Molecular detection and drug susceptibility of Mycobacterium tuberculosis complex in raw milk from a major dairy farm in the Nkonkobe region, Eastern Cape Province, South Africa
- Authors: Silaigwana, Blessing https://orcid.org/0000-0002-3324-1607
- Date: 2012
- Subjects: Mycobacterium tuberculosis , Drug resistance in microorganisms , Tuberculosis -- Pathogenesis
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24239 , vital:62543
- Description: Mycobacterium tuberculosis complex (MTBC) organisms are the causative agents of tuberculosis in humans as well as animals. The study aimed to use molecular techniques for detection and drug susceptibility testing of MTBC in raw milk from cattle at a dairy farm in the Nkonkobe region of South Africa. Two hundred samples (100mL each) were collected and processed using the modified Petroff’s method. DNA was isolated using the Zymo Research bacterial DNA kit and amplified using the Seeplex® MTB Nested ACE assay. Drug susceptibility testing was performed using the Genotype® MTBDRplus assay. MTBC DNA was detected in 11 (6percent) of the samples tested. Resistance to both rifampicin and isoniazid was detected in 90.9percent of the positive samples. The most frequent rpoB mutations detected were H526Y (90percent), H526D (80percent), S531L (60percent) and D516V (20percent). No mutation was detected in the katG gene. All isoniazid resistant samples harboured mutations in the inhA gene. The most frequent (100percent) mutation conferring low level isoniazid resistance was the T8A substitution. The inhA mutations C15T, A16G and T8C were equally represented with 60percent frequency. A high prevalence of multi-drug resistance was noted in the Nkonkobe region. Therefore, the results of this study have clinico-veterinary and epidemiological significance and calls for further studies and necessary actions to delineate the situation. , Thesis (MSc) -- Faculty of Science and Agriculture, 2012
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- Date Issued: 2012
The measurement of genetic diversity in mycobacterium tuberculosis using random amplified polymorphic DNA profiling
- Authors: Richner, Sharon M
- Date: 2000
- Subjects: Tuberculosis -- History -- 20th century , Tuberculosis -- Africa, Southern , Tuberculosis -- Treatment , Tuberculosis -- Africa , Tuberculosis -- Prevention , Tuberculosis -- Pathogenesis , Mycobacterium tuberculosis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4008 , http://hdl.handle.net/10962/d1004068 , Tuberculosis -- History -- 20th century , Tuberculosis -- Africa, Southern , Tuberculosis -- Treatment , Tuberculosis -- Africa , Tuberculosis -- Prevention , Tuberculosis -- Pathogenesis , Mycobacterium tuberculosis
- Description: Mycobacterium tuberculosis has caused a resurgence in pulmonary disease in both developed and developing countries in recent times, particularly amongst people infected with the human immunodeficiency virus. The disease has assumed epidemic proportions in South Africa and in the Eastern Cape Province in particular. Of further concern is the isolation of increasing numbers of multiply drug resistant strains. Knowledge of the genetic capability of this organism is essential for the successful development of novel antibiotics and vaccines in an attempt to bring the global pandemic under control. Measurement of the genetic diversity of the organism may significantly contribute to such knowledge, and is of vital importance in monitoring epidemics and in improving treatment and control of the disease. This will entail answering a number of questions related to the degree of genetic diversity amongst strains, to the difference between urban and rural strains, and between drug resistant and drug sensitive strains, and to the geographical distribution of strains. In order to establish such baseline information, RAPD profiling of a large population of isolates from the western and central regions of the Eastern Cape Province was undertaken. A smaller number of drug resistant strains from a small area of KwaZulu-Natal were also analysed, with a view to establishing the genetic difference between strains from the two provinces. Cluster analysis, analysis of molecular variance and Geographical Information Systems technology were used to analyse the RAPD profiles generated. An unexpectedly high degree of genetic diversity was detected in strains from both provinces. While no correlation was seen between genetic diversity and either urban-rural situation or geographical location, a small degree of population structure could be correlated with drug resistance in the Eastern Cape. Furthermore, a significant degree of population structure was detected between strains from the two provinces, although this was still within the parameters for conspecific populations. Future work is necessary to further characterise strains from rural areas of both provinces, as well as from the eastern region of the Eastern Cape in an attempt to pinpoint the cause of the separation of the provincial populations.
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- Date Issued: 2000