Prevalence and antimicrobial susceptibility pattern of Salmonella enterica serovar Typhi and Salmonella enterica serovar Paratyphi among febrile patients at Karamara Hospital, Jigjiga, eastern Ethiopia

Uncovering the growing burden of enteric fever: A molecular analysis of Salmonella Typhi antimicrobial resistance

Enteric fever, a persistent public health challenge in developing regions, is exacerbated by suboptimal socioeconomic conditions, contaminated water and food sources, and insufficient sanitation. This study delves into the antimicrobial susceptibility of Salmonella Typhi, uncovering the genetic underpinnings of its resistance. Analyzing 897 suspected cases, we identified a significant prevalence of typhoid fever, predominantly in males (58.3 %) and younger demographics. Alarmingly, our data reveals an escalation in resistance to both primary and secondary antibiotics, with cases of multi-drug resistant (MDR) and extensively drug-resistant (XDR) S. Typhi reaching 14.7 % and 43.4 %, respectively, in 2021. The Multiple Antibiotic Resistance (MAR) index exceeded 0.2 in over half of the isolates, signaling widespread antibiotic misuse. The study discerned 47 unique antibiotic resistance patterns and pinpointed carbapenem and macrolide antibiotics as the remaining effective treatments against XDR strains, underlining the critical need to preserve these drugs for severe cases. Molecular examinations identified blaTEM, blaSHV, and blaCTX-M genes in ceftriaxone-resistant strains, while qnrS was specific to ciprofloxacin-resistant variants. Notably, all examined strains exhibited a singular mutation in the gyrA gene, maintaining wild-type gyrB and parC genes. The erm(B) gene emerged as the primary determinant of azithromycin resistance. Furthermore, a distressing increase in resistance genes was observed over three years, with erm(B), blaTEM and qnrS showing significant upward trends. These findings are a clarion call for robust antimicrobial stewardship programs to curtail inappropriate antibiotic use and forestall the burgeoning threat of antibiotic resistance in S. Typhi.

Prevalence of multidrug resistance Salmonella species isolated from clinical specimens at University of Gondar comprehensive specialized hospital Northwest Ethiopia: A retrospective study

BACKGROUND

Multidrug resistance Salmonellosis remains an important public health problem globally. The disease is among the leading causes of morbidity and mortality in developing countries, but there have been limited recent studies about the prevalence, antimicrobial resistance, and multidrug resistance patterns of Salmonella isolates from various clinical specimens.

OBJECTIVE

Aimed to assess the prevalence, antimicrobial resistance, and multidrug resistance patterns of Salmonella isolates from clinical specimens at the University of Gondar Comprehensive Specialised Hospital, northwestern Ethiopia.

METHOD

A retrospective hospital-based cross-sectional study was conducted to determine the prevalence, antimicrobial resistance, and multidrug resistance patterns of isolated from all clinical specimens at the University of Gondar Salmonella Comprehensive Specialised Hospital from June 1st, 2017 to June 3rd, 2022. A total of 26,154 data points were collected using a checklist of records of laboratory registration. Clinical specimens were collected, inoculated, and incubated for about a week with visual inspection for growth and gram staining. The isolates were grown on MacConkey agar and Xylose Lysine Deoxycholate agar. Pure colonies were identified with a conventional biochemical test, and those unidentified at the species level were further identified by the analytical profile index-20E. Then, antimicrobial susceptibility was determined by the Kirby-Bauer disc diffusion technique. The multidrug resistance Salmonella isolates was identified using the criteria set by Magiorakos. Finally, the data was cleaned and checked for completeness and then entered into SPSS version 26 for analysis. Then the results were displayed using tables and figures.

RESULTS

Of the total 26,154 Salmonella suspected clinical samples, 41 (0.16%) Salmonella species were isolated. Most of the Salmonella isolates, 19 (46.3%), were in the age group of less than 18 years, followed by the age group of 19-44 years, 11 (26.8%). In this study, S. enterica subsp. arizonae accounts for the highest 21 (51%), followed by S. paratyphi A 9 (22%). Of the Salmonella isolates, S. typhi were highly resistant to ampicillin (100%), followed by tetracycline and trimethoprim-sulfamethoxazole, each accounting for 83.3%. Furthermore, S. paratyphi A was resistant to ampicillin (100%), tetracycline (88.9%), and chloramphenicol (88.9%). The overall multi-drug resistance prevalence was 22 (53.7%; 95% CI: 39.7-61). Accordingly, S. paratyphi A was 100% multidrug-resistant, followed by S. typhi (66.6%).

