Browse

Journals By Subject

Life Sciences, Agriculture & Food
Chemistry
Medicine & Health
Materials Science
Mathematics & Physics
Electrical & Computer Science
Earth, Energy & Environment
Architecture & Civil Engineering
Education
Economics & Management
Humanities & Social Sciences
Multidisciplinary

Books

Publish Conference Abstract Books
Upcoming Conference Abstract Books
Published Conference Abstract Books
Publish Your Books
Upcoming Books
Published Books

Proceedings

Events

Events
Five Types of Conference Publications

Join

Join as Editorial Board Member
Become a Reviewer

Information

For Authors
For Reviewers
For Editors
For Conference Organizers
For Librarians
Article Processing Charges
Special Issue Guidelines
Editorial Process
Manuscript Transfers
Peer Review at SciencePG
Open Access
Copyright and License
Ethical Guidelines
Submit an Article
Research Article | | Peer-Reviewed

Antimicrobial Resistance Profiles of Salmonella spp. Isolated from Clinical Samples in Niamey, Niger

Alio Mahamadou Fody*,  Chaibou Yaou,  Hadiza Ibrahim Bawa,  Laouali Boubou,  Mohamed Alassane Halawen,  Ramatou Sidikou,  Hassimi Sadou,  Nicolas Barro
Published in International Journal of Microbiology and Biotechnology (Volume 11, Issue 2)
Received: 22 May 2026     Accepted: 8 June 2026     Published: 26 June 2026
Views:       Downloads:
Download PDF
Abstract

Background: Salmonella spp. are leading causes of gastroenteritis and typhoid fever worldwide, with hospital-acquired infections posing significant clinical challenges. The emergence of antibiotic resistance among clinical isolates has been increasingly recognized as a major contributor to treatment failure in affected patients. Objective: This study aimed to determine the prevalence and antimicrobial resistance patterns of Salmonella spp. isolated from clinical specimens at the National Hospital of Niamey, Niger. Method: Stool and blood samples were collected from patients presenting with clinical signs of enteric fever or gastroenteritis. Salmonella spp. was identified via standard microbiological methods, and antimicrobial susceptibility testing was performed via the disk diffusion method on Mueller‒Hinton agar in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. Extended-spectrum beta-lactamase (ESBL) production was confirmed by a double-disk synergy test, which assessed the enhancement of inhibition zones between amoxicillin/clavulanic acid and third-generation cephalosporins. Results: Seventy-seven Salmonella isolates were recovered, yielding an overall prevalence of 2.55%. The majority of the isolates (80.52%) were obtained from children under 5 years of age. High resistance rates were observed against amoxicillin and amoxicillin/clavulanic acid (79% each). Multidrug resistance (resistance to ≥3 antibiotic classes) was detected in 25.97% of the isolates, whereas 35% were resistant to at least two antibiotics. Notably, 5.19% of the isolates were confirmed as ESBL-producing strains. Conclusion: These findings highlight the significant burden of multidrug-resistant Salmonella spp., including ESBL producers, in the clinical setting of Niamey. The high prevalence of resistance to commonly used antibiotics underscores the urgent need for enhanced antimicrobial resistance surveillance, rational antibiotic use, and infection control strategies to curb the spread of resistant strains in healthcare and community environments.

Published in International Journal of Microbiology and Biotechnology (Volume 11, Issue 2)
DOI 10.11648/j.ijmb.20261102.14
Page(s) 76-84
Creative Commons

This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.

Copyright

Copyright © The Author(s), 2026. Published by Science Publishing Group
Previous article
Keywords

Salmonella spp., Clinical Isolates, Antimicrobial Resistance, Multidrug Resistance, Extended-spectrum Beta-lactamases (ESBL), Niger

