Phylogenetic and antimicrobial drug resistance analysis of Vibrio cholerae O1 isolates from Ghana.

We investigated the evolution, phylogeny and antimicrobial resistance of Vibrio cholerae O1 isolates (VCO1) from Ghana. Outbreak and environmental sources of VCO1 were characterized, whole-genome sequenced and compared to globally available seventh pandemic (7P) strains of V. cholerae at SNP resolution. Final analyses included 636 isolates. Novel Ghanaian isolates clustered into three distinct clades (clades 1, 2 and 3) in wave 3 of the 7P lineage. The closest relatives of our novel Ghanaian isolates were from Benin, Cameroon, Togo, Niger and Nigeria. All novel Ghanaian isolates were multi-drug resistant. Environmental isolates clustered into clade 2, despite being isolated years later, showing the possibility of persistence and re-emergence of older clades. A lag phase of several years from estimated introduction to reported cases suggests pathogen persistence in the absence of reported cholera cases. These results highlight the importance of deeper surveillance for understanding transmission routes between bordering countries and planning tailored vaccination campaigns in an effort to eradicate cholera.

Bloodstream Infections at Two Neonatal Intensive Care Units in Ghana: Multidrug Resistant Enterobacterales Undermine the Usefulness of Standard Antibiotic Regimes.

BACKGROUND: Bloodstream infections (BSIs) are a major cause of morbidity and mortality in hospitalized neonates. Data on antibiotic resistance in neonatal BSIs and their impact on clinical outcomes in Africa are limited. METHODS: We conducted a prospective cohort study at 2 tertiary level neonatal intensive care units (NICUs) in Ghana. All neonates admitted to the NICUs were included from October 2017 to September 2019. We monitored BSI rates and analyzed the effect of BSI and antibiotic resistance on mortality and duration of hospitalization. RESULTS: Of 5433 neonates included, 3514 had at least one blood culture performed and 355 had growth of a total of 368 pathogenic microorganisms. Overall incidence of BSI was 1.0 (0.9-1.1) per 100 person days. The predominant organisms were Klebsiella pneumoniae 49.7% (183/368) and Streptococcus spp. 10.6% (39/368). In addition, 512 coagulase negative Staphylococci were isolated but considered probable contaminants. Among K. pneumoniae, resistance to gentamicin and amikacin was 91.8% and 16.4%, respectively, while carbapenem resistance was 4.4%. All-cause mortality among enrolled neonates was 19.7% (1066/5416). The mortality rate was significantly higher in neonates with BSI compared with culture-negative neonates in univariate analysis (27.9%, n = 99/355 vs. 16.5%, n = 520/3148; hazard ratio 1.4, 95% confidence interval 1.07-1.70) but not in multivariate analysis. CONCLUSION: The diversity of etiologic agents and the high-risk of antibiotic resistance suggest that standard empirical treatment is unlikely to improve the outcome of BSIs in low and middle income. Such improvements will depend on access to reliable clinical microbiologic services.

High rates of multi-drug resistant gram-negative organisms associated with surgical site infections in a teaching hospital in Ghana.

BACKGROUND: There is limited data to guide the prevention and management of surgical site infections (SSI) in low- and middle-income countries. We prospectively studied aetiological agents associated with SSI and their corresponding antibiotic susceptibility patterns in a tertiary hospital in Ghana. METHODS: As part of a cohort study carried out at the surgical department of the Korle Bu Teaching Hospital (KBTH) from July 2017 to April 2019, wound swabs were collected from patients diagnosed with SSI. Isolates cultured from the wound swabs were identified by MALDI TOF and susceptibility testing was conducted according to EUCAST 2020 guidelines. Clinical data were monitored prospectively. RESULTS: Of 4577 patients, 438 developed an SSI and 352 microbial isolates were cultured. Isolates were predominantly Gram negative (286, 81%), a pattern seen for all kinds of surgery and all wound classes. The most common species included Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus and Acinetobacter baumannii. The majority of organisms were multi-drug resistant including 86% of E. coli, 52% of A. baumannii and 86% of K. pneumoniae; and 65% (17/26) of the cefotaxime-resistant K. pneumoniae were extended spectrum ß-lactamase producing. One of 139 E. coli, 15 of 49 P. aeruginosa, and 6 of 23 A. baumannii were meropenem resistant, but no clonal pattern was found. There was a 1% (5/428) prevalence of methicillin-resistant S. aureus. CONCLUSIONS: The predominance of Gram-negative organisms and the high level of multi-drug resistance indicate a need to re-evaluate antibiotic prophylaxis and treatment protocols in surgical practice in low- and middle-income countries.

