Tizazu Zelelie

Mr. Tizazu Zelelie

Addis Ababa University, College of Health Sciences

Research Focus & Metrics

Academic Career Length

57Years (1970-Present)

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

Representative Publications

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1 January 2019 in Toxicology Reports
Verified
Journal Article
Open access
ELErmias Lulekal
Ermias Lulekal
STSolomon Tesfaye
Solomon Tesfaye
SGSelam Gebrechristos
Selam Gebrechristos
KDKassahun Dires
Kassahun Dires
TZTizazu Zelelie
Tizazu Zelelie
AAAwol Mekonnen Ali
Awol Mekonnen Ali
Cymbopogon citratus has been used by the local people in Ankober district, northern Ethiopia, as traditional medicine to treat various ailments. Its essential oil has been shown to have antibacterial, antifungal, antiprotozoal, anti-carcinogenic, anti-inflammatory and antioxidant activities amongst others. This study was conducted to determine skin irritation, acute and subacute toxicity of C. citratus essential oil in mice and rabbits. The essential oil was analyzed using GC-MS. The essential oil at dose of 2000 mg/kg body weight was administered to mice for 21 consecutive days. The mice mortality, behavioral change, injury and other signs of illness were recorded once daily. Biochemical parameters were evaluated. Liver and kidney were taken after sacrifice for gross findings and histological analyses. 10 % ointment formulation of C. citratus oils was applied on the rabbit skin to determine skin irritation effects. The result revealed, the presence of citral (71.297%), myrcene (19.034%), 4, 5-epoxycarene (2.780%), linalool (1.713%), ((S)-cis-verbenol (1.110 %), linalool (1.713 %), ((S)-cis-verbenol (1.110 %) and undecan-2-one (1.001 %) in the C. citratus essential oil. There was no significant difference (p > 0.05) in the body weights, gross abnormalities of the organs and biochemical parameters compared to the control. No histopathological changes were detected in the organs tested. 10 % ointment formulation of C. citratus oils did not cause skin irritation. Analysis of results leads to the conclusion that Ethiopian C. citratus essential oil may be considered as relatively safe and non-toxic.

27 January 2019 in Journal of Toxicology
Verified
Journal Article
Open access
PDF file
AAAwol Mekonnen Ali
Awol Mekonnen Ali
STSolomon Tesfaye
Solomon Tesfaye
SCSelam G. Christos
Selam G. Christos
KDKassahun Dires
Kassahun Dires
TZTizazu Zelelie
Tizazu Zelelie
ELErmias Lulekal
Ermias Lulekal
Lavandula angustifolia is used in traditional and folk medicines of Ankober District, North Central Ethiopia, for the treatment of several livestock and human disorders. This toxicity study aimed to investigate L. angustifolia essential oil oral toxicity in mice and skin irritation in rabbit. L. angustifolia essential oil was analyzed using gas chromatography-mass spectrometry methods and showed predominance of Eucalyptol (52.36%), Camphor (11.91%), gamma-terpinene (8.775%) and endoborneol (7.585%). Limit test at 2000 mg/kg dose was used for L. angustifolia essential oil acute toxicity test and revealed LD50 value was higher than 2000 mg/kg. For subacute toxicity study 2000mg/kg was given orally to each mouse for 21 days. The result demonstrated no significant changes (p > 0.05) in the body weights, and biochemical parameters, gross abnormalities, water, and food intake were observed. No macroscopic changes were seen in the histopathology analysis of kidneys and livers. For skin irritation test shaved rabbit skin was treated with 10% ointment formulation. Ointment of L. angustifolia oil did not affect mice skin. Generally, this toxicity study demonstrated that L. angustifolia essential oil is nontoxic.