1. Introduction
Salmonella is a gram-negative enteric bacterium responsible for a significant burden of foodborne illness in both humans and animals worldwide
[1, 2]
. In 2015, according to Shukee et al., the genus encompasses a diverse group of pathogens that collectively account for an estimated 93.8 million annual cases of gastroenteritis worldwide, resulting in approximately 155,000 deaths
[3]
. According to WHO (2018), Salmonella enterica serovars Typhi and Paratyphi are the causative agents of enteric fever, contributing to 11–21 million cases of typhoid fever and 128,000–161,000 associated deaths annually, as well as an estimated 6 million cases of paratyphoid fever, with over 54,000 fatalities
[4]
. In sub-Saharan Africa, nontyphoidal Salmonella infections are a major cause of invasive bacterial disease, contributing to approximately 680,000 deaths each year according to Post et al., in 2029
[5]
.
The emergence and spread of antimicrobial resistance (AMR) in Salmonella spp. represent critical public health challenges. WHO declared 3GC-resistant Enterobacteria & FQ-resistant Salmonella are critical and high group pathogen
[4]
. Resistance to first- and second-line antibiotics compromises the efficacy of clinical treatment, leading to prolonged illness, increased risk of complications, and increased mortality rates
[2]
. In sub-Saharan West Africa, the mortality burden attributable to AMR is particularly high, with estimates reaching 27.3 deaths per 100,000 infections
[6]
. Furthermore, the World Bank projects that AMR could increase healthcare expenditures by up to 25% in low-income countries and by 8% globally
[7]
.
Multidrug-resistant (MDR) Salmonella strains have been increasingly reported during outbreaks, undermining therapeutic options for salmonellosis
[8]
. In Burkina Faso, MDR phenotypes are increasing among Salmonella isolates from pediatric populations
[9]
, whereas in Niger, recent studies have documented the emergence of resistance to third-generation cephalosporins and fluoroquinolone key agents used in the management of invasive salmonellosis and shigellosis, highlighting the need for cautious antibiotic use and continuous surveillance
[10]
.
This study aimed to evaluate the antimicrobial susceptibility profiles of Salmonella spp. isolated from blood and stool samples at the National Hospital of Niamey, Niger. These findings provide critical insights into the current patterns of resistance to antibiotics commonly employed in the treatment of gastroenteritis and enteric fever, informing clinical decision-making and public health interventions in the region.
2. Materials and Methods
2.1. Study Design and Duration
A descriptive cross-sectional study was conducted between July 2017 and May 2018 at the Laboratory of Clinical Biology, National Hospital of Niamey. Stool and blood samples were collected from patients who presented with diarrhea or clinically suspected typhoid fever.
2.2. Sample Collection and Culture Procedures
2.2.1. Stool Samples
Stool samples were collected aseptically in sterile containers. Approximately one gram of each sample was suspended in physiological saline for pre-enrichment. A few drops of the suspension were subsequently inoculated into selenite broth and incubated at 37°C for 10 hours for selective enrichment. Following enrichment, the cultures were streaked onto Hektoen enteric agar and incubated at 37°C for 24 hours for isolation of Salmonella species according to FDA
[11]
.
2.2.2. Blood Samples
Blood samples were collected directly into aerobic blood culture bottles and incubated in the bioMerieux Bact/Alert 3D automated culture system at 37°C for up to 5 days
[12]
. Bottles flagged as positive by the system were subcultured by inoculating 10 μL onto Blood Agar and Hektoen Enteric Agar [or specify appropriate media], followed by incubation at 37°C for 18–24 hours
[12]
.
2.3. Identification of Isolates
Suspected Salmonella colonies were identified by their morphological characteristics on selective media, cultural properties, and standard biochemical tests, including oxidase assays (negative for Salmonella). Presumptive isolates were further confirmed via the API 20E system (bioMerieux), a standardized, miniaturized panel of 20 biochemical tests designed for the identification of Enterobacteriaceae and other gram-negative bacilli
[13]
. Identification was achieved through numerical code generation and comparison with the reference database.
2.4. Antibiotic Susceptibility Testing
Antibiotic susceptibility was assessed via the disk diffusion method on Mueller‒Hinton agar (Liofilchem, Italy) in ac-cordance with the guidelines of the Antibiogram Committee of the French Society for Microbiology (CA-SFM)
[14]
. The tests included antibiotics from three major classes: be-ta-lactams (amoxicillin [20 µg], amoxicillin-clavulanic acid [20 µg + 10 µg], ceftriaxone [30 µg], ceftazidime [10 µg], cefotaxime [5 µg], and imipenem [10 µg]), aminoglycosides (gentamicin [10 µg] and amikacin [30 µg]), and quinolones (nalidixic acid [30 µg] and ciprofloxacin [5 µg]).
Phenotypic detection of extended-spectrum beta-lactamase (ESBL) production was performed via the double-disk synergy test (DDST), with ceftriaxone (30 µg) and cefotaxime (5 µg) disks placed at a distance of 20 mm (edge-to-edge) from an amoxicillin‒clavulanic acid (30 µg) disk, as recommended by the CA-SFM 2017 guidelines
[14]
. A positive result was defined as an increase in the inhibition zone toward the clavulanic acid disk, indicating synergy.
2.5. Ethical Considerations
All isolates were derived from biological specimens collected during routine clinical procedures from patients, with ethical approval granted by the Ethics Committee of the National Hospital of Niamey (Authorization No. 00075/DHNN/DAF/SGRH, dated November 15, 2016). No additional sampling was performed for research purposes.
2.6. Statistical Analysis
The data were entered and analyzed via Microsoft Excel (Microsoft® Office 2019). The chi-square test was used to evaluate associations between categorical variables. A p-value < 0.05 was considered statistically significant.
3. Results
A total of 3,024 clinical specimens, comprising 2,837 stool samples and 187 blood culture samples, were analyzed at the Bacteriology Unit of the National Hospital of Niamey during the study period.
3.1. Prevalence of Salmonella spp. by Sample Type
Overall, 77 Salmonella spp. isolates were identified, resulting in a total prevalence of 2.55% (95% CI: 2.02–3.17%). The distribution of Salmonella isolates by specimen type is summarized in Table 1.
Among the stool samples, 67 out of 2,837 tested positive for Salmonella spp., yielding a prevalence of 2.22% (95% CI: 1.73–2.81%). Among the blood cultures, 10 out of the 187 samples were positive, corresponding to a prevalence of 5.35% (95% CI: 2.68–9.42%). This difference in prevalence between stool and blood samples was statistically significant (χ² = 13.78, p < 0.001), indicating that a greater proportion of Salmonella was detected in blood cultures despite the smaller sample size.
Table 1. Prevalence of Salmonella spp. by sample type.