CONCLUSION

A low prevalence of Salmonella species was observed in the past six years. Moreover, most S. typhi and S. paratyphi strains in the study area were found to be resistant to routinely recommended antibiotics like ciprofloxacin and ceftriaxone, compared to what was reported earlier. In addition, all isolates of S. paratyphi A and the majority of S. typhi were multidrug resistant. Therefore, health professionals should consider antimicrobial susceptibility tests and use antibiotics with caution for Salmonellosis management.

Prevalence and drug resistance patterns of Gram-negative enteric bacterial pathogens from diarrheic patients in Ethiopia: A systematic review and meta-analysis

Background

Diarrhoea is the leading cause of morbidity and mortality in the world particularly in developing countries and among vulnerable groups of the population. Gram-negative enteric bacterial pathogens (GNEBPs) are a group of organisms that reside mainly in the intestine and induce diarrhoea. Antimicrobial agents are usually the part of their treatment regimen. The therapeutic effect of antimicrobials is hindered by the emergence and spread of drug-resistant strains. The information regarding the prevalence and antimicrobial resistance patterns of GNEBPs in Ethiopia is limited and found in a scattered form.

Objectives

This study was designed to determine the pooled prevalence and drug resistance patterns of GNEBPs by meta-analysis of data from diarrhoeic patients in Ethiopia.

Method

A comprehensive literature search was conducted through internet searches using Google Scholar, PubMed, Science Direct, HINARI databases, and reference lists of previous studies. Published articles were included in the study based on priorly set inclusion and exclusion criteria. Results were presented in the forest plot, tables, and figures with a 95% confidence interval (CI). The inconsistency index (I²) test statistics was used to assess heterogeneity across studies. The pooled prevalence estimate of GNEBPs and their drug resistance patterns were computed by a random-effects model. Software for Statistics and Data Science (STATA) version 14 statistical software was used for the analysis.

Result

After removing those articles which did not fulfil the inclusion criteria, 43 studies were included in the analysis. Studies were conducted in 8 regions of the country and most of the published articles were from the Amhara region (30.23%) followed by Oromia (18.60%) and Southern Nations, Nationalities, and Peoples’ region (SNNP) (18.60%). The pooled prevalence of GNEBPs was 15.81% (CI = 13.33–18.29). The funnel plot indicated the presence of publication bias. The pooled prevalence of GNEBPs in Addis Ababa, Amhara, SNNP, and Oromia regions were 20.08, 16.67, 12.12, and 11.61%, respectively. The pooled prevalence was 14.91, 18.03, and 13.46% among studies conducted from 2006–2010, 2011–2015, and 2016–2021, respectively and it was the highest (20.35%) in children having age less than or equal to 15 years. The pooled prevalence of Escherichia coli, Campylobacter spp., Shigella spp., and Salmonella enterica were 19.79, 10.76, 6.24, and 5.06%, respectively. Large proportions (60–90%) of the isolates were resistant to ampicillin, amoxicillin, tetracycline, and trimethoprim-sulphamethoxazole. The pooled prevalence of multidrug resistance (MDR) was 70.56% (CI = 64.56–76.77%) and MDR in Campylobacter spp., Shigella spp., E. coli, and S. enterica. were 80.78, 79.08, 78.20, and 59.46%, respectively.

Conclusion

The pooled estimate showed a high burden of GNEBPs infections and a high proportion of drug resistance characters to commonly used antimicrobial agents in Ethiopia. Therefore, performing drug susceptibility tests, establishing an antimicrobial surveillance system and confirmation by molecular techniques are needed.

