed antibiotics for dental patients with various cardiac conditions. Bivariate analysis showed that female dentists had significantly higher mean scores for ideal prescription pattern (P = .04) compared to male dentists. Saudi nationals, especially those working in the government sector were found to have better prescription pattern compared with others (P = .02). Dentists with higher educational qualifications (board certificate and above) had a more ideal prescription pattern than other dentists (P = .04).

CONCLUSION

Inappropriate antibiotic prescription practice was highly prevalent in this population.

Antimicrobial resistance among pilgrims: a retrospective study from two hospitals in Makkah, Saudi Arabia

OBJECTIVE

To identify commonly reported community-acquired organisms and antimicrobial resistance patterns exhibited by Gram-positive and Gram-negative pathogens among pilgrims visiting emergency care departments in Makkah.

METHOD

The study was designed as a retrospective audit of all patients (pilgrims) admitted to two hospitals and residing in the city of Makkah, Saudi Arabia.

RESULTS

Among 374 isolates, Gram-negative pathogens accounted for 280 (75%), while the remaining 94 (25%) were Gram-positive organisms. Among all isolated pathogens, the highest resistance was observed for amoxicillin-clavulanic acid. Klebsiella pneumoniae had the highest resistance to amoxicillin-clavulanic acid and ampicillin. Most of the organisms were sensitive to tobramycin except Acinetobacter baumannii (n=3, 50%), Escherichia coli (n=4, 57%), and K. pneumoniae (n=6, 46%).

CONCLUSION

Overall, a high resistance was observed for beta-lactam antibiotics. In addition, a high resistance was noted for ceftazidime with A. baumannii species (n=16, 77%). However, for quinolones, the highest resistance to ciprofloxacin was observed for E. coli, A. baumannii, methicillin-resistant Staphylococcus aureus, and K. pneumoniae.

The Saudi Thoracic Society pneumococcal vaccination guidelines-2016

Streptococcus pneumoniae (pneumococcus) is the leading cause of morbidity and mortality worldwide. Saudi Arabia is a host to millions of pilgrims who travel annually from all over the world for Umrah and the Hajj pilgrimages and are at risk of developing pneumococcal pneumonia or invasive pneumococcal disease (IPD). There is also the risk of transmission of S. pneumoniae including antibiotic resistant strains between pilgrims and their potential global spread upon their return. The country also has unique challenges posed by susceptible population to IPD due to people with hemoglobinopathies, younger age groups with chronic conditions, and growing problem of antibiotic resistance. Since the epidemiology of pneumococcal disease is constantly changing, with an increase in nonvaccine pneumococcal serotypes, vaccination policies on the effectiveness and usefulness of vaccines require regular revision. As part of the Saudi Thoracic Society (STS) commitment to promote the best practices in the field of respiratory diseases, we conducted a review of S. pneumoniae infections and the best evidence base available in the literature. The aim of the present study is to develop the STS pneumococcal vaccination guidelines for healthcare workers in Saudi Arabia. We recommend vaccination against pneumococcal infections for all children <5 years old, adults ≥50 years old, and people ≥6 years old with certain risk factors. These recommendations are based on the presence of a large number of comorbidities in Saudi Arabia population <50 years of age, many of whom have risk factors for contracting pneumococcal infections. A section for pneumococcal vaccination before the Umrah and Hajj pilgrimages is included as well.

Methicillin-Resistant Staphylococcus Aureus in Saudi Arabia: Genotypes Distribution Review

Methicillin-resistant Staphylococcus Aureus (MRSA) infections in hospital have obviously imposed a significant burden of morbidity and mortality, and strain on healthcare resources. Here, we review the genotype distribution of these pathogens in the Kingdom of Saudi Arabia (KSA). A PubMed literature search (until May 2014) specified 12 articles that characterized MRSA clones in KSA. Only two regions (Riyadh and Damamm) were represented in ten articles. Data from these articles showed that the pandemic Vienna/Hungarian/Brazilian clone (CC8/ST239-III) is the most frequent in Saudi regions (Riyadh and Damamm). Several other clones such as Barnim/UK-EMRSA-15 (CC22-IV), Southwest Pacific clone (ST30-IV) and European community-associated-MRSA clone (CC80-IV) have been detected in the Riyadh region. A variety of MRSA clones is beginning to circulate in Saudi hospitals. Continued collection and molecular characterization of MRSA is crucial for the effective prevention and treatment.