Sample types

Sample numbers

Salmonella spp. prevalence% (n)

Stool samples

2,837

2.22 (60)

Blood samples

187

5.35 (10)

Total

3,024

2.55 (77)
3.2. Prevalence of Salmonella spp. Strains According to Sociodemographic Characteristics
The prevalence of Salmonella spp. was 53.24% (n = 41) among male patients and 46.76% (n = 36) among female patients. Statistical analysis revealed no significant difference in the prevalence of Salmonella between the sexes (p = 0.5485).
Salmonellosis affects individuals across all age groups; however, a marked variation in prevalence was observed according to age (Figure 1). The highest prevalence was recorded in children aged 0–5 years, with 80.52% (n = 62) of the cases. In contrast, the prevalence was substantially lower in the older age groups: 3.90% (n = 3) in the 6–18 years group, 7.79% (n = 6) in the 19–25 years group, 2.60% (n = 2) in the 26–45 years group, and 5.19% (n = 4) in the 46–60 years group. This age-related difference in Salmonella spp. prevalence was statistically significant (p < 0.0001).
Figure 1. Prevalence of Salmonella spp. by age (years).
3.3. Prevalence of Salmonella spp. Isolates by Sample Origin
Analysis of the data presented in Table 2 revealed a Salmonella spp. prevalence of 40.26% among outpatients, which was significantly higher (p < 0.0001) than that among inpatients across hospitalization departments. Among inpatient clinics, the highest prevalence was observed in the pediatric referral clinic (31.17%), followed by the Pediatrics A clinic (23.38%). Lower prevalence rates were recorded in the Medicine B clinic (3.90%) and the Pediatrics B clinic (1.30%). A statistically significant variation in Salmonella spp. prevalence was also observed across different hospitalization departments (p < 0.0001).
Table 2. Prevalence of Salmonella spp. isolates according to sample origin.

Samples origin

Salmonella spp. prevalence% (n)

Pediatrics A office

23.38 (18)

Pediatrics B office

1.30 (1)

Pediatric referral office

31.17 (24)

Medicine B office

3.90 (3)

External

40.26 (31)
3.4. Antibiotic Susceptibility of Salmonella spp. Isolates
Analysis of Salmonella spp. Isolates obtained from blood cultures (Figure 2) revealed high resistance rates within the beta-lactam antibiotic class: 90% of the isolates were resistant to both amoxicillin and amoxicillin/clavulanic acid. In contrast, susceptibility to third-generation cephalosporins was high, with 90% of the isolates showing sensitivity to ceftazidime, cefotaxime, and ceftriaxone. All the isolates were fully susceptible (100% sensitivity) to the carbapenem imipenem. Among the 10 antibiotics tested, only a single isolate exhibited multidrug resistance, defined as resistance to eight antimicrobial agents.
With respect to aminoglycosides, 90% of the isolates were susceptible to gentamicin, whereas 100% were susceptible to amikacin. Within the quinolone class, both nalidixic acid and ciprofloxacin demonstrated 90% susceptibility rates.
These findings highlight a high level of resistance to certain beta-lactams but preserved susceptibility to extended-spectrum cephalosporins, carbapenems, aminoglycosides, and fluoroquinolones among the majority of Salmonella spp. Isolates.
Figure 2. Antibiotic susceptibility of Salmonella spp. Isolated from blood samples.
Analysis of stool-derived bacterial isolates (Figure 3) revealed antimicrobial susceptibility patterns across key antibiotic classes. Among β-lactam agents, amoxicillin and amoxicillin-clavulanate (augmentin) have low susceptibility rates, with a reported sensitivity of 31%. In contrast, extended-spectrum cephalosporins and carbapenems demonstrated greater efficacy: ceftazidime had 60% sensitivity, cefotaxime had 67%, ceftriaxone had 70%, and imipenem had a markedly high sensitivity rate of 99%.
Within the aminoglycoside class, the susceptibility rates were 64% for gentamicin and 94% for amikacin, indicating the superior activity of the latter. Specifically, among Salmonella spp. Isolates, susceptibility to nalidixic acid was 73%, whereas 75% of isolates were susceptible to amikacin.
These findings highlight high resistance to penicillins, variable sensitivity to cephalosporins, and preserved susceptibility to carbapenems and amikacin, suggesting that these agents may remain effective therapeutic options in the management of infections caused by these enteric pathogens.
Figure 3. Antibiotic susceptibility of Salmonella spp. Isolated from stool samples.
3.5. Prevalence of Multidrug-resistant Salmonella spp. Strains
Analysis of the data presented in Table 3 revealed that 20.78% of the Salmonella spp. isolates were susceptible to all antibiotics tested in this study. In contrast, only a single isolate (1.30%), obtained from a stool sample, exhibited resistance to all the tested antimicrobial agents. Resistance to nine, eight, seven, six, and five antibiotics was observed in 2.60%, 12.99%, 3.90%, 3.90%, and 1.30% of the isolates, respectively. Notably, a substantial proportion of the isolates (35.06%) displayed resistance to two antibiotics, indicating a high prevalence of multidrug resistance among the Salmonella strains analyzed.
Table 3. Prevalence of multidrug-resistant Salmonella spp.

Number of resistant antibiotics

Resistance of Salmonella spp% (n)

10

1.30 (1)

9

2.60 (2)

8

12.99 (10)

7

3.90 (3)

6

3.90 (3)

5

1.30 (1)

4

2.60 (2)

3

9.09 (7)

2

35.06 (27)

1

6.49 (5)
3.6. Prevalence of Extended-spectrum Beta-lactamase (ESBL)-producing Salmonella spp.
An analysis of the data in Table 4 revealed that 20 Salmonella spp. isolates were resistant to at least five antibiotics, resulting in a multidrug resistance prevalence of 25.97%. Among these multidrug-resistant isolates, four were identified as extended-spectrum beta-lactamase (ESBL) producers and were isolated from stool samples. This corresponds to an overall prevalence of 5.19% for ESBL-producing Salmonella spp. (Table 4).
Table 4. Prevalence of ESBL-producing Salmonella spp.

