scholarly journals Population Structure of Non-ST6 Listeria monocytogenes Isolated in the Red Meat and Poultry Value Chain in South Africa

2020 ◽  
Vol 8 (8) ◽  
pp. 1152
Author(s):  
Itumeleng Matle ◽  
Thendo Mafuna ◽  
Evelyn Madoroba ◽  
Khanyisile R. Mbatha ◽  
Kudakwashe Magwedere ◽  
...  

Meat products have been implicated in many listeriosis outbreaks globally, however there is a dearth of information on the diversity of L. monocytogenes isolates circulating in food products in South Africa. The aim of this study was to investigate the population structure of L. monocytogenes isolated in the meat value chain within the South African market. Based on whole-genome sequence analysis, a total of 217 isolates were classified into two main lineage groupings namely lineages I (n = 97; 44.7%) and II (n = 120; 55.3%). The lineage groups were further differentiated into IIa (n = 95, 43.8%), IVb (n = 69, 31.8%), IIb (n = 28, 12.9%), and IIc (n = 25, 11.5%) sero-groups. The most abundant sequence types (STs) were ST204 (n = 32, 14.7%), ST2 (n = 30, 13.8%), ST1 (n = 25, 11.5%), ST9 (n = 24, 11.1%), and ST321 (n = 21, 9.7%). In addition, 14 clonal complex (CCs) were identified with over-representation of CC1, CC3, and CC121 in “Processed Meat-Beef”, “RTE-Poultry”, and “Raw-Lamb” meat categories, respectively. Listeria pathogenic islands were present in 7.4% (LIPI-1), 21.7% (LIPI-3), and 1.8% (LIPI-4) of the isolates. Mutation leading to premature stop codons was detected in inlA virulence genes across isolates identified as ST121 and ST321. The findings of this study demonstrated a high-level of genomic diversity among L. monocytogenes isolates recovered across the meat value chain control points in South Africa.

Author(s):  
Valencia Vuyisile Ndlangamandla ◽  
Nontuthuko Rosemary Ntuli

Abstract Key message The morpho-agronomic and genetic studies recorded variations in vegetative and reproductive traits, and in molecular information through population structure and clustering approaches among South African Phaseolus vulgaris landraces. Abstract Phaseolus vulgaris L., commonly known as common beans, is widely used for its edible leaves, immature pods, and dry seeds. Studies on variation in morphology and genetics among P. vulgaris landraces are limited in South Africa. Therefore, the current study aimed to determine the morpho-agronomic and genetic variations among P. vulgaris landraces. Thirty-eight landraces from different agro-ecological origins, planted in a randomized complete block design, had their variation in vegetative and reproductive traits determined. These landraces were studied for their genetic diversity using simple sequence repeat (SSR) markers. The landraces were clustered in a biplot and dendrogram based on their seed coats, shape, similar morpho-agronomic traits, and their areas of origin. A total of 57 alleles were produced with a mean of 3.64 per SSR locus. The polymorphism information content ranged from 0.00 to 0.58. The population structure had the highest delta value K = 2, thus the 38 landraces were divided into two subpopulations based on the Bayesian approach. The population structure showed an overlap among the landraces as several from the Mesoamerican carried some seed traits or genes from the Andean gene pool, and showed a high level of admixtures. The principal coordinate analysis and the dendrogram had a similar clustering pattern as the population structure. This study revealed the potential markers with high diversity that can be used to determine genetically homogenous/heterogeneous landraces. Therefore, the use of PV-ctt001, PV-ag001, and PV-at003 could be beneficial in future breeding, conservation, and marker-assisted selection studies.


2020 ◽  
Vol 8 (1) ◽  
pp. 135 ◽  
Author(s):  
Christ-Donald Kaptchouang Tchatchouang ◽  
Justine Fri ◽  
Mauro De Santi ◽  
Giorgio Brandi ◽  
Giuditta Fiorella Schiavano ◽  
...  

