Agnes Kilonzo-Nthenge

Dr. Agnes Kilonzo-Nthenge

Tennessee State University

Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 August 2012 in Journal of Food Protection
Verified
Journal Article
Closed access
AKAgnes Kilonzo-Nthenge
Agnes Kilonzo-Nthenge
ERE. Rotich
E. Rotich
SGS. Godwin
S. Godwin
SNS. Nahashon
S. Nahashon
FCF. Chen
F. Chen
Cronobacter sakazakii is an emerging opportunistic pathogen that has been implicated in cases of severe meningitis, sepsis, and necrotizing enterocolitis in premature and full-term infants. In this study, the prevalence of C. sakazakii was estimated in selected domestic kitchens in middle Tennessee. Antimicrobial resistance patterns of these C. sakazakii isolates were examined for points of public health significance. A total of 234 contact sites in 78 domestic kitchens were tested for C. sakazakii. Consumers' used dishcloths and cleaning sponges were also tested. Antimicrobial susceptibility of the identified C. sakazakii isolates was determined for 10 antimicrobial drugs by means of the disk diffusion method. C. sakazakii was recovered from 26.9% of domestic kitchens visited. Multidrug resistance was observed; the highest resistance was to penicillin (76.1% of isolates) followed by tetracycline (66.6%), ciprofloxacin (57.1%), and nalidixic acid (47.6%). None of the C. sakazakii isolates were resistant to gentamicin. These results suggest that antibiotic-resistant C. sakazakii could be present at various sites in domestic kitchens.

1 March 2008 in Journal of Food Protection
Verified
Journal Article
Closed access
AKAgnes Kilonzo-Nthenge
Agnes Kilonzo-Nthenge
FCFur-Chi Chen
Fur-Chi Chen
SGSandria L. Godwin
Sandria L. Godwin
Consumers' refrigeration practices have a significant impact on the safety and quality of foods. To determine the prevalence and the identity of microorganisms in domestic refrigerators, swab sampl...

1 March 2007 in Journal of Food Protection
Verified
Journal Article
Closed access
AKAgnes Kilonzo-Nthenge
Agnes Kilonzo-Nthenge
JWJean S. Weese
Jean S. Weese
MCMelvin Carter
Melvin Carter
CWCheng-I Wei
Cheng-I Wei
THTung-Shi Huang
Tung-Shi Huang
Interaction of Escherichia coli O157:H7/pGFP with hydroponically grown lettuce plants was evaluated in this study. Lettuce seedlings were planted in contaminated Hoagland's nutrient solution and th...

20 February 2023 in Antibiotics
Verified
Journal Article
Open access
PDF file
WMWinne Mukuna
Winne Mukuna
TATobenna Celestine Aniume
Tobenna Celestine Aniume
BPBharat Pokharel
Bharat Pokharel
CKCollins Khwatenge
Collins Khwatenge
Ashesh BasnetAshesh Basnet
Ashesh Basnet
AKAgnes Kilonzo-Nthenge
Agnes Kilonzo-Nthenge
The use of antibiotics in food animals results to antimicrobial resistant bacteria that complicates the ability to treat infections. The purpose of this study was to investigate the prevalence of pathogenic and commensal bacteria in soil, water, manure, and milk from cattle and goat farms. A total of 285 environmental and 81 milk samples were analyzed for Enterobacteriaceae by using biochemical and PCR techniques. Susceptibility to antibiotics was determined by the Kirby–Bauer disk diffusion technique. A total of 15 different Enterobacteriaceae species were identified from goat and cattle farms. Manure had significantly higher (p < 0.05) Enterobacteriaceae (52.0%) than soil (37.2%), trough water (5.4%), and runoff water (5.4%). There was a significant difference (p < 0.05) in Enterobacteriaceae in goat milk (53.9%) and cow milk (46.2%). Enterobacteriaceae from environment showed 100% resistance to novobiocin, erythromycin, and vancomycin E. coli O157:H7, Salmonella spp., Enterococcus spp., and Listeria monocytogenes displayed three, five, six, and ten. AMR patterns, respectively. NOV-TET-ERY-VAN was the most common phenotype observed in all isolates. Our study suggest that cattle and goat farms are reservoirs of multidrug-resistant bacteria. Food animal producers should be informed on the prudent use of antimicrobials, good agricultural practices, and biosecurity measures.

1 March 2017 in Journal of Food Protection
Verified
Journal Article
Closed access
SLSiqin Liu
Siqin Liu
AKAgnes Kilonzo-Nthenge
Agnes Kilonzo-Nthenge
The aim of this study was to determine whether U.S.-grown and imported fresh produce retailed in ethnic stores and chain supermarkets was a reservoir of antibiotic-resistant bacteria. A total of 360 (129 imported and 231 U.S.-grown) samples of fresh produce were purchased from retail stores and analyzed for Enterobacteriaceae, including three pathogenic bacteria (Escherichia coli O157:H7, Shigella, and Salmonella), using standard methods. Presumptive pathogenic isolates were confirmed using PCR. The mean Enterobacteriaceae counts for imported produce were 6.87 ± 0.15 log CFU/g and 7.16 ± 0.11 log CFU/g in ethnic stores and chain supermarkets, respectively. For U.S.-grown produce, the contamination levels were at 8.35 ± 0.17 log CFU/g and 7.52 ± 0.13 log CFU/g in ethnic stores and chain supermarkets, respectively. Salmonella (0 and 0.3%), Shigella (1.7 and 0.6%), E. coli (3.1 and 1.4%), Enterobacter (9.4 and 8.6%), Klebsiella (6.7 and 0.6%), and Serratia (5.8 and 1.4%) were detected in produce fro...

1 April 2015 in Journal of Food Protection
Verified
Journal Article
Closed access
AKAgnes Kilonzo-Nthenge
Agnes Kilonzo-Nthenge
ABA. Brown
A. Brown
SNS. N. Nahashon
S. N. Nahashon
DLD. Long
D. Long
Antibiotic-resistant bacteria existing in agricultural environments may be transferred to humans through food consumption or more multifaceted environmental paths of exposure. Notably, enterococcal infections are becoming more challenging to treat as their resistance to antibiotics intensifies. In this study, the prevalence and antibiotic resistance profiles of enterococci in organic and conventional chicken from retail stores were analyzed. Of the total 343 retail chicken samples evaluated, 282 (82.2%) were contaminated with Enterococcus spp. The prevalence was higher in organic chicken (62.5%) than conventional chicken (37.5%). Enterococcus isolates were submitted to susceptibility tests against 12 antimicrobial agents. Among the isolates tested, streptomycin had the highest frequencies of resistance (69.1 and 100%) followed by erythromycin (38.5 and 80.0%), penicillin (14.1 and 88.5%), and kanamycin (11.3 and 76.9%) for organic and conventional isolates, respectively. Chloramphenicol had the lowest fre...