10 December 2020 in Annals of Clinical Microbiology and Antimicrobials
Verified
Journal Article
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TZTizazu Zelelie
Tizazu Zelelie
NZNiguse Zegeye
Niguse Zegeye
TETadesse Eguale
Tadesse Eguale
Background: Campylobacter jejuniandCampylobacter coliaccounts for most cases of human gastrointestinal infections. The infection occurs through ingestion of contaminated food or water, and direct contact with feces of infected animal or human. Regardless of few local reports ofCampylobacterand its antimicrobial susceptibility profile, there is no comprehensive data that show the burden ofCampylobacterinfection at national level in Ethiopia. This systemic review and meta-analysis aimed to determine the pooled prevalence ofCampylobacterand its resistance patterns in Ethiopia from different sources.Method: A comprehensive literature search of PubMed, Google scholar, Science direct and Google engine search was conducted for studies published from 2000 to July 30, 2020 on prevalence and antimicrobial susceptibility ofCampylobacterin human, animal and food. The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Checklist. Data from articles was extracted using a standardized data extraction format. The quality of the studies was assessed based on the Newcastle–Ottawa scale. The Q test and I2test statistic were used to test heterogeneity across studies. The Pooled estimate of prevalence ofCampylobacterspecies and its antimicrobial susceptibility profile was computed by a random effects model using STATA 16.0 software. Results were presented in forest plot, tables, funnel plot and figures with 95% confidence interval.Results: A total of 291 articles were retrieved initially. The pooled prevalence ofCampylobacter speciesfrom different sources was 10.2% (95% CI 3.79, 16.51). In this meta-analysis, the lowest prevalence was 6.0% whereas the highest prevalence was 72.7%. In the sub-group analysis, the pooled prevalence was similar in Amhara and Oromia region, higher in Gambella and lower in Sidama. Prevalence ofCampylobacterwas higher in animals (14.6%) compared to humans (9%). The pooled antimicrobial resistance rates ofCampylobacter speciesto different antimicrobials ranged from 2.9–100%. Overall, higher rate of resistance was to cephalothin (67.2%), gentamicin (67.2%), and trimethoprim-sulfamethoxazole (33.3%) inCampylobacterisolates from all sources. In isolates from human, resistance to cephalothin was 83% followed by amoxicillin (80%), amoxicillin-clavulnate (36%), trimethoprim-sulfamethpxazole (32%), clindamycin (31%) and ceftriaxone (28%). On the other hand, higher rate of resistance to penicillin (100%), cephalothin (60%), ciprofloxacin (71.2%), and trimethoprim-sulfamethoxazole (39%) was recorded in isolates from animals.Conclusion: The present study highlights the burden ofCampylobacter speciesin the country and higher rate of resistance among investigated isolates. Designing appropriate prevention strategies and further local in-depth studies are recommended to establish actual epidemiological burden of the bacteria in the country.

21 August 2016 in The Brazilian Journal of Infectious Diseases
Verified
Journal Article
Open access
TZTizazu Zelelie
Tizazu Zelelie
ETErmias Tefera
Ermias Tefera
Evaluating the outcomes of tuberculosis treatment and understanding the specific reasons for unfavorable treatment outcome are important in evaluating the effectiveness of tuberculosis control program. A retrospective study was conducted to assess tuberculosis treatment outcomes and associated factors among smear positive pulmonary tuberculosis patients in zone-one health facilities of Afar regional state, Ethiopia. A total of 380 smear positive pulmonary tuberculosis patients' registration book recorded with complete information from Jan 2011 to Dec 2013 were analyzed. Of 380 patients included in the analysis, 238 were male and 142 female with mean age of 30.7. Overall treatment outcome were 128 (33.7%) cured, 192 (50.2%) completed, 17 (4.5%) died, 1 (0.3%) treatment failure, 34 (8.9%) default and 8 (2.1%) transfer out. Treatment success rate was 81.8%. There was statistically significance association between age (p-value=0.000), sex (p-value=0.018), HIV status (p-value=0.000), four week attendance (p-value=0.000), sputum follow up test (p-value=0.000), and treatment outcome year (p-value=0.000), and treatment success (p-value=0.000). Treatment success rate almost reached to the WHO targets although yet need to work a lot for fulfillment of global targets. Regular four week attendance in continuation phase and doing follow up sputum test with unsuccessful outcome for smear positive tuberculosis patient were vital.