Prevalence and antimicrobial susceptibility level of typhoid fever in Ethiopia: A systematic review and meta-analysis

Typhoid fever continues to be a health challenge in low-and middle-income countries where access to clean water and sanitation infrastructure is scarce. The non-confirmatory diagnostic method continues to hinder effective diagnosis and treatment, ensuring in a high antimicrobial resistance. This systematic review and meta-analysis aimed to estimate the pooled prevalence and antimicrobial susceptibility level of typhoid fever in Ethiopia. The review was designed based on the condition-context-population review approach. Fifteen eligible articles were identified from PubMed, Google Scholar, and Science Direct databases. Risk of bias and quality of studies were assessed using the Joanna Briggs Institute's appraisal criteria. Heterogeneity was assessed using Cochran's Q test and I2 statistics. The review protocol was registered in PROSPERO (registration number CRD42021224478). The estimated pooled prevalence of typhoid fever from blood and stool culture diagnosis was 3% (95% CI: 2%-4%, p < 0.01) (I2  = 82.25) and Widal test examination 33% (95% CI: 22%-44%) (I2  = 99.14). The sub-group analyses identified a lower detection of typhoid fever of 2% (95% CI: 1%-3%) among febrile patients compared to typhoid suspected cases of 6% (95% CI: 2%-9%). The stool culture test identified was twofold higher, value of 4% (95% CI: 2%-7%) salmonella S. Typhi infection than blood culture test of 2% (95% CI: 1%-4%). The antimicrobial susceptibility of salmonella S. Typhi for antibiotics was 94%, 80% and 65% for ceftriaxone, ciprofloxacin, and gentamycin respectively. Low susceptibility of salmonella S. Typhi isolates against nalidixic acid 22% (95% CI: 2%-46%) and chloramphenicol 11% (95% CI: 2%-20%) were observed. The diagnosis of typhoid fever was under or overestimated depending on the diagnostic modality. The Widal test which identified as nonreliable has long been used in Ethiopia for the diagnosis of salmonella S. Typhi causing high diagnosis uncertainties. Antimicrobial susceptibility of salmonella S. Typhi was low for most nationally recommended antibiotics. Ethiopian Food and Drug Authority must strengthen its continued monitoring and enhanced national antimicrobial surveillance system using the best available state-of-the-art technology and or tools to inform the rising resistance of salmonella S. Typhi towards the prescription of standard antibiotics. Finally, it is crucial to develop an evidence-based clinical decision-making support system for the diagnosis, empiric treatment and prevention of antimicrobial resistance.

Descriptive Analysis of Typhoid Fever Surveillance Data in the Jimma Zone, Southwest Ethiopia (2015-2019)

Introduction

Typhoid fever is a major cause of morbidity and mortality around the globe, and it is a serious illness in developing countries. Typhoid fever is prevalent in Ethiopia, and the burden differs with diverse demography, environment, and climate. The study aimed to determine the incidence of typhoid fever cases by person, place, and time.

Method

A descriptive cross-sectional study was conducted among the five years (2015–2019) of surveillance data of typhoid fever in the Jimma Zone, Oromia Region, Ethiopia. The data were extracted from the zonal health management information system database from May to June 2020. SPSS version 21 was used to enter and analyze the data. Descriptive analysis was used to assess the distribution of typhoid fever incidence in time, place, and personal groups.

Result

A total of 36,641 individuals suffered from typhoid fever during the five years. Among these, 18,972 (51.8%) were females and 17,669 (48.2%) were males. Incidence of typhoid fever was found as follows: 216, 198, 203, 264, and 299 cases per 100,000 persons were reported during 2015, 2016, 2017, 2018, and 2019, respectively. Typhoid fever cases were increased by 1.4 from 2015–2019. A high incidence of cases was observed at the start of wet months. The majority of the investigated cases were identified in Kersa, 4,476 (12.2%), Gomma, 4,075 (11.1%), and Mana, 3,267 (8.9%), woredas. Of the total, 151 (0.4%) of the reported cases were admitted for inpatient care. During the five years of surveillance data, death was not reported from all woredas. Conclusion and Recommendation. Typhoid fever was a major public health problem in the Jimma Zone for the last 5 years, and it was increased through the years. Zonal health departments should strengthen the interventions focused on the woredas that had a high burden of typhoid fever at the start of the wet months.