Removal of bacterial contaminants and antibiotic resistance genes by conventional wastewater treatment processes in Saudi Arabia: Is the treated wastewater safe to reuse for agricultural irrigation?

This study aims to assess the removal efficiency of microbial contaminants in a local wastewater treatment plant over the duration of one year, and to assess the microbial risk associated with reusing treated wastewater in agricultural irrigation. The treatment process achieved 3.5 logs removal of heterotrophic bacteria and up to 3.5 logs removal of fecal coliforms. The final chlorinated effluent had 1.8 × 10(2) MPN/100 mL of fecal coliforms and fulfils the required quality for restricted irrigation. 16S rRNA gene-based high-throughput sequencing showed that several genera associated with opportunistic pathogens (e.g. Acinetobacter, Aeromonas, Arcobacter, Legionella, Mycobacterium, Neisseria, Pseudomonas and Streptococcus) were detected at relative abundance ranging from 0.014 to 21 % of the total microbial community in the influent. Among them, Pseudomonas spp. had the highest approximated cell number in the influent but decreased to less than 30 cells/100 mL in both types of effluent. A culture-based approach further revealed that Pseudomonas aeruginosa was mainly found in the influent and non-chlorinated effluent but was replaced by other Pseudomonas spp. in the chlorinated effluent. Aeromonas hydrophila could still be recovered in the chlorinated effluent. Quantitative microbial risk assessment (QMRA) determined that only chlorinated effluent should be permitted for use in agricultural irrigation as it achieved an acceptable annual microbial risk lower than 10(-4) arising from both P. aeruginosa and A. hydrophila. However, the proportion of bacterial isolates resistant to 6 types of antibiotics increased from 3.8% in the influent to 6.9% in the chlorinated effluent. Examples of these antibiotic-resistant isolates in the chlorinated effluent include Enterococcus and Enterobacter spp. Besides the presence of antibiotic-resistant bacterial isolates, tetracycline resistance genes tetO, tetQ, tetW, tetH, tetZ were also present at an average 2.5 × 10(2), 1.6 × 10(2), 4.4 × 10(2), 1.6 × 10(1) and 5.5 × 10(3) copies per mL of chlorinated effluent. Our study highlighted that potential risks associated with the reuse of treated wastewater arise not only from conventional fecal indicators or known pathogens, but also from antibiotic-resistant bacteria and genes.

Molecular characterization of carbapenemase production among gram-negative bacteria in saudi arabia

We characterized the molecular basis of carbapenemase production in carbapenem-resistant Gram-negative bacteria isolated from hospitalized patients from Saudi Arabia in the year 2012. Isolates were collected from across the Kingdom and phenotypically tested for carbapenemase production. Polymerase chain reaction detection of carbapenemase genes was also performed. Our results indicate that in Saudi Arabia, OXA-48 and NDM-1 are the dominant carbapenemases among Enterobacteriaceae with low prevalence of VIM. The latter is the most prevalent metallo-beta-lactamase in Pseudomonas aeruginosa, whereas oxacillinases, OXA-23 in particular, are the dominant carbapenemases in Acinetobacter baumannii. No KPC or IMP genes were detected. Our study is the first report of OXA-48, NDM-1, and VIM-4 enzymes in Enterobacter from the Kingdom. Also it is the first report of OXA-72 and NDM-1 in A. baumannii in Saudi Arabia, and the coexistence of blaOXA-23 and blaNDM-1 genes in this species in the country. Awareness of the role of international travel in the spread of carbapenem-resistant determinants in the Kingdom, as well as effective infection control interventions in hospitals and strict antimicrobial stewardship in healthcare facilities and the community are keys to combat the rise of carbapenemase producers in the Kingdom.