Oxacillinase-181 Carbapenemase-Producing Klebsiella pneumoniae in Neonatal Intensive Care Unit, Ghana, 2017-2019.

We sequenced 29 carbapenemase-producing Klebsiella pneumoniae isolates from a neonatal intensive care unit in Ghana. Twenty-eight isolates were sequence type 17 with blaOXA-181 and differed by 0-32 single-nucleotide polymorphisms. Improved surveillance and infection control are needed to characterize and curb the spread of multidrug-resistant organisms in sub-Saharan Africa.

High Carriage Rates of Multidrug-Resistant Gram-Negative Bacteria in Neonatal Intensive Care Units From Ghana.

BACKGROUND: Carriage of multidrug resistant (MDR) Gram-negative bacteria (GN) in hospitalized neonates may increase the risk of difficult-to-treat invasive infections at neonatal intensive care units (NICUs). Data on MDRGN carriage among hospitalized newborns in Africa are limited. METHODS: We conducted a cross-sectional study at the NICUs of 2 tertiary hospitals in Ghana. Swabs from the axilla, groin, perianal region, and the environment were cultured, GN were identified, and antibiotic susceptibility was tested. We obtained blood culture isolates from neonates with sepsis. Whole-genome sequencing was used to characterize carbapenemase-producing Klebsiella pneumoniae. Typing was done by multilocus sequence typing (MLST) and single nucleotide polymorphism (SNP) analysis. RESULTS: A total of 276 GN were isolated from 228 screened neonates. Pathogenic GN were cultured in 76.8% (175 of 228) of neonates. Klebsiella spp (41.7%; 115 of 276) and Escherichia coli (26.4%; 73 of 276) were the commonest organisms. Carriage rates of MDRGN and third-generation cephalosporin resistant organisms were 49.6% (113 of 228) and 46.1% (105 of 228), respectively. Among Klebsiella spp, 75.6% (87 of 115) phenotypically expressed extended-spectrum ß-lactamase activity, whereas 15.6% expressed carbapenemase and harbored bla- OXA-181 and bla- CTX-M-15. Overall, 7.0% (16 of 228) of neonates developed GN bloodstream infection. In 2 of 11 neonates, sequencing showed the same identity between carriage and the bloodstream isolate. Length of stay before specimen collection and antibiotic use were independently associated with carriage rates, which increased from 13% at admission to 42% by day 2 and reached a plateau at 91% by day 15. CONCLUSIONS: High carriage rates of MDRGN, including carbapenemase-producing enterobacterales may be an emerging problem in NICUs in Africa.

Antimicrobial resistance (AMR) and molecular characterization of Neisseria gonorrhoeae in Ghana, 2012-2015.

Neisseria gonorrhoeae antimicrobial resistance (AMR) surveillance is essential for tracking the emergence and spread of AMR strains in local, national and international populations. This is crucial for developing or refining treatment guidelines. N. gonorrhoeae multiantigen sequence typing (NG-MAST) is beneficial for describing the molecular epidemiology of gonococci at national and international levels. Elucidation of AMR determinants to ß-lactam drugs, is a means of monitoring the development of resistance. In Ghana, little is known about the current gonococcal AMR prevalence and no characterization of gonococcal isolates has been previously performed. In this study, gonococcal isolates (n = 44) collected from five health facilities in Ghana from 2012 to 2015, were examined using AMR testing, NG-MAST and sequencing of penA. High rates of resistance were identified to tetracycline (100%), benzylpenicillin (90.9%), and ciprofloxacin (81.8%). One isolate had a high cefixime MIC (0.75 µg/ml). Twenty-eight NG-MAST sequence types (STs) were identified, seventeen of which were novel. The isolate with the high cefixime MIC contained a mosaic penA-34 allele and belonged to NG-MAST ST1407, an internationally spreading multidrug-resistant clone that has accounted for most cefixime resistance in many countries. In conclusion, AMR testing, NG-MAST, and sequencing of the AMR determinant penA, revealed high rates of resistance to tetracycline, benzylpenicillin, and ciprofloxacin; as well as a highly diverse population of N. gonorrhoeae in Ghana. It is imperative to continue with enhanced AMR surveillance and to understand the molecular epidemiology of gonococcal strains circulating in Ghana and other African countries.