Listeria species are Gram-positive, rod-shaped, facultative anaerobic bacteria, which do not produce endospores. The genus, Listeria, currently comprises 17 characterised species of which only two (L. monocytogenes and L. ivanovii) are known to be pathogenic to humans. Food products and related processing environments are commonly contaminated with pathogenic species. Outbreaks and sporadic cases of human infections resulted in considerable economic loss. South Africa witnessed the world’s largest listeriosis outbreak, characterised by a progressive increase in cases of the disease from January 2017 to July 2018. Of the 1060 laboratory-confirmed cases of listeriosis reported by the National Institute of Communicable Diseases (NICD), 216 deaths were recorded. Epidemiological investigations indicated that ready-to-eat processed meat products from a food production facility contaminated with L. monocytogenes was responsible for the outbreak. Multilocus sequence typing (MLST) revealed that a large proportion (91%) of the isolates from patients were sequence type 6 (ST6). Recent studies revealed a recurrent occurrence of small outbreaks of listeriosis with more severe side-effects in humans. This review provides a comparative analysis of a recently reported and most severe outbreak of listeriosis in South Africa, with those previously encountered in other countries worldwide. The review focuses on the transmission of the pathogen, clinical symptoms of the disease and its pathogenicity. The review also focuses on the major outbreaks of listeriosis reported in different parts of the world, sources of contamination, morbidity, and mortality rates as well as cost implications. Based on data generated during the outbreak of the disease in South Africa, listeriosis was added to the South African list of mandatory notifiable medical conditions. Surveillance systems were strengthened in the South African food chain in order to assist in preventing and facilitating early detection of both sporadic cases and outbreaks of infections caused by these pathogens in humans.


2020 ◽  
pp. 1-18
Author(s):  
Rhoda N. Ndanuko ◽  
Maria Shahid ◽  
Alexandra Jones ◽  
Terry Harris ◽  
Joel Maboreke ◽  
...  

Abstract Objective: To assess the contribution of different food groups to total salt purchases and to evaluate the estimated reduction in salt purchases if mandatory maximum salt limits in South African legislation were being complied with. Design: This study conducted a cross-sectional analysis of purchasing data from Discovery Vitality members. Data were linked to the South African FoodSwitch database to determine the salt content of each food product purchased. Food category and total annual salt purchases were determined by summing salt content (kg) per each unit purchased across a whole year. Reductions in annual salt purchases were estimated by applying legislated maximum limits to product salt content. Setting: South Africa Participants: The study utilised purchasing data from 344,161 households, members of Discovery Vitality, collected for a whole year between January and December 2018. Results: Vitality members purchased R12.8 billion worth of food products in 2018, representing 9,562 products from which 264,583 kg of salt were purchased. The main contributors to salt purchases were bread and bakery products (23.3%); meat and meat products (19%); dairy (12.2%); sauces, dressings, spreads and dips (11.8%); and convenience foods (8.7%). The projected total quantity of salt that would be purchased after implementation of the salt legislation was 250,346 kg, a reduction of 5.4% from 2018 levels. Conclusions: A projected reduction in salt purchases of 5.4% from 2018 levels suggests that meeting the mandatory maximum salt limits in South Africa will make a meaningful contribution to reducing salt purchases.


1998 ◽  
Vol 12 (1) ◽  
pp. 27-31
Author(s):  
N.P. du Preez ◽  
P. van Eldik ◽  
M. Möhr ◽  
H.H. van der Watt

In a two-part analysis (see pp 17–26 for Part 1), the authors discuss the key results of a South African project conducted during 1996 which focused on the factors relating to the development and establishment of technology in a country. The study investigated through a detailed questionnaire survey and a literature survey the various factors that promote the development and establishment of technology by comparing their perceived importance with the actual role they currently play in South Africa. This paper, Part 2, concentrates on the role of industry. The study showed that the availability of high-level technological people dominated the top (at 90%) of the list of factors relating to individual organizations and the role they play in the development of technology. Other prominent factors were the existence of a corporate technology strategy (88.4%), the need to improve manufacturing efficiency and processes (88.4%), the ability of top management to understand new technologies (87.9%), and the availability of funds for research and development (86.2%). The survey clearly indicated that South African organizations were not performing well with respect to these and other factors evaluated. All of them have been rated below 50%, indicating the seriousness of the problem. The corresponding recommendations made are of importance to younger countries with developing economies.


2016 ◽  
Vol 9 (3) ◽  
pp. 651-666 ◽  
Author(s):  
Johannes Van der Merwe ◽  
Philippus Cloete ◽  
Herman Van Schalkwyk

This article investigates the competitiveness of the South African wheat industry and compares it to its major trade partners. Since 1997, the wheat-to-bread value chain has been characterised by concentration of ownership and regulation. This led to concerns that the local wheat market is losing international competitiveness. The competitive status of the wheat industry, and its sub-sectors, is determined through the estimation of the relative trade advantage (RTA). The results revealed declining competitiveness of local wheat producers. Compared to the major global wheat producers, such as Argentina, Australia, Brazil, Canada, Germany and the USA, South Africa’s unprocessed wheat industry is uncompetitive. At the same time, South Africa has a competitive advantage in semi-processed wheat, especially wheat flour. The institutional environment enables the importation of raw wheat at lower prices and exports processed wheat flour competitively to the rest of Africa.


