Browsing by Author "Erku Woldaregay"

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Bacteriological Analyses of Weaning Foods and Growth Potential of Some Food borne Pathogens in Weaning Foods
    (Addis Ababa University, 1997-06) Erku Woldaregay; Ashenafi Mogessie (PhD)
    One hundred samples of feeding-bottles were collected from infants and young children coming to four clinics in Addis Ababa, from November, 1996 to April, 1997. Information on sex, age, number of bottles used, educational status of the mother and ingredients of bottle content were collected through interview. The bacteriology of these samples was analysed using standard microbiological techniques. The analyses showed that all the samples had heavy bacterial contamination, the mean count being in the levei of 107 c.f.u / ml. Only 17% of the samples had count l'O6 c. f. u /ml. The two most *commonly encountered bottle contents (cow's milk and cereal blend) were the most heavily contaminated. About 52% of the milk and 93% of cereal blend had count more than 107 c.f.u/ml. The contamination level was found to be affected by ingredients of bottles used and educational status of mothers. About 90% of the samples prepared by illiterate mothers had count over 107 c.f.u/ml. The percentages for elementary and high school educated mothers for the corresponding load were 85 and 79, respectively. Three hundred and sixty-nine bacterial isolates, grouped into 12 genera were identified from the bottle content. Thirty-seven per cent of the samples had 3 isolates, whereas 21% and 16% of the samples were contaminated with 4 and 2 isolates, respectively. The dominant organisms were coliforms (34%) followed by Staphylococci (28 %), Bacillus spp . (19%) Micrococcus spp. (14%) and other (3%). Three isolates of Salmonella spp. of the same serogroup were also identified. Cow's milk harboured 219(59%) of the isolates followed by gruel made of cereal blend(16%). A total of 30 factory-produced weaning foods (product A, B and C), and 20 of the two most frequently encountered home-made bottle-contents (cow's milk and cereal blend) were prepared at home by mothers under close supervision. The bacteriological analyses of these foods showed that only 30% of the factory-produced weaning foods had bacterial count over 102 c.f.u/ ml(g). The count from the two home-made bottle contents was also low; only 15% of the samples had bacteria 102 c.f. u/ml. These signifies that food handling and the gap between consumption and preparation must be important in this regard. The organisms isolated from the above 50 samples were Bacillus spp., for they were the only organisms that could tolerate the heat treatment. The growth potential of Salmonella sp. in products 'C' and cereal blend was determined. It was found out that it reached to a level of 107 c.f.u ./ml(g) in 12 hours and 10s c.f.u/ml(g) in 16 hours. If weaning foods have initial contamination of 103 c.f.u./ml (g) (which by itself is beyond the threshold level for infants) it reaches to unacceptably high level within 8 hours (10G c.f.u/mlg)In order to intervene with food borne diseases of infants and children, mothers must be taught of food safety principles. Increasing the number of bottles used to feed infants to three or more could also be helpful in reducing food borne bacterial contamination . More important is teaching and encouraging mothers to consider the use of fermented food products as alternatives, which are cost-effective means of reducing bacterial pathogens in weaning foods.
  • No Thumbnail Available
    Item
    Molecular Epidemiology and Drug-resistance Pattern of Mycobacterium Tuberculosis Isolates from Amhara, Gambella and Benishangul-Gumuz Regions of Ethiopia
    (Addis Ababa University, 2022-03) Yenew Bazezew; Erku Woldaregay; Kebede Abebaw
    Background: Globally, tuberculosis (TB) has affected human beings for thousands of years and the emergence of drug-resistant tuberculosis has been a major obstacle to control the disease, especially in developing countries including Ethiopia. Objective: The study investigated the molecular epidemiology and drug resistance pattern of M. tuberculosis circulating in the Amhara, Gambella and Benshangul-Gumuz regions of Ethiopia. Methods: A cross-sectional study was conducted using 128 MTBC isolates that were obtained from presumptive TB/MDR-TB patients. A total of 127 recovered isolates were used to investigate drug resistance patterns with the indirect proportion method using the MGIT 960 system and the genotypic method at the Ethiopian Public Health Institute. Further, identification of mycobacterial strain types and mycobacterial lineages was done using spoligotyping. Data were managed using the Epi-info, SPSS version 25, SITVIT2, MIRU-VNTRplus and TBInsight databases. Results: Of the 127 recovered mycobacterial isolates, 100 (78.7%) were sensitive to the four firstlineanti-TB drugs, but 27 (21.3%) were resistant to at least one anti-TB drug,20 (15.7%) were poly-resistant, 17 (13.4%) were multi-drug resistant and 2 (10.5%) were Pre-XDR. The highest gene mutations associated with INH and RIF resistance were observed in the katG MUT1 gene (S315T1) [20 (76.9%)] and rpoB gene (S531L) [10 (52.6%)], respectively. Further, the two preXDR cases showed mutations in the gyrA gene. Among the 127 spoligotyped isolates, 119 generated 43 different spoligotyping patterns; 87 (73.1%) generated 26 distinct spoligotype patterns; and 31 (26.0%) generated 17 different spoligotype patterns. The predominantly identified strains, family, lineages and sublineages were the SIT149 (19, 15.9%), T family (54, 45.4%), EuroAmerican (72,60.5%) and CAS1-Delhi (24, 20.2%), respectively. Additionally, Mycobacterium Africanum (12,10.1%) was identified. Furthermore, drug resistance was significantly associated with previous TB history(X2=46.59; p<0,001) and previous TB treatment outcome (X2=47.677;p<0.001). Conclusion: The study identified a significant proportion of drug resistant TB (monoresistance, MDR, Pre-XDR) which could imply the drug resistant TB is a major public health problem in the country. Although a diversified mycobaterium lineages were observed in this study, the Euro American lineage and East-African-Indian lineages were the predominant lineages with the respective CAS1-Delhi and T3-ETH sublineages that are strongly associated with the druresistant TB. Consequently, the country should focuse on the strategies that help for early detection and treatment of drug-resistant TB to halt the transmission of the disease. We recommend further molecular characterization of the unknown mycobacterial isolates, particularly using sequencing platforms and phenotypic drug susceptibility testing to first- and second-line drugs. Besides, the country’s tuberculosis control program should monitor patient adherence to ensure the patients complete the full course of treatment.