Pneumococcal carriage among children under five in Accra, Ghana, five years after the introduction of pneumococcal conjugate vaccine.

BACKGROUND: The study objective was to determine the carriage and serotype distribution of Streptococcus pneumoniae among children in Accra, Ghana, five years after the introduction of the pneumococcal conjugate vaccine (PCV-13) in 2012. METHODS: Nasopharyngeal swab samples were collected from 410 children below 5 years of age in Accra, Ghana, from September to December, 2016. Pneumococcal isolates were identified by optochin sensitivity and bile solubility. Serotyping was performed using the latex agglutination kit and Quellung reaction. The isolates were furthermore tested for antimicrobial susceptibility for different antimicrobials, including penicillin (PEN). Twelve isolates including seven non-typeable (NT) isolates were characterized using whole-genome sequencing analysis (WGS). RESULTS: The overall carriage prevalence was found to be 54% (95% CI, 49-59%), and 20% (95% CI, 49-59%) of the children were carrying PCV-13 included serotypes, while 37% (95% CI, 33-42%) of the children were carrying non-PCV-13 serotypes. Based on the serotype distribution, 33% of all observed serotypes were included in PCV-13 while 66% were non-PCV-13 serotypes. The dominating non-PCV-13 serotypes were 23B, 16F, and 11A followed by PCV-13 serotypes 23F and 19F. The PCV-13 covers the majority of resistant isolates in Accra. A proportion of 22.3% of the isolates showed intermediate resistance to penicillin G, while only one isolate showed full resistance. Forty-five isolates (20.5%) were defined as multidrug-resistant (MDR) as they were intermediate/resistant to three or more classes of antimicrobials. Of the seven NT isolates characterized by WGS, four showed highest match to genotype 38, while the remaining three showed highest match to genotype 14. Four MDR serotype 19A isolates were found to be MLST 320. CONCLUSION: PCV-13 introduced in Ghana did not eliminate PCV-13 covered serotypes, and the carriage rate of 54% in this study is similar to carriage studies from pre PCV-13 period. However, the penicillin non-susceptible isolates have been reduced from 45% of carriage isolates before PCV-13 introduction to 22.3% of the isolates in this study. Continuous monitoring of serotype distribution is important, and in addition, an evaluation of an alternative vaccination schedule from 3 + 0 to 2 + 1 will be important to consider.

Antibiotic use in a tertiary healthcare facility in Ghana: a point prevalence survey.

Background: The global rise and spread of antibiotic resistance is limiting the usefulness of antibiotics in the prevention and treatment of infectious diseases. The use of antibiotic stewardship programs guided by local data on prescribing practices is a useful strategy to control and reduce antibiotic resistance. Our objective in this study was to determine the prevalence and indications for use of antibiotics at the Korle-Bu Teaching Hospital Accra, Ghana. Methods: An antibiotic point prevalence survey was conducted among inpatients of the Korle-Bu Teaching Hospital between February and March 2016. Folders and treatment charts of patients on admission at participating departments were reviewed for antibiotics administered or scheduled to be administered on the day of the survey. Data on indication for use were also collected. Prevalence of antibiotic use was determined by dividing the number of inpatients on antibiotics at the time of survey by the total number of patients on admission. Results: Of the 677 inpatients surveyed, 348 (51.4%, 95% CI, 47.6-55.2) were on treatment with antibiotics. Prevalence was highest among Paediatric surgery where 20/22 patients (90.9%, 95% CI, 70.8-98.9) were administered antibiotics and lowest among Obstetrics patients with 77/214 (36%, 95% CI, 29.5-42.8). The indications for antibiotic use were 245/611 (40.1%) for community-acquired infections, 205/611 (33.6%) for surgical prophylaxis, 129/611 (21.1%) for healthcare associated infections and 33/611 (5.4%) for medical prophylaxis. The top five antibiotics prescribed in the hospital were metronidazole 107 (17.5%), amoxicillin-clavulinic acid 82 (13.4%), ceftriaxone 17(12.1%), cefuroxime 61 (10.0%), and cloxacillin 52 (8.5%) respectively. Prevalence of meropenem and vancomycin use was 12(2%) and 1 (.2%) respectively. The majority of patients 181 (52%) were being treated with two antibiotics. Conclusion: This study indicated a high prevalence of antibiotic use among inpatients at the Korle-Bu Teaching Hospital. Metronidazole was the most commonly used antibiotic; mainly for surgical prophylaxis. There is the need to further explore factors contributing to the high prevalence of antibiotic use and develop strategies for appropriate antibiotic use in the hospital.