14 July 2023 in PLOS ONE
Verified
Journal Article
Open access
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TZTizazu Zelelie
Tizazu Zelelie
TETadesse Eguale
Tadesse Eguale
BYBerhanu Yitayew
Berhanu Yitayew
DADessalegn Abeje
Dessalegn Abeje
AWAshenafi Alemu Wami
Ashenafi Alemu Wami
TATamrat Abebe
Tamrat Abebe
Background: Diarrhea is a serious health problem in children, with the highest mortality rate in sub-Saharan Africa. Diarrheagenic Escherichia coli (DEC) is among the major bacterial causes of diarrhea in children under age five. The present study aims to determine molecular epidemiology and antimicrobial resistance profiles of DEC and identify contributing factors for acquisition among children under age five in Central Ethiopia. Methods: A health facility-centered cross-sectional study was conducted in Addis Ababa and Debre Berhan, Ethiopia, from December 2020 to August 2021. A total of 476 specimens, 391 from diarrheic and 85 from non-diarrheic children under age five were collected. Bacterial isolation and identification, antimicrobial susceptibility, and pathotype determination using polymerase chain reaction (PCR) were done. Results: Of the 476 specimens analyzed, 89.9% (428/476) were positive for E. coli, of which 183 were positive for one or more genes coding DEC pathotypes. The overall prevalence of the DEC pathotype was 38.2% (183/476). The predominant DEC pathotype was enteroaggregative E. coli (EAEC) (41.5%, 76/183), followed by enterotoxigenic E. coli (21.3%, 39/183), enteropathogenic E. coli (15.3%, 28/183), enteroinvasive E. coli (12.6%, 23/183), hybrid strains (7.1%, 13/183), Shiga toxin-producing E. coli (1.6%, 3/183), and diffusely-adherent E. coli (0.6%, 1/183). DEC was detected in 40.7% (159/391) of diarrheic and 28.2% (24/85) in non-diarrheic children (p = 0.020). The majority of the DEC pathotypes were resistant to ampicillin (95.1%, 174/183) and tetracycline (91.3%, 167/183). A higher rate of resistance to trimethoprim-sulfamethoxazole (58%, 44/76), ciprofloxacin (22%, 17/76), ceftazidime and cefotaxime (20%, 15/76) was seen among EAEC pathotypes. Multidrug resistance (MDR) was detected in 43.2% (79/183) of the pathotypes, whereas extended spectrum ß-lactamase and carbapenemase producers were 16.4% (30/183) and 2.2% (4/183), respectively. Conclusion: All six common DEC pathotypes that have the potential to cause severe diarrheal outbreaks were found in children in the study area; the dominant one being EAEC with a high rate of MDR.

 in Ethiopian Journal of Health Sciences
Verified
Journal Article
Open access
PDF file
TZTizazu Zelelie
Tizazu Zelelie
DGDemissew Shenkute Gebreyes
Demissew Shenkute Gebreyes
ATAlemnesh Tesema Tilahun
Alemnesh Tesema Tilahun
HCHillary A. Craddock
Hillary A. Craddock
NGNigus Zegeye Gishen
Nigus Zegeye Gishen
BACKGROUND: Diarrheal disease is a major cause of mortality and morbidity for under-five children in Ethiopia. The purpose of this study was to investigate the behavioral and socioeconomic risk factors, etiology, and drug susceptibility of bacteria isolated from under-five children with acute diarrhea who were treated at Debre Berhan Referral Hospital or Health Center in Ethiopia.METHODS: A health facility based cross-sectional study design was used to investigate enteropathogens from 163 under-five children with acute diarrhea. After obtaining written consent from parents or guardians, data were collected using a standardized questionnaire. Freshly passed stool samples were collected for microbiological tests for bacteria and parasites. The chi-square test was used for assessing the relationships of variables.RESULTS: Enteropathogens were detected among 55.8% (91/163) participants. There was a 46%(75/163) bacterial culture positivity rate and a 9.8%(16/163) prevalence of parasites. The isolated enteropathogens were Escherchia coli, Klebsiella specie, Proteus species, Salmonella species, Shigella species, Enterobacter species, Giardia lamblia, Enteameba histolytica, Ascaris lumbricoides, Trichuris trichiura and Hymnoleps nana. Level of antimicrobial resistance of bacterial isolates ranged from 0 to 87.2%. Poor hand washing and poor cleaning of feeding utensils showed significant association with the presence of enteropathogens.CONCLUSION: Bacterial enteropathogens with drug resistance were observed in this study. Continuous health education and promotion about diarrheal disease for mothers/caretakers and regular surveillance of entropathogenes are recommended to reduce under-five mortality.