Samples types

MDR Salmonella spp.

Salmonella spp. ESBL

Stool samples

24.67% (19)

5.19% (4)

Blood samples

1.30% (1)

0.00% (0)

Total

25.97% (20)

5.19% (4)
4. Discussion
Salmonella infections represent a significant public health burden in Africa, particularly among poor urban populations, where they contribute to a disproportionate number of deaths
[15]
. This burden is exacerbated in low-income countries because of inadequate control measures and limited adherence to proper food safety practices
[16]
.
In this study, the prevalence of Salmonella spp. in clinical stool samples was 2.22%. This finding is comparable to reports from Burkina Faso (3.07%) and Nepal (3.1%) (p = 0.6547)
[17, 18]
. However, it is significantly lower than the prevalence reported in other studies conducted in Burkina Faso (9.50%), Tanzania (16.5%), and Iraq (14.8%) (p = 0.0068)
[9, 19, 20]
. These discrepancies may be attributed to differences in study design, sample size, population characteristics, and regional variations in hygiene, sanitation, and access to healthcare.
Notably, a low prevalence of 0.33% was observed in the blood culture samples. This result is significantly lower (p < 0.0001) than those reported in studies from Kenya (3.54%), the Democratic Republic of the Congo (41.66%), Nigeria (7.27%), and Nepal (3.10%)
[15, 21-23]
. The low bacteremia rate in our study may be partly explained by the relatively short duration of the study period and the limited sample size, which could affect the detection of bloodstream infections. The observed disparity suggests a greater clinical severity associated with bacteremia Salmonella infections in this population, although the lower number of blood samples limits direct comparison. These findings highlight the importance of blood culture surveillance in the diagnosis of invasive salmonellosis.
With respect to sex distribution, Salmonella spp. was more frequently isolated from male patients (53.24%) than from female patients (46.76%). This observation aligns with findings from studies in Mali
[25]
and Tanzania
[26]
. The higher prevalence among males may be associated with behavioural and socioeconomic factors, such as a greater frequency of eating outside the home, potentially increasing exposure to contaminated food or water sources.
Children aged 0–5 years presented the highest prevalence of Salmonella spp. infection (80.52%). This finding is consistent with data from Iran, where a high incidence was reported in children under 4 years of age
[27]
, and from Bangladesh, where 62% of typhoid fever cases were attributed to Salmonella spp.
[28]
. The heightened susceptibility of young children may be linked to widespread malnutrition in resource-limited settings, which can compromise intestinal immunity and alter the gut microbiota, thereby increasing vulnerability to enteric pathogens
[29]
.
Antimicrobial susceptibility testing revealed high levels of resistance to amoxicillin and amoxicillin/clavulanic acid. These findings are consistent with a study in Nigeria, which reported 100% resistance to amoxicillin/clavulanic acid
[22]
. In contrast, studies in Nepal and Kathmandu demonstrated high sensitivity (100% and 91%, respectively) to amoxicillin
[18, 23]
. The observed variation in resistance patterns may reflect differences in antibiotic usage practices, including widespread self-medication for symptoms such as fever, diarrhea, and respiratory infections, as well as the empirical prescription of antibiotics without microbiological confirmation or susceptibility testing
[28]
.
Resistance to third-generation cephalosporins ceftazidime, cefotaxime, and ceftriaxone was low in our isolates. These results are in agreement with previous reports from Nepal
[18]
and Niger
[10]
. However, a study in Nigeria reported 100% resistance to ceftazidime and cefotaxime
[22]
, which may be attributed to prior antibiotic exposure, as the isolates in that study were obtained from patients already experiencing febrile illness, likely after self-treatment.
Our isolates showed high susceptibility to amikacin (97%) and imipenem (99%), indicating that these agents remain effective therapeutic options for severe salmonellosis. A study in Cameroon reported 90% susceptibility to imipenem
[24]
; the slightly lower sensitivity may reflect greater -carbapenem use in that setting, potentially driving selective pressure.
Multidrug resistance (MDR), defined as resistance to two or more antibiotic classes, was observed in 35% of Salmonella spp. isolates. This is lower than the 85% MDR prevalence reported in a Bangladeshi study based on blood isolates
[28]
, a difference that may be influenced by variations in sample size and patient population. Notably, 13% of the isolates in our study exhibited resistance to at least eight different antibiotics, meeting the criteria for extensive drug resistance. This finding is concerning and aligns with reports from South Africa, Ethiopia and Canada, where 22% of isolates were resistant to three or more antibiotics, 31% to five antibiotics, and 59% to three different antibiotic classes
[30-32]
. These data underscore a growing trend of increasing antimicrobial resistance among clinical Salmonella strains.
Among the MDR isolates, 4 (5.19%) were confirmed as extended-spectrum beta-lactamase (ESBL)-producing strains. This prevalence is comparable to reports from Canada (2%) and Thailand (5.1%)
[32, 33]
but lower than rates reported in Nigeria (40.7%) and Qatar (10%) among patients with confirmed typhoid fever
[34, 35]
. The higher ESBL rates in the latter studies may reflect the clinical context—specifically, that isolates were obtained from patients with established enteric fever who had likely received prior antimicrobial treatment, thereby selecting for resistant strains.
In conclusion, our findings highlight the persistent burden of Salmonella infections, particularly among young children and males, and underscore the growing challenge of antimicrobial resistance. Continued surveillance, improved diagnostic practices, rational antibiotic use, and public health interventions targeting food and water safety are essential to mitigate the impact of Salmonella infections in low-resource settings.
5. Conclusion
This study, which was conducted over 10 months at the National Hospital of Niamey, allowed the isolation and identification of Salmonella spp. strains from clinical stool and blood samples. The results revealed a greater prevalence of Salmonella spp. in stool samples than in blood samples. Most of the isolated Salmonella strains were sensitive to the majority of the tested antibiotics, but some showed resistance to certain drugs. Multiple drug-resistant Salmonella strains have been identified, including some that produce extended-spectrum beta-lactamases (ESBLs). Therefore, it is essential to establish a national surveillance system as soon as possible for ESBL-producing Salmonella strains to help prevent their spread.
Abbreviations