Physicians' knowledge, attitudes, and perceptions concerning antibiotic resistance: a survey in a Ghanaian tertiary care hospital.

BACKGROUND: Understanding the knowledge, attitudes and practices of physicians towards antibiotic resistance is key to developing interventions aimed at behavior change. The survey aimed to investigate physicians' knowledge and attitudes towards antibiotic resistance in a tertiary-care hospital setting in Ghana. METHODS: We conducted a cross-sectional respondent-driven survey using a 40-item, anonymous, voluntary, traditional paper-and-pencil self-administered questionnaire among 159 physicians at Korle-Bu Teaching Hospital. Single and multi-factor analysis were conducted to assess the study objectives. RESULTS: The survey was completed by 159 of 200 physicians (response rate of 79.5%). Of physicians, 30.1% (47/156) perceived antibiotic resistance as very important global problem, 18.5% (29/157) perceived it as very important national problem and only 8.9% (14/157) thought it as a very important problem in their hospital. Methicillin resistant Staphylococcus aureus was the most known about antibiotic resistant bacteria of public health importance followed by extended-spectrum beta-lactamase-producing Enterobacteriaceae, carbapenem resistant Enterobacteriaceae (CRE) and vancomycin resistant enterococci (VRE). In multiple logistic regression analysis, senior physicians were nearly 3 times more likely to know about CRE than junior physicians. The odds of knowing about VRE increased over 4.5 times from being a junior to becoming senior physician. Among junior physicians, age had no associated effect on their knowledge of VRE or CRE. CONCLUSIONS: Physicians in this survey showed variable knowledge and perceptions on antibiotic resistance. Introducing educational programs on antibiotic resistance would be a useful intervention and should focus on junior physicians.

In Vitro Susceptibility of Mycobacterium ulcerans Isolates to Selected Antimicrobials.

Background. The current definitive treatment of Buruli ulcer with antibiotics makes the issue of antimicrobial drug resistance an unavoidable one. This is as a result of drug misuse by health personnel and patients' noncompliance to treatment regimen. Monitoring of these factors and screening for new effective antimicrobials are crucial to effective management of Buruli ulcer disease. This study therefore investigated the inhibitory activity of some antibiotics against isolates of Mycobacterium ulcerans. Methods. Activity of eight antibiotics was tested against twelve M. ulcerans isolates (2 reference strains and 10 clinical isolates). The anti-M. ulcerans activities were determined by the agar dilution method and the minimum inhibitory concentrations (MICs) were determined by the agar proportion method. Results. All antimicrobials investigated had activity against M. ulcerans isolates tested. The MICs ranged from 0.16 µg/mL to 2.5 µg/mL. Azithromycin recorded the highest inhibitory activity at a mean MIC of 0.39 µg/mL, whilst clofazimine a second-line antileprosy drug, recorded the lowest at a mean MIC of 2.19 µg/mL. Among the four antituberculosis drugs, rifampicin had the highest activity with a mean MIC of 0.81 µg/mL. Conclusion. Azithromycin could be considered as a lucrative alternative to existing treatment methods for inhibiting M. ulcerans in Ghana.

Evaluating decontamination protocols for the isolation of Mycobacterium ulcerans from swabs.

BACKGROUND: Mycobacterium ulcerans (M. ulcerans) is the causative agent of Buruli Ulcer (BU) disease. In order to inhibit the growth of the microbial contaminants during culture of M. ulcerans, it is necessary to decontaminate BU samples with effective chemical agents. This study aimed at investigating some selected chemicals as potential decontamination agents for the isolation of M. ulcerans from swabs. RESULTS: Povidone iodine at 0.5 and 1% exhibited the lowest contamination and recovery rate for microbial contaminants and M. ulcerans. The most effective decontamination method was the protocol using 2% cetylpyridinium chloride/4% sodium chloride (recovery rate = 53%, contamination rate = 14%). The observed difference between the recovery rate of 2% CPC/4% NaC and the other protocols was however not statistically significant (p = 0.76). CONCLUSIONS: Two percent (2%) cetylpyridinium chloride/4% sodium chloride can be conveniently used as an alternative decontamination method for the isolation of M. ulcerans from swabs.

