Browsing by Author "Saidi, Bamusi"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Antimicrobial resistance of Escherichia coli isolated from chickens with Colibacillosis in and around Harare, Zimbabwe.
    (American Association of Avian Pathologists, 2012-11-14) Saidi, Bamusi; Mafirakureva, Prettimore; Mbanga, Joshua
    Colibacillosis, a disease caused by avian pathogenic Escherichia coli (APEC),can lead to great economic losses in the poultry industry. The aim of this study was to determine the prevalance of antibiotic resistance and antibiotic resistance and antibiotic resistance patterns in APEC in Zimbabwe. From 503 chickens diagnosed with Colibacillosis, 103 E. coli isolates were obtained. Isolation and identification of E. coli were carried out using microscopy and boichemical tests. The disc diffusion method was used to determine antibiotic susceptibility of the isolates to 8 commercial antibiotics. Many isolates exhibited resistance to more than one antibiotic. Antibiogram profiles indicated maximum resistance to tetracycline (100%), bacitracin(100%), and cloxacillin (100%) and a high prevalence of resistance to ampicillin(94.1%0. However; there were high prevalences of sensitivity to ciprofloxacin (100%) and gentamycin (97.1%). The isolates showed moderate rates of sensitivity to chloramphenicol and neomycin.All isolatesin this study showed multidrug resistance because they were all resistant to 3 or more antibiotics. Seven multidrug resistance patterns were observed. The most common pattern (resistance to ampicillin, bacitracin,cloxacillin and tetracycline) was exhibited by 30 isolates.Our findings show that there is emerging drug resistance in APEC associated with colibacillosis in Zimbabwe. The observed high level of multidrug resistance could hamper the treatment of colibacillosis in Zimbabwe.
  • Thumbnail Image
    Item
    An evaluation of the antimicrobial activities of aloe barbadensis:A. chabaudii and A. arborescens leaf extracts used in folklore veterinary medicine in Zimbabwe
    (2010) Mbanga, Joshua; Mangoma, Ngonidzashe; Saidi, Bamusi
    The antimicrobial activities of Aloe barbadensis Miller(Aloe vera), A. chabaudii and A. Arborescens sap extracts on selected microorganisms were determined. Methanol as well as aqueous extracts of these plants were obtained and then tested for their antimicrobial activities using the disc diffusion assay. The extracts were assayed againstgram positive bacteria (Staphylococcus aureus, Bacillus substilis), gram negative bacteria (Escherichia coli, Salmonella typhimurium, S. gallinarum, Klebsiellasp., Proteussp.) and Candida albicans. The study showed that the sap extracts of the three Aloes had antimicrobial activity against all the tested microorganisms. The antimicrobial activity of the methanol extracts were significantly higher than those of the aqueous (warm and cold) extracts (one tailed t-test, p<0.05). There was no significant difference in the antimicrobial activities of the aqueous extracts (one tailed t-test, p<0.05). S. typhimurium and S. gallinarum were the least susceptible to the extracts tested E. coli, Proteussp., Klebsiellasp. and C. albicans were the most sensitive.
  • Thumbnail Image
    Item
    Evolution of antimicrobial resistance of Salmonella enteritidis (1972–2005)
    (AOSIS OpenJournals, 2014-11-12) Khumalo, Jermaine; Saidi, Bamusi; Mbanga, Joshua
    With the extensive use of antibiotics in livestock production, surveillance revealed an increase in salmonella resistance to the commonly used antimicrobials in veterinary and public health. This serious threat to health care is further exacerbated by the limited epidemiological information about the common zoonotic agent, Salmonella enteritidis, required to determine antibiotic therapy. The aim was to characterise the antimicrobial resistance patterns of S. enteritidis isolates across different timelines (1972–2005) with accompanying genetic changes being investigated. Thirty-seven stored S. enteritidis isolates were collected from the Central Veterinary Laboratory, Harare, with antimicrobial susceptibility determined against eight antibiotics. Plasmids were isolated to analyse any genetic variation. An overall significant increase in resistance (p < 0.05) to nalidixic acid (0% – 10%), ampicillin (14.3% –50%), tetracycline (14.3% – 30%) and erythromycin (71.4% – 100%) was observed across the timeline. However, the highest rates of susceptibility were maintained for gentamicin, sulphamethoxazole-trimethoprim, kanamycin and chloramphenicol. We report an increase in multidrug resistance (MDR) of 14.2% – 50% with an increase in resistotypes and plasmid profiles across the timeline. Eleven plasmid profiles were obtained in the 37 isolates studied with a minority of isolates (21.6%, 8/37) harbouring a 54 kb plasmid, commonly serovarspecific. A concerning increase in antimicrobial resistance to commonly administered drugs was observed across the timeline. The surge in MDR is of great concern and implies the need for consistent antimicrobial stewardship. No correlation was observed between the plasmid and antibiotic profiles.
  • Thumbnail Image
    Item
    Identification of Foot and Mouth Disease Virus Isolates Using Vp1 Gene Sequencing
    (Zimbabwe Journal of Science & Technology, 2017) Dyirakumunda, Brighton; Saidi, Bamusi; Mbanga, Joshua
    Foot-and-mouth disease (FMD) is a severely infectious and economically devastating viral disease worldwide, which affects domestic animals with cloven hooves (artiodactyls) and more than 70 species of wild animals. The virus is highly variable with 7 serotypes and numerous subtypes. VP1 is the main immunogenic viral protein of FMDV and using Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and nucleotide sequencing, it can be used to characterize type, subtype and determine genetic distances among circulating FMD viruses. The aim of the study was to use VP1 gene sequencing to identify FMDV isolates obtained from the Central Veterinary Laboratory, Harare, Zimbabwe. A total of 35 probang samples were collected from the virology section at CVL. The samples consisted of stored probangs collected from FMDV infected cattle in 2014 and 2015. The VP1 gene was successfully amplified by RT-PCR in16 samples. Only 9 samples that had strong PCR bands were sequenced and used to identify FMD viruses using similarity based annotation approaches. Out of the 9 PCR products sequenced, 7 VP1 sequences were submitted to GenBank and assigned the following accession numbers: KT879751, KT879752, KT879753, KT879754, KT879755, KT879756 and KT879757. Similarity based annotation using BLAST analysis revealed that 5 of the isolates (KT879751, KT879752, KT879753, KT879754 and KT879755) belonged to the FMDV SAT 2 serotype. The remaining 2 isolates (KT879756 and KT879757) belonged to the FMDV SAT1 serotype. Phylogenetic analysis of these sequences using MEGA 7 showed that the viruses formed 3 clusters based on the VP1 gene sequences, 1 for SAT1 and 2 for SAT2, which implied that the SAT 2 isolates belong to 2 distinct topotypes. Our findings indicate that both the SAT2 and SAT1 serotypes are in circulation in Zimbabwe and that VP1 gene based sequencing is a useful tool for detection and identification of FMDV isolates.