AMR

Antimicrobial Resistance

MDR

Multidrug Resistance

ESBL

Extended-Spectrum Beta-Lactamase

CLSI

Clinical and Laboratory Standards Institute

CA-SFM

Antibiogram Committee of the French Society for Microbiology

DDST

Double-Disk Synergy Test

API 20E

Analytical Profile Index 20 Enterobacteriaceae

SFM

French Society for Microbiology

EUCAST

European Committee on Antimicrobial Susceptibility Testing

LaBESTA

Laboratory of Molecular Biology, Epidemiology and Surveillance of Foodborne Bacteria and Viruses

NNH

Niamey National Hospital

GRH

General Reference Hospital
Acknowledgments
We gratefully acknowledge the entire laboratory team from the Biochemistry and Biology Department at the National Hospital of Niamey, particularly the Bacteriology Unit of the Biology Laboratory, for their technical support and valuable contributions to this study. We also extend our sincere gratitude to Boubou Laouali for his dedicated time and assistance.
Author Contributions
Alio Mahamadou Fody: Conceptualization, Methodology, Writing – original draft, Writing – review & editing
Chaibou Yaou: Writing – review & editing
Hadiza Ibrahim Bawa: Writing – review & editing
Laouali Boubou: Data curation, Supervision
Mohamed Alassane Halawen: Writing – review & editing
Ramatou Sidikou: Visualization
Hassimi Sadou: Visualization
Nicolas Barro: Visualization
Data Availability Statement
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.
Conflicts of Interest
The authors have not declared any conflicts of interest.
References
[1] Ghoddusi, A., Nayeri Fasaei, B., Zahraei Salehi, T., & Akbarein, H. Serotype distribution and antimicrobial resistance of Salmonella isolate in human, chicken, and cattle in Iran. Archives of Razi Institute, 2019; 74(3), 259–266.

https://doi.org/10.22092/ari.2018.122351

[2] Chaudhari, R., Singh, K., & Kodgire, P. Biochemical and molecular mechanisms of antibiotic resistance in Salmonella spp. Research in Microbiology, 2023; 174(1–2), 103985.

https://doi.org/10.1016/j.resmic.2022.103985

[3] Shu-kee, E., Priyia, P., Nurul-Syakima, A. B. M., Hooi-leng, S., Kok-Gang, C., & Learn-Han, L. Salmonella: A review on pathogenesis, epidemiology and antibiotic resistance. Frontiers in Life Science, 2015; 8(3), 284–293.
[4] WHO (World Health Organization). Typhoid fever and other invasive salmonellosis. WHO Surveillance Standards, 2018.

https://www.who.int/docs/default-source

[5] Post, A. S., Diallo, S. N., Guiraud, I., Lompo, P., Tahita, M. C., Maltha, J., & Jacobs, J. Supporting evidence for a human reservoir of invasive non-Typhoidal Salmonella from household samples in Burkina Faso. PLoS Neglected Tropical Diseases, 2019; 13(10), e0007782.

https://doi.org/10.1371/journal.pntd.0007782

[6] Murray, C. J., Ikuta, K. S., Sharara, F., Swetschinski, L., Aguilar, G. R., Gray, A., & Tasak, N. Global burden of bacterial antimicrobial resistance in 2019: a systematic analysis. The Lancet, 2022; 399(10325), 629–655.

https://doi.org/10.1016/S0140-6736(21)02724-0

[7] WHO, FAO, OIE, UN. Antimicrobial Resistance and the United Nations Sustainable Development Cooperation Framework. Geneva: WHO, 2021.

https://apps.who.int/iris/handle/10665/346794

[8] Bonilla-Caballero, M. A., Lozano-Puentes, M. P., Ospina, M. A., & Varón-López, M. First report of multidrug-resistant Salmonella Infantis in broiler litter in Tolima, Colombia. Veterinary World, 2022; 15(6), 1557–1562.

https://doi.org/10.14202/vetworld.2022.1557-1562

[9] Konaté, A., Guessennd, N. K., Kouadio, F. K., Dembélé, R., Kagambèga, A., et al. Epidemiology and Resistance Phenotypes of Salmonella spp. Strains Responsible for Gastroenteritis in Children Less Than Five Years of Age in Ouagadougou, Burkina Faso. Archives of Clinical Microbiology, 2019; 10(2), 90.

https://doi.org/10.4172/1989-8756.1000090

[10] Illa, M., Diallo, B. A., Sani, O., Bassira, I., Abdoulaye, O., & Eric, A. Antibiotic resistance of Salmonella and Shigella, isolated from diarrheal children under five years old at the national hospital of Niamey (Niger). European Journal of Pharmaceutical and Medical Research, 2022; 9(8), 558–564.
[11] Food and Drug Administration. (2007). Salmonella (Chapter 5). In Bacteriological analytical manual.