High rates of cerebral toxoplasmosis in HIV patients presenting with meningitis in Accra, Ghana.

Background: Data on adult meningitis among patients infected with the human immunodeficiency virus (HIV) is scarce in western sub-Saharan Africa, including Ghana. Methods: HIV-infected adults with a provisional diagnosis of meningitis were consecutively enrolled, between August 2014 and January 2016. After patient data collection, cerebrospinal fluid (CSF) was obtained and evaluated for microbiological aetiologies, cell counts and biochemistry. Caregiver clinicians provided limited data for inpatients at the end-point of discharge or death. Results: Complete data sets from 84 patients were analysed (inpatients=63, outpatients=21). Median age was 40 years with 56% (47/84) being females. Only 30% (25/84) of the patients were on antiretroviral therapy (ART). CD4+ T-cell count was available for 81% (68/84) of patients and 61.9% (52/84) had counts below 150 cells/µL [median and interquartile range=56 (13.8-136)]. Microbiological aetiologies were detected in 60.7% (51/84) patients with the following distribution-Toxoplasmosis (25%), Epstein-Barr virus (28.6%), Cytomegalovirus and Cryptococcus (2.4%) each. Co-infection was identified in 20.7% (17/84) of the patients. Conclusion: Patients presenting with symptoms of meningitis had advanced HIV/AIDS, a quarter of whom had cerebral toxoplasmosis or infection with EBV. A high index of suspicion, laboratory exclusion of cryptococcal meningitis and prompt patient management with anti-toxoplasmosis empiric therapy may thus be required for optimal treatment.

Laboratory-based nationwide surveillance of antimicrobial resistance in Ghana.

Global efforts are underway to combat antimicrobial resistance (AMR). A key target in this intervention is surveillance for local and national action. Data on AMR in Ghana are limited, and monitoring of AMR is nonexistent. We sought to generate baseline data on AMR, and to assess the readiness of Ghana in laboratory-based surveillance. Biomedical scientists in laboratories across Ghana with capacity to perform bacteriological culture were selected and trained. In-house standard operating protocols were used to perform microbiological investigations on clinical specimens. Additional microbiological tests and data analyses were performed at a centralized laboratory. Surveillance data were stored and analyzed using WHONET program files. A total of 24 laboratories participated in the training, and 1,598 data sets were included in the final analysis. A majority of the bacterial species were isolated from outpatients (963 isolates; 60.3%). Urine (617 isolates; 38.6%) was the most common clinical specimen cultured, compared to blood (100 isolates; 6.3%). Ten of 18 laboratories performed blood culture. Bacteria isolated included Escherichia coli (27.5%), Pseudomonas spp. (14.0%), Staphylococcus aureus (11.5%), Streptococcus spp. (2.3%), and Salmonella enterica serovar Typhi (0.6%). Most of the isolates were multidrug-resistant, and over 80% of them were extended-spectrum beta-lactamases-producing. Minimum inhibitory concentration levels at 50% and at 90% for ciprofloxacin, ceftriaxone, and amikacin on selected multidrug-resistant bacteria species ranged between 2 µg/mL and >256 µg/mL. A range of clinical bacterial isolates were resistant to important commonly used antimicrobials in the country, necessitating an effective surveillance to continuously monitor AMR in Ghana. With local and international support, Ghana can participate in global AMR surveillance.

Multidrug-Resistant Streptococcus pneumoniae Isolates from Healthy Ghanaian Preschool Children.