Salmonella Typhi and Salmonella Paratyphi prevalence, antimicrobial susceptibility profile and factors associated with enteric fever infection in Bahir Dar, Ethiopia

Enteric fever (EF) is caused by Salmonella enterica serovars Typhi (S. Typhi) and Paratyphi (S. Paratyphi) causing significant health problems in developing countries including Ethiopia. Thus present study aimed to determine prevalence and antimicrobial resistance profile of S. Typhi and S. Paratyphi among EF suspected patients at Felege-Hiwot comprehensive specialized hospital, Bahir Dar, Ethiopia. Hospital based cross-sectional study was conducted from March-to-May 2020. Totally, 150 patients were included conveniently. Data were collected using questionnaires by face-to-face interview. Concurrently, venous blood and stool specimens were collected and processed following standard bacteriological technique. Antimicrobial susceptibility test (AST) was performed by disc diffusion method. Logistic regression was performed to identify factors associated with EF infection. The study indicated 5.3% EF prevalence where S. Typhi accounted 75%. S. Typhi and S. Paratyphi isolates were 100% sensitive to cephalosporins but at least 83.3% showed resistance against chloramphenicol and tetracycline. At least 66.7% of isolates were multidrug resistance (MDR). Using well water for drinking (AOR = 6.22, CI 1.4-27.5) and previous EF history (AOR = 10.74, CI 2.01-55.9) were significantly associated with EF infection. Thus high bacterial prevalence and MDR isolates was observed. Therefore, health professionals should consider AST and use antibiotics with cautions for EF patient management.

Prevalence of Salmonella enterica serovar Typhi infection, its associated factors and antimicrobial susceptibility patterns among febrile patients at Adare general hospital, Hawassa, southern Ethiopia

BACKGROUND

Salmonellas enterica serovar Typhi (S.typhi) causes typhoid fever and is a global health problem, especially in developing countries like Ethiopia. But there is a little information about prevalence and factors association with S.typhi and its antimicrobial susceptibility pattern in Ethiopia especially in the study area. The aim of this study was to determine the prevalence of S.typhi infection, its associated factors and antimicrobial susceptibility pattern among patient with a febrile illness at Adare General Hospital, Hawassa, Southern Ethiopia.

METHODS

Hospital based cross sectional study was conducted among 422 febrile patients from May 23, 2018 to October 20, 2018. A 5 ml venous blood was collected from each febrile patient. Culture and biochemical test were performed for each isolate. Antimicrobial susceptibility testing was performed for each isolate using modified Kirby-Bauer disk diffusion techniques.

RESULT

In this study, the prevalence of S.typhi among febrile illness patients at Adare General Hospital was 1.6% [95% confidence interval (CI): 0.5-2.9]. The age of the study subjects were ranged from 15 to 65 years (mean age 32 years). It was observed that participants who came from rural area had 8 times (AOR 8.27: 95% CI: 1.33, 51.55) more likely to had S. typhi infection when compared with urban dwellers. The microbial susceptibility testing revealed that all six of S.typhi isolates showed sensitive to Ceftriaxone and all 6 isolates showed resistant to nalidixic acid and Cefotaxime and 5(83.3%) susceptible to Chloramphenicol and Ciprofloxaciline. Multidrug resistance (resistance to three or more antibiotics) was observed among most of the isolates.

CONCLUSION

S. typhi bacteraemia is an uncommon but important cause of febrile illness in our study population. Ceftriaxone therapy is a suitable empirical antibiotic for those that are unwell and suspected of having this illness. Further surveillance is required to monitor possible hanging antibiotic resistant patterns in Ethiopia.

Salmonella Virulence and Immune Escape

Salmonella genus represents the most common foodborne pathogens causing morbidity, mortality, and burden of disease in all regions of the world. The introduction of antimicrobial agents and Salmonella-specific phages has been considered as an effective intervention strategy to reduce Salmonella contamination. However, data from the United States, European countries, and low- and middle-income countries indicate that Salmonella cases are still a commonly encountered cause of bacterial foodborne diseases globally. The control programs have not been successful and even led to the emergence of some multidrug-resistant Salmonella strains. It is known that the host immune system is able to effectively prevent microbial invasion and eliminate microorganisms. However, Salmonella has evolved mechanisms of resisting host physical barriers and inhibiting subsequent activation of immune response through their virulence factors. There has been a high interest in understanding how Salmonella interacts with the host. Therefore, in the present review, we characterize the functions of Salmonella virulence genes and particularly focus on the mechanisms of immune escape in light of evidence from the emerging mainstream literature.