Multidrug-Resistant Gram-Negative Bacteria Contaminating Raw Meat Sold in Accra, Ghana

BACKGROUND

Efforts to combat antimicrobial resistance (AMR) should be based on the One Health approach, involving human health, animal health, and the environment. In Ghana, previous studies on AMR have given little attention to animal source food, a major route of transmission of antibiotic-resistant zoonotic pathogens. The aim of this study was to investigate the occurrence of multidrug-resistant (MDR) bacteria in meat sold in Accra.

METHODS

This was a cross-sectional study in which 270 meat samples (90 each of beef, goat meat, and chicken) were collected, and investigated for contamination with multidrug-resistant bacteria. The bacteria were subjected to susceptibility testing against amikacin (30 µg), ampicillin (10 µg), amoxicillin-clavulanate (20/10 µg), cefuroxime (30 µg), ceftriaxone (30 µg), ceftazidime (30 µg), cefepime (30 µg), ciprofloxacin (5 µg), trimethoprim-sulfamethoxazole (1.25/23.75 µg), ertapenem (10 µg), meropenem (10 µg), imipenem (10 µg), tigecycline (15 µg), and gentamicin (10 µg).

RESULTS

Thirty-two different types of bacteria, totalling 558, were isolated, the predominant being Escherichia coli (44.6%), Aeromonas hydrophila (19.9%), Vibrio cholerae (3.4%), Aeromonas veronii (3.2%), and Klebsiella pneumoniae (3.1%). The prevalence of MDR among the contaminating bacteria was 14.9%. The MDR distribution among the predominant bacteria was Escherichia coli (18.7%), Aeromonas hydrophila (11.1%), Vibrio cholerae and Aeromonas veronii (0.0% each), and K. pneumoniae (5.6%). Moreover, 2.0% of the contaminating bacteria were extended-spectrum beta-lactamase (ESBL) producers, all of which occurred in the chicken samples, and their distribution was: Escherichia coli (1.3%), Klebsiella pneumoniae, Pantoea spp., Enterobacter cloacae, and Serratia plymuthica (0.2% each).

CONCLUSIONS

The meat samples were heavily contaminated with Escherichia coli and Aeromonas hydrophila, and less frequently, with Vibrio cholerae, Klebsiella pneumoniae, and other organisms. The prevalence of multidrug-resistant bacteria was moderate (14.9%), while that of ESBL producers was low (2%).

Genetic relatedness in carbapenem-resistant isolates from clinical specimens in Ghana using ERIC-PCR technique

AIM

Enterobacterial repetitive intergenic consensus (ERIC) sequence analysis is a powerful tool for epidemiological analysis of bacterial species. This study aimed to determine the genetic relatedness or variability in carbapenem-resistant isolates by species using this technique.

METHODS

A total of 111 non-duplicated carbapenem-resistant (CR) Gram-negative bacilli isolates from a three-year collection period (2012-2014) were investigated by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) in four selected hospital laboratories in Ghana. The isolates were also screened for carbapenemase and extended spectrum β-lactamase genes by PCR.

RESULTS

A proportion of 23.4% (26/111) of the genomic DNA extracts were carriers of PCR-positive carbapenemase genes, including 14.4% blaNDM-1, 7.2% blaVIM-1 and 1.8% blaOXA-48. The highest prevalence of carbapenemase genes was from non-fermenters, Acinetobacter baumannii and Pseudomonas aeruginosa. For the ESBL genes tested, 96.4% (107/111) of the CR isolates co-harboured both TEM-1 and SHV-1 genes. The ERIC-PCR gel analysis exhibited 1 to 8 bands ranging from 50 to 800 bp. Band patterns of 93 complex dissimilarities were visually distinguished from the 111 CR isolates studied, while the remaining 18 showed band similarities in pairs.

CONCLUSION

Overall, ERIC-PCR fingerprints have shown a high level of diversity among the species of Gram-negative bacterial pathogens and specimen collection sites in this study. ERIC-PCR optimisation assays may serve as a suitable genotyping tool for the assessment of genetic diversity or close relatedness of isolates that are found in clinical settings.

Phenotypic and Genotypic Characterization of Carbapenem-Resistant Gram-Negative Bacilli Pathogens from Hospitals in Ghana