Streptococcus pneumoniae is the cause of high mortality among children worldwide. Antimicrobial treatment and vaccination are used to control pneumococcal infections. In Ghana, data on antimicrobial resistance and the prevalence of multidrug-resistant pneumococcal clones are scarce; hence, the aim of this study was to determine the antibiogram of S. pneumoniae recovered from Ghanaian children younger than six years of age and to what extent resistances were due to the spread of certain sero- and multilocus sequence typing (MLST) types. The susceptibility of 115 pneumococcal isolates, recovered in a previous study, to six antimicrobials was determined by disk diffusion test. Overall, 90.4% of isolates were intermediate penicillin resistant, 99.1% were trimethoprim resistant, 73.0% were tetracycline resistant, and 33.9% were sulfamethoxazole resistant. Low resistance was recorded for erythromycin (2.6%) and cefotaxime (5.2%). Overall, 72.2% of isolates were resistant to penicillin (I or R) and at least two other antimicrobials. MLST of 20 isolates showing resistance to at least four antimicrobials revealed a high diversity documented by 16 different clones, none of which had previously been associated with multidrug resistance. The resistances found may have emerged due to nonprudent antimicrobial use practices and there is a need to monitor and promote prudent antimicrobial usage in Ghana.

Clonal distribution of pneumococcal serotype 19F isolates from Ghana.

Streptococcus pneumoniae is a major cause of morbidity and mortality worldwide. Pneumococcal strains are classified according to their capsular polysaccharide and more than 90 different serotypes are currently known. In this project, three distinct groups of pneumococcal carriage isolates from Ghana were investigated; isolates from healthy children in Tamale and isolates from both healthy and children attending the outpatient department at a hospital in Accra. The isolates were previously identified and characterized by Gram staining, serotyping and susceptibility to penicillin. In this study, isolates of the common serotype 19F were further investigated by Multi-Locus Sequence Typing (MLST). Overall, 14 different Sequence Types (STs) were identified by MLST, of which nine were novel based on the international MLST database. Two clones within serotype 19F seem to circulate in Ghana, a known ST (ST 4194) and a novel ST (ST 9090). ST 9090 was only found in healthy children in Accra, whereas ST 4194 was found equally in all children studied. In the MLST database, other isolates of ST 4194 were also associated with serotype 19F, and these isolates came from other West African countries. The majority of isolates were penicillin intermediate resistant. In conclusion, two clones within serotype 19F were found to be dominating in pneumococcal carriage in Accra and Tamale in Ghana. Furthermore, it seems as though the clonal distribution of serotype 19F may be different from what is currently known in Ghana in that many new clones were identified. This supports the importance of continued monitoring of pneumococcal carriage in Ghana and elsewhere when vaccines, e.g., PCV-13, have been introduced to monitor the possible future spread of antimicrobial resistant clones.

Penicillin resistance and serotype distribution of Streptococcus pneumoniae in Ghanaian children less than six years of age.

BACKGROUND: The objective of this study was to determine the prevalence of nasopharyngeal carriage, serotype distribution, and penicillin resistance of Streptococcus pneumoniae in children ≤ 6 years of age in Ghana. METHODS: A cross-sectional study was carried out on a cluster-randomized sample of children ≤ 6 years of age attending nurseries and kindergartens in Accra and Tamale, Ghana. Basic data on age, sex and exposure to antimicrobials in the previous month were collected on all study subjects. Nasopharyngeal swabs were obtained from participants and all pneumococcal isolates were characterized by serotyping and their penicillin resistance determined. RESULTS: The overall prevalence of pneumococcal carriage among the children was 34% in Accra and 31% in Tamale. The predominant serotypes were 19F, 6B, 23F, and 6A with 23% of the isolates being non-typable in Accra and 12% in Tamale. Only two isolates (serotypes 19F and 6B) from Tamale had a MIC >2 µg/ml and were classified as fully penicillin resistant with 45% of the isolates having intermediate resistance. CONCLUSIONS: These findings indicate that the 13-valent pneumococcal conjugate vaccine (PCV-13) recently introduced in Ghana will cover 48% and 51% of the serotypes identified in Accra and Tamale, respectively. The 23-valent pneumococcal polysaccharide vaccine (PPV-23) will cover 54% of all serotypes detected. The two penicillin resistant isolates (MIC 32 µg/ml) were serotypes included in both PCV-13 and PPV-23. A nationwide monitoring system of penicillin susceptibility patterns and pneumococcal serotypes is recommended.

High levels of extended-spectrum beta-lactamases in a major teaching hospital in Ghana: the need for regular monitoring and evaluation of antibiotic resistance.