A prospective, observational, epidemiological evaluation of the aetiology and antimicrobial susceptibility of acute otitis media in Saudi children younger than 5years of age

Background: Information regarding acute otitis media (AOM) aetiology is important for developing effective vaccines. Here, bacterial aetiology and antimicrobial susceptibility of AOM were determined in young Saudi children.

Methods: Children aged 3–60 months with a new episode of AOM, who had not received antibiotics or had received antibiotics for 48–72 h but remained symptomatic, were enrolled in this prospective, observational, epidemiological study in Riyadh. Middle ear fluid (MEF) samples were collected by tympanocentesis or from spontaneous otorrhea, and tested for the presence of Streptococcus pneumoniae, Haemophilus influenzae, Streptococcus pyogenes and Moraxella catarrhalis. Antimicrobial susceptibility of the identified pathogens was assessed using E-tests.

Results: Between June 2009 and May 2011, 66 children were enrolled. S. pneumoniae was detected in 6 episodes and non-typeable H. influenzae (NTHi) in 8 episodes. Moreover, Staphylococcus aureus, which is an uncommon cause of AOM, was detected in 17 episodes. Pneumococcal serotypes were 7F (n = 2), 23F (n = 2), 19F (n = 1) and 15F (n = 1). Susceptibility to cefotaxime was observed in all pneumococcal and H. influenzae isolates, to cefuroxime in 4/6 pneumococcal and 8/8 H. influenzae isolates, and to penicillin in 5/6 pneumococcal isolates.

Conclusions:S. pneumoniae and NTHi were major bacterial contributors for AOM in Saudi children.

High burden of antimicrobial drug resistance in Asia

The rapid development of antimicrobial resistance among micro-organisms is a serious public health concern. Moreover, the dissemination of antibiotic-resistant bacteria makes this issue a global problem, and Asia is no exception. For example, since New Delhi metallo-β-lactamase (NDM)-producing Enterobacteriaceae were identified in India, further spread of NDM has become a worldwide threat. However, the epidemiology of antibiotic-resistant bacteria in Asia may be different to other regions, and clinical condition may be worse than in western countries. Antibiotic-resistant bacteria, including community-acquired and hospital-acquired meticillin-resistant Staphylococcus aureus (MRSA), vancomycin-intermediate S. aureus (VISA), vancomycin-resistant enterococci, macrolide- and penicillin-resistant Streptococcus pneumoniae, extend-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae, carbapenem-resistant Enterobacteriaceae, and multidrug-resistant Pseudomonas aeruginosa and Acinetobacter spp., are becoming prevalent in many countries in Asia. Moreover, the prevalence of each antibiotic-resistant bacterium in each country is not identical. This review provides useful information regarding the critical condition of antibiotic resistance in Asia and emphasises the importance of continuous surveillance of resistance data.

National surveillance of antimicrobial resistance among Gram-positive bacteria in Saudi Arabia

BACKGROUND

Antimicrobial-resistant Gram-positive bacteria are important causes of serious infections.

METHODS

Between January and December 2009, we examined clinical Gram-positive isolates from 24 hospitals across Saudi Arabia.

RESULTS

Among the 13750 isolates, Staphylococcus aureus (62.3%) was the commonest, followed by non-group A beta-haemolytic streptococci (14.8%), group A beta-haemolytic streptococci (7.1%), coagulase-negative staphylococci (6.6%), pneumococci (6.0%), and enterococci (3.1%). Resistance rates were high among S. aureus (methicillin-resistant S. aureus: 32%), coagulase-negative staphylococci (oxacillin: 63%) and pneumococci (penicillin G: 33%; erythromycin: 26%; ceftriaxone: 11%); low among enterococci (vancomycin: 1%) and among beta-haemolytic streptococci. Resistance rates varied between regions, but comparison was complicated by differences in antibiotics tested. Many relevant antibiotics were tested against few isolates (e.g. ampicillin, vancomycin, and high-level gentamicin versus enterococci) while unhelpful tests were widely performed (e.g. cefotaxime, ceftriaxone, and imipenem versus staphylococci.

CONCLUSION

Resistance is widespread in staphylococci and pneumococci, but not enterococci and beta-haemolytic streptococci in Saudi Arabia. Rationalization of antibiotic panels tested is urgently needed.