https://www.fda.gov/food/laboratory-methods-food/bam-chapter-5-salmonella

[12] Clinical and Laboratory Standards Institute. Principles and Procedures for Blood Cultures; Approved Guideline. CLSI document M47-A. Wayne, PA: Clinical and Laboratory Standards Institute; 2007.

https://clsi.org/standards/products/microbiology/documents/m47/

[13] Biomerieux. (n.d.). API 20E instructions for use (REF 20100). Marcy-l'Étoile, France: biomerieux SA. Accessed on

https://www.biomerieux.com

[14] Antibiogram Committee of the French Society for Microbiology (CA-SFM/EUCAST). Recommandations V1.0 Mars 2017. Paris: SFM, 2017.

www.sfm-microbiologie.org

[15] Kariuki, S., Mbae, C., Onsare, R., Kavai, S. M., Wairimu, C., Ngetich, R., & Dougan, G. Multidrug-resistant nontyphoidal Salmonella hotspots as targets for vaccine use in management of infections in endemic settings. Clinical Infectious Diseases, 2019; 68(Suppl 1), S10–S16.

https://doi.org/10.1093/cid/ciy954

[16] Bouda, S. C., Kagambega, A., Bonifait, L., Le Gall, F., Ibrahim, H. B., Bako, E., & Barro, N. Prevalence and Antimicrobial Resistance of Salmonella enterica Isolated from Chicken and Guinea Fowl in Burkina Faso. International Journal of Microbiology and Biotechnology, 2019; 4(3), 64–71.

https://doi.org/10.11648/j.ijmb.20190403.12

[17] Dembele R., Konate, A., Soulama, I., Kagambèga, A., Kabore, W. A. D., &Cisse, H. Prevalence of Multidrug-resistant Salmonella enterica and associated factors among under five children with diarrhea in rural Burkina Faso. Clinical and Biotechnology Microbiology, 2018; 3(1), 566–576.
[18] Maharjan, A., Dhungel, B., Bastola, A., Thapa Shrestha, U., Adhikari, N., Banjara, M. R., & Rijal, K. R. Antimicrobial susceptibility pattern of Salmonella spp. isolated from enteric fever patients in Nepal. Infectious Disease Reports, 2021; 13(2), 388–400.

https://doi.org/10.3390/idr13020036

[19] Ngogo, F. A., Abade, A. M., Rumisha, S. F., Mizinduko, M. M., & Majigo, M. V. Factors associated with Salmonella infection in patients with gastrointestinal complaints seeking health care at Regional Hospital in Southern Highland of Tanzania. BMC Infectious Diseases, 2020; 20(1), 1–8.

https://doi.org/10.1186/s12879-020-05190-0

[20] Harb, A., Abraham, S., Rusdi, B., Laird, T., O’dea, M., & Habib, I. Molecular detection and epidemiological features of selected bacterial, viral, and parasitic enteropathogens in stool specimens from children with acute diarrhea in Thi-Qar Governorate, Iraq. International Journal of Environmental Research and Public Health, 2019; 16(9), 1573.

https://doi.org/10.3390/ijerph16091573

[21] Kashosi, T. M., Muhandule, A. B., Mwenebitu, D. L., Mihuhi, N., Mutendela, J. K., & Mubagwa, K. Antimicrobial resistance of Salmonella spp. strains isolated from blood cultures in Bukavu, DR Congo. Pan African Medical Journal, 2018; 29(1), 1–8.

https://doi.org/10.11604/pamj.2018.29.1.13087

[22] Akinkunmi, F., Ajoseh, S., Fakorede, C., Abegunrin, R., Salami, W., Lawal, A., & Akinyemi, K. Prevalence of Salmonella blood-stream infection and antimicrobial resistance in Lagos, Nigeria. Infection Epidemiology and Microbiology, 2023; 9(1), 0-0.
[23] Bastola, A., Pyakurel, P., Rayamajhi, R. B., Shrestha, S., Thekkur, P., Pandey, B., & Edwards, J. K. High Resistance of Salmonella spp. In addition, Shigella spp. in Blood and Stool Cultures from the Sukraraj Tropical and Infectious Disease Hospital, Kathmandu, Nepal, 2015–2019. Tropical Medicine and Infectious Disease, 2021; 6(2), 59.

https://doi.org/10.3390/tropicalmed6020059

[24] Ndip, R., Awah, L., Ghogomu, S., Cho-Ngwa, F., & Ngemenya, M. Isolation and molecular identification of Salmonella with high multidrug resistance to first line typhoid antibiotics in Southwest Cameroon. Microbes and Infectious Diseases, 2022; 3(4), 988–997.

https://doi.org/10.1016/j.micinf.2022.07.003

[25] Diarra, B., Guindo, I., Koné, B., Dembélé, M., Cissé, I., Thiam, S., & Djimde, A. High frequency of antimicrobial resistance in Salmonella and Escherichia coli causing diarrheal diseases at the Yirimadio community health facility, Mali. BMC Microbiology, 2024; 24(1), 35.

https://doi.org/10.1186/s12866-024-03199-8

[26] Hugho, E. A., Kumburu, H. H., Thomas, K., Lukambagire, A. S., Wadugu, B., Amani, N., & Mmbaga, B. T. High diversity of Salmonella spp. from children with diarrhea, food, and environmental sources in Kilimanjaro–Tanzania: one health approach. Frontiers in Microbiology, 2024; 14, 1277019.