Infections with bacteria producing extended-spectrum beta-lactamases (ESBLs) are increasing across Africa. This study reports on ESBL-producing Enterobacteriaceae as significant causes of infections and antibiotic resistance at Korle-Bu Teaching Hospital in Accra, Ghana. Of 300 isolates examined, 49.3% produced ESBLs. The prevalence of ESBLs was significantly high among isolates from neonates (28 of 43, 65.1%; relative risk = 1.62, 95% confidence interval = 1.33-2.13, P = 0.002) and adult patients > 65 years of age (36 of 51, 70.5%; relative risk = 1.89, 95% confidence interval = 1.41-2.40, P = 0.001). A marked increase in minimum inhibitory concentrations of ESBL-positive species was noticed compared with those for the other strains. Using these concentrations, we found that 26 (17%) ESBL producers were resistant to two or more antibiotics (aminoglycosides, fluoroquinolones, sulfonamide, and carbapenems) whereas 5 (3.2%) non-ESBL producers were multidrug resistant. Regular ESBL detection and evaluation of antibiotic resistance may help reduce the spread of ESBLs and antibiotic resistance in Ghana.

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.

Regional dissemination of a trimethoprim-resistance gene cassette via a successful transposable element.

BACKGROUND: Antimicrobial resistance is a growing international problem. We observed a 50% increase in the prevalence of trimethoprim resistance among fecal Escherichia coli from healthy Nigerian students between 1998 and 2005, a trend to increase that continued in 2009. METHODS AND FINDINGS: A PCR-based screen revealed that 131 (43.1%) of isolates obtained in Nigeria in 2005 and 2009 carried integron-borne dfrA cassettes. In the case of 67 (51.1%) of these isolates, the cassette was a class 1-integron-borne dfrA7 gene, which has been reported at high prevalence from E. coli isolates from other parts of Africa. Complete sequencing of a 27 Kb dfrA7-bearing plasmid from one isolate located the dfrA7 gene within a Tn21-type transposon. The transposon also contained an IS26-derived bla/sul/str element, encoding resistance to ß-lactams, sulphonamides and streptomycin, and mercury resistance genes. Although the plasmid backbone was only found in 12 (5.8%) of trimethoprim-resistant isolates, dfrA7 and other transposon-borne genes were detected in 14 (16.3%) and 32 (26.3%) of trimethoprim resistant isolates collected in Nigeria in 2005 and 2009, respectively. Additionally, 37 (19.3%) of trimethoprim-resistant E. coli isolates collected between 2006 and 2008 from Ghana were positive for the dfrA7 and a transposon marker, but only 4 (2.1%) harbored the plasmid backbone. CONCLUSIONS: Our data point to transposition as a principal mechanism for disseminating dfrA7 among E. coli from Nigeria and Ghana. On-going intensive use of the affordable broad-spectrum antibacterials is likely to promote selective success of a highly prevalent transposable element in West Africa.

Epidemiological aspects of non-human antibiotic usage and resistance: implications for the control of antibiotic resistance in Ghana.

OBJECTIVES: To provide insights into the epidemiology of antibiotic usage in animal husbandry in Ghana and its effect on resistance. METHODS: Three hundred and ninety-five randomly sampled commercial livestock keepers who practised intensive or extensive farming were interviewed about their antibiotic usage practices using a structured questionnaire. Escherichia coli isolated from stool specimens of farmers and their animals were tested against eight antibiotics using the Kirby Bauer method. RESULTS: Ninety-eight percent (387) of the farmers used antibiotics on animals and the main purpose was to prevent infections in animals; 41% applied antibiotics monthly. The overall prevalence of multiple drug resistance among the E. coli isolates was 91.6%; rates in human and animal isolates were 70.6% and 97.7%, respectively. The prevalence of resistance in animal isolates to the various drugs ranged from 60.8% (amikacin) to 95.7% (ampicillin); the prevalence of resistance in human isolates to the drugs ranged from 2% (cefuroxime) to 94.1% (gentamicin). Animal E. coli isolates showed higher resistance than that of human isolates for five of eight drugs tested. CONCLUSION: It is concluded that antibiotic usage in animal husbandry in Ghana is more driven by the interest of livestock keepers to prevent and treat animal infections than growth enhancement. Both animal and human E. coli showed high levels of antibiotic resistance, although resistance of animal isolates appeared to be higher than that of humans. There is the need for the development of an antibiotic-resistance management programme in Ghana that will focus simultaneously on human and animal use of antibiotics.