In Ghana, surveillance efforts on antibiotic resistance so far have not covered carbapenem resistance. In this study, our aim was to apply phenotypic and genotypic methods to identify and characterize carbapenem-resistant (CR) Gram-negative bacteria from the hospital environment in Ghana. A collection of 3840 isolates of Gram-negative bacilli infections from various clinical specimens was screened for carbapenem resistance by disc diffusion for imipenem, meropenem, and doripenem. Minimum Inhibitory Concentration (MIC) of the CR isolates was determined by E-test for the three carbapenems. All the CR isolates were further screened for carbapenemase activity by modified Hodge and boronic acid disc synergy tests. The CR isolates were investigated for the presence of carbapenemase and extended-spectrum beta-lactamase genes by PCR and confirmed by sequencing. The overall prevalence of CR isolates was 2.9% (111/3840). Based on the disc diffusion test, prevalence of resistance to carbapenems were doripenem (75%), imipenem (66.7%), and meropenem (58%). The highest measurable MIC levels (≥32 μg/mL) were observed in 56.8% of CR isolates with the nonfermenters, Pseudomonas aeruginosa (24.3%) and Acinetobacter species (18.9%), disproportionately represented. Phenotypic identification of carbapenamase activity occurred in 18.9% of the CR isolates by the modified Hodge test and 2.7% by Boronic acid disc synergy test; 21.6% exhibited carbapenemase production by both methods. All the CR isolates carried ESBL genes (blaTEM and blaSHV), whereas 23.4% were carriers of carbapenemase genes, of which 14.4% were blaNDM-1, 7.2% blaVIM-1, and 1.8% blaOXA-48. Phylogenetically, the CR isolates were diverse and showed limited relatedness to isolates from other geographical regions.

Methicillin Resistant Staphylococcus aureus and Extended Spectrum Beta-lactamase Producing Enterobacteriaceae: A Therapeutic Challenge in the 21st Century

Antimicrobial resistance is one of the greatest global threats to human health in recent times and it limits the achievement of several of the Sustainable Development Goals. Methicillin-ResistantStaphylococcus aureus(MRSA) and Extended-Spectrum Beta-Lactamase (ESBL) producingEnterobacteriaceaeare among the most important multidrug resistant bacterial pathogens. MRSA and ESBL-producingEnterobacteriaceaehave evolved significantly over the last few decades with important clinical and epidemiological implications. Given the slow progress of development of new antibiotics in recent times, it is likely that these multidrug resistant pathogens will have a greater impact on public health in the 21stCentury, unless other effective control measures are instituted. Effective infection control strategies coupled with antibiotic stewardship programs are required to limit the spread and burden of MRSA and ESBL-producingEnterobacteriacae.

Carbapenem Resistance: A Review

Carbapenem resistance is a major and an on-going public health problem globally. It occurs mainly among Gram-negative pathogens such as Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii, and may be intrinsic or mediated by transferable carbapenemase-encoding genes. This type of resistance genes are already widespread in certain parts of the world, particularly Europe, Asia and South America, while the situation in other places such as sub-Saharan Africa is not well documented. In this paper, we provide an in-depth review of carbapenem resistance providing up-to-date information on the subject.

Distribution of Candida species among HIV-positive patients with oropharyngeal candidiasis in Accra, Ghana

INTRODUCTION

Oropharyngeal candidiasis is a common occurrence in the course of human immunodeficiency virus (HIV) disease progression. Changes in the clinical severity of oropharyngeal candidiasis and type of Candida species profile may be a reflection of immunological changes in patients. The aim of this study was to undertake a baseline Candida species identification for future reference.

METHODOLOGY

Oral swabs of 267 HIV-infected patients with oropharyngeal candidiasis were cultured and Candida species were identified by API 32 C.

RESULTS

A total of 201 (75.3%) Candida species and 10 (3.7%) non candida fungi were identified. Twenty different Candida species were isolated. Candida albicans was the most prevalent species (68.5%) followed by C. tropicalis (7.4%), C. krusei (6.4%), C. parapsilosis (3.0%) and C. sake (2.5%). Other species ranged from 0.5% to 1.5%. Positive culture was independent of whether patients were on anti-retroviral therapy or not.

CONCLUSION

Of all Candida isolates, 68.5% were identified as C. albicans. Since other uncommon species were also isolated, it may be necessary in this group of patients to identify Candida species causing severe infections.

Aetiology of suppurative corneal ulcers in Ghana and south India, and epidemiology of fungal keratitis

BACKGROUND

A multicentre study was carried out in Ghana and southern India to determine the aetiology of suppurative keratitis in two regions located at similar tropical latitudes. Studies of fungal keratitis from the literature were reviewed.

METHODS

Patients presenting at rural and urban eye units with suspected microbial keratitis were recruited to the study. Corneal ulceration was defined as loss of corneal epithelium with clinical evidence of infection with or without hypopyon. Microscopy and culture were performed on all corneal specimens obtained.

RESULTS

1090 patients were recruited with suspected microbial keratitis between June 1999 and May 2001. Overall the principal causative micro-organisms in both regions were filamentous fungi (42%): Fusarium species and Aspergillus species were the commonest fungal isolates. Pseudomonas species were most frequently isolated from cases of bacterial keratitis in Ghana but in India the commonest bacterial isolates were streptococci.

CONCLUSION

Infections of the cornea due to filamentous fungi are a frequent cause of corneal damage in developing countries in the tropics and are difficult to treat. Microscopy is an essential tool in the diagnosis of these infections. A knowledge of the "local" aetiology within a region is of value in the management of suppurative keratitis in the event that microscopy cannot be performed.