https://doi.org/10.3389/fmicb2023.1277019

[27] Abbasi, E., & Ghaznavi-Rad, E. Quinolone resistant Salmonella species isolated from pediatric patients with diarrhea in central Iran. BMC Gastroenterology, 2021; 21, 1–6.

https://doi.org/10.1186/s12876-021-01700-3

[28] Mina, S. A., Hasan, M. Z., Hossain, A. Z., Barua, A., Mirjada, M. R., & Chowdhury, A. M. A. The prevalence of multidrug-resistant Salmonella typhi isolated from blood sample. Microbiology Insights, 2023; 16, 11786361221150760.

https://doi.org/10.1177/11786361221150760

[29] Zaki, S. A., & Karande, S. Multidrug-resistant typhoid fever: a review. Journal of Infection in Developing Countries, 2011; 5(5), 324–337.

https://doi.org/10.3855/jidc.1555

[30] Ramatla, T., Khasapane, N. G., Mlangeni, L. N., Mokgokong, P., Ramaili, T., Ndou, R., & Thekisoe, O. Detection of Salmonella Pathogenicity Islands and Antimicrobial Resistance Genes in Salmonella enterica Serovars Enteritidis and Typhimurium Isolated from Broiler Chickens. Antibiotics, 2024; 13(5), 458.

https://doi.org/10.3390/antibiotics13050458

[31] Amare, A., Eshetie, S., Kasew, D., Amare, A., Abebe, W., & Moges, F. Prevalence of Salmonella spp., Shigella spp., and intestinal parasites among food handlers working in University of Gondar student’s cafeteria, Northwest Ethiopia. Frontiers in Public Health, 2024; 12.

https://doi.org/10.3389/fpubh.2024.1370338

[32] Primeau, C. A., Bharat, A., Janecko, N., Carson, C. A., Mulvey, M., Reid-Smith, R., & Parmley, E. J. Integrated surveillance of extended-spectrum beta-lactamase (ESBL)-producing Salmonella and Escherichia coli from humans and animal species raised for human consumption in Canada from 2012 to 2017. Epidemiology and Infection, 2023; 151, e14.

https://doi.org/10.1017/S0950268822001847

[33] Saechue, B., Atwill, E. R., & Jeamsripong, S. Occurrence and molecular characteristics of antimicrobial resistance, virulence factors, and extended-spectrum β-lactamase (ESBL) producing Salmonella enterica and Escherichia coli isolated from the retail produce commodities in Bangkok, Thailand. Heliyon, 2024; 10(5), e29345.

https://doi.org/10.1016/j.heliyon.2024.e29345

[34] Akinyemi, K. O., Al-Khafaji, N. S., Al-Alaq, F. T., Fakorede, C. O., Al-Dahmoshi, H. O., Iwalokun, B. A., & Saki, M. Extended-spectrum beta-lactamases encoding genes among Salmonella enterica serovar Typhi isolates in patients with typhoid fever from four academic medical centers in Lagos, Nigeria. Revista de Investigación Clínica, 2022; 74(3), 165–171.

https://doi.org/10.21814/ric.2022.359

[35] Goravey, W., Tsui, C. K., Ali, G. A., Najim, M. S., Shunnar, K., Ibrahim, E. B., & Hadi, H. A. Clinical, phenotypic, and genotypic characteristics of ESBL-producing Salmonella enterica bloodstream infections from Qatar. IJID Regions, 2024; 11, 100368.

https://doi.org/10.1016/j.ijregi.2024.100368

Cite This Article
Plain Text BibTeX RIS

  • APA Style

    Fody, A. M., Yaou, C., Bawa, H. I., Boubou, L., Halawen, M. A., et al. (2026). Antimicrobial Resistance Profiles of Salmonella spp. Isolated from Clinical Samples in Niamey, Niger. International Journal of Microbiology and Biotechnology, 11(2), 76-84. https://doi.org/10.11648/j.ijmb.20261102.14

    Copy | Download

    ACS Style

    Fody, A. M.; Yaou, C.; Bawa, H. I.; Boubou, L.; Halawen, M. A., et al. Antimicrobial Resistance Profiles of Salmonella spp. Isolated from Clinical Samples in Niamey, Niger. Int. J. Microbiol. Biotechnol. 2026, 11(2), 76-84. doi: 10.11648/j.ijmb.20261102.14

    Copy | Download

    AMA Style

    Fody AM, Yaou C, Bawa HI, Boubou L, Halawen MA, et al. Antimicrobial Resistance Profiles of Salmonella spp. Isolated from Clinical Samples in Niamey, Niger. Int J Microbiol Biotechnol. 2026;11(2):76-84. doi: 10.11648/j.ijmb.20261102.14

    Copy | Download 

  • @article{10.11648/j.ijmb.20261102.14,
  author = {Alio Mahamadou Fody and Chaibou Yaou and Hadiza Ibrahim Bawa and Laouali Boubou and Mohamed Alassane Halawen and Ramatou Sidikou and Hassimi Sadou and Nicolas Barro},
  title = {Antimicrobial Resistance Profiles of Salmonella spp. Isolated from Clinical Samples in Niamey, Niger},
  journal = {International Journal of Microbiology and Biotechnology},
  volume = {11},
  number = {2},
  pages = {76-84},
  doi = {10.11648/j.ijmb.20261102.14},
  url = {https://doi.org/10.11648/j.ijmb.20261102.14},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.ijmb.20261102.14},
  abstract = {Background: Salmonella spp. are leading causes of gastroenteritis and typhoid fever worldwide, with hospital-acquired infections posing significant clinical challenges. The emergence of antibiotic resistance among clinical isolates has been increasingly recognized as a major contributor to treatment failure in affected patients. Objective: This study aimed to determine the prevalence and antimicrobial resistance patterns of Salmonella spp. isolated from clinical specimens at the National Hospital of Niamey, Niger. Method: Stool and blood samples were collected from patients presenting with clinical signs of enteric fever or gastroenteritis. Salmonella spp. was identified via standard microbiological methods, and antimicrobial susceptibility testing was performed via the disk diffusion method on Mueller‒Hinton agar in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. Extended-spectrum beta-lactamase (ESBL) production was confirmed by a double-disk synergy test, which assessed the enhancement of inhibition zones between amoxicillin/clavulanic acid and third-generation cephalosporins. Results: Seventy-seven Salmonella isolates were recovered, yielding an overall prevalence of 2.55%. The majority of the isolates (80.52%) were obtained from children under 5 years of age. High resistance rates were observed against amoxicillin and amoxicillin/clavulanic acid (79% each). Multidrug resistance (resistance to ≥3 antibiotic classes) was detected in 25.97% of the isolates, whereas 35% were resistant to at least two antibiotics. Notably, 5.19% of the isolates were confirmed as ESBL-producing strains. Conclusion: These findings highlight the significant burden of multidrug-resistant Salmonella spp., including ESBL producers, in the clinical setting of Niamey. The high prevalence of resistance to commonly used antibiotics underscores the urgent need for enhanced antimicrobial resistance surveillance, rational antibiotic use, and infection control strategies to curb the spread of resistant strains in healthcare and community environments.},
 year = {2026}
}

    Copy | Download 

  • TY  - JOUR
T1  - Antimicrobial Resistance Profiles of Salmonella spp. Isolated from Clinical Samples in Niamey, Niger
AU  - Alio Mahamadou Fody
AU  - Chaibou Yaou
AU  - Hadiza Ibrahim Bawa
AU  - Laouali Boubou
AU  - Mohamed Alassane Halawen
AU  - Ramatou Sidikou
AU  - Hassimi Sadou
AU  - Nicolas Barro
Y1  - 2026/06/26
PY  - 2026
N1  - https://doi.org/10.11648/j.ijmb.20261102.14
DO  - 10.11648/j.ijmb.20261102.14
T2  - International Journal of Microbiology and Biotechnology
JF  - International Journal of Microbiology and Biotechnology
JO  - International Journal of Microbiology and Biotechnology
SP  - 76
EP  - 84
PB  - Science Publishing Group
SN  - 2578-9686
UR  - https://doi.org/10.11648/j.ijmb.20261102.14
AB  - Background: Salmonella spp. are leading causes of gastroenteritis and typhoid fever worldwide, with hospital-acquired infections posing significant clinical challenges. The emergence of antibiotic resistance among clinical isolates has been increasingly recognized as a major contributor to treatment failure in affected patients. Objective: This study aimed to determine the prevalence and antimicrobial resistance patterns of Salmonella spp. isolated from clinical specimens at the National Hospital of Niamey, Niger. Method: Stool and blood samples were collected from patients presenting with clinical signs of enteric fever or gastroenteritis. Salmonella spp. was identified via standard microbiological methods, and antimicrobial susceptibility testing was performed via the disk diffusion method on Mueller‒Hinton agar in accordance with Clinical and Laboratory Standards Institute (CLSI) guidelines. Extended-spectrum beta-lactamase (ESBL) production was confirmed by a double-disk synergy test, which assessed the enhancement of inhibition zones between amoxicillin/clavulanic acid and third-generation cephalosporins. Results: Seventy-seven Salmonella isolates were recovered, yielding an overall prevalence of 2.55%. The majority of the isolates (80.52%) were obtained from children under 5 years of age. High resistance rates were observed against amoxicillin and amoxicillin/clavulanic acid (79% each). Multidrug resistance (resistance to ≥3 antibiotic classes) was detected in 25.97% of the isolates, whereas 35% were resistant to at least two antibiotics. Notably, 5.19% of the isolates were confirmed as ESBL-producing strains. Conclusion: These findings highlight the significant burden of multidrug-resistant Salmonella spp., including ESBL producers, in the clinical setting of Niamey. The high prevalence of resistance to commonly used antibiotics underscores the urgent need for enhanced antimicrobial resistance surveillance, rational antibiotic use, and infection control strategies to curb the spread of resistant strains in healthcare and community environments.
VL  - 11
IS  - 2
ER  -

    Copy | Download

Author Information
Download PDF
Submit an Article
  • Abstract
  • Keywords

  • Document Sections

    1. 1. Introduction
    2. 2. Materials and Methods
    3. 3. Results
    4. 4. Discussion
    5. 5. Conclusion
    Show Full Outline
  • Abbreviations
  • Acknowledgments
  • Author Contributions
  • Data Availability Statement
  • Conflicts of Interest
  • References
  • Cite This Article
  • Author Information

About Us

Science Publishing Group (SciencePG) is an Open Access publisher, with more than 300 online, peer-reviewed journals covering a wide range of academic disciplines.

Learn More About SciencePG

Products

Information

Important Link

Copyright © 2012 -- 2026 Science Publishing Group – All rights reserved.