1985 ◽  
Vol 16 (4) ◽  
pp. 161-170
Author(s):  
F. E. Botha ◽  
J. H. Owens

The objective of this research was to establish the current image of training and development consultancy in South Africa in relation to the ideal as perceived by their clients. In view of the critical shortage of high-level manpower it was considered important to establish whether this service sector is effectively assisting organizations in developing their management to the required skill levels. Based on a survey of the literature on previous image studies, the research methodology combined the measurement of image by using a structured questionnaire with unstructured, subjective comment to arrive at a conclusion. The Repertory Grid technique was used to generate constructs for the semantic differential scale used in the questionnaire. This questionnaire was administered to training/personnel officials of a sample of manufacturing companies in the PWV area The responses to the questionnaire were analysed by means of basic descriptive statistics, factor analysis and t tests. Certain image dimensions were highlighted, and the results showed that numerous discrepancies existed between the image of training and development consultants and the perceived ideal. It was concluded that in order to effectively assist in alleviating the shortage of high-level manpower, training and development consultants should strive towards improving their analysis of problems, the correct identification of training needs and the customization of the training programmes to match specific South African corporate and cultural needs.


2020 ◽  
Vol 14 ◽  
pp. 117793222096210 ◽  
Author(s):  
Mariem Hanachi ◽  
Anmol Kiran ◽  
Jennifer Cornick ◽  
Emna Harigua-Souiai ◽  
Dean Everett ◽  
...  

Streptococcus pneumoniae serotype 1 is a common cause of global invasive pneumococcal disease. In New Caledonia, serotype 1 is the most prevalent serotype and led to two major outbreaks reported in the 2000s. The pneumococcal conjugate vaccine 13 (PCV13) was introduced into the vaccination routine, intending to prevent the expansion of serotype 1 in New Caledonia. Aiming to provide a baseline for monitoring the post-PCV13 changes, we performed a whole-genome sequence analysis on 67 serotype 1 isolates collected prior to the PCV13 introduction. To highlight the S. pneumoniae serotype 1 population structure, we performed a multilocus sequence typing (MLST) analysis revealing that NC serotype 1 consisted of 2 sequence types: ST3717 and the highly dominant ST306. Both sequence types harbored the same resistance genes to beta-lactams, macrolide, streptogramin B, fluoroquinolone, and lincosamide antibiotics. We have also identified 36 virulence genes that were ubiquitous to all the isolates. Among these virulence genes, the pneumolysin sequence presented an allelic profile associated with disease outbreaks and reduced hemolytic activity. Moreover, recombination hotspots were identified in 4 virulence genes and more notably in the cps locus ( cps2L), potentially leading to capsular switching, a major mechanism of the emergence of nonvaccine types. In summary, this study represents the first overview of the genomic characteristics of S. pneumoniae serotype 1 in New Caledonia prior to the introduction of PCV13. This preliminary description represents a baseline to assess the impact of PCV13 on serotype 1 population structure and genomic diversity.


1998 ◽  
Vol 12 (1) ◽  
pp. 17-26
Author(s):  
N.P. du Preez ◽  
P. van Eldik ◽  
M. Möhr ◽  
H.H. van der Watt

In a two-part analysis (Part 2 follows on pp 27–31), the authors discuss the key results of a South African project conducted during 1996 which focused on the factors relating to the development and establishment of technology in a country. The study investigated through a detailed questionnaire survey and a literature survey the various factors that promote the development and establishment of technology by comparing their perceived importance with the actual role they currently play in South Africa. This paper, Part 1, concentrates on the role of higher education. The importance of academic institutions in supplying high-level human resources was rated very highly (90.47%) but the role it is currently playing in reality was rated at 52.8%. Closely connected with this, the availability of high-level skilled technological people was given an importance of 89% while the current reality was rated at only 43%. This clearly shows that the South African higher education system is performing poorly in addressing these vital needs. The availability of entrepreneurs with innovative and creative skills to participate in the development and diffusion of technology was given an importance rating of 84.3% against a current situation of 42.2%, again indicating South Africa's weak performance. The results of the survey and the consequent recommendations are important to all developing countries with newly industrial economies.


2019 ◽  
Vol 24 (1) ◽  
pp. 32-55 ◽  
Author(s):  
Geoffrey Wood ◽  
Christine Bischoff

Purpose The central purpose of this paper is to explore how implicit knowledge capabilities and sharing helps secure organizational survival and success. This article explores the challenging in better management knowledge in the South African clothing and textile industry. In moving from a closed protected market supported by active industrial policy, South African manufacturing has faced intense competition from abroad. The ending of apartheid removed a major source of workplace tension, facilitating the adoption of higher value-added production paradigms. However, most South African clothing and textile firms have battled to cope, given cutthroat international competition. The authors focus on firms that have accorded particularly detailed attention to two instances characterized by innovative knowledge management. The authors highlight how circumstances may impose constraints and challenges and how they paradoxically also create opportunities, which may enable firms to survive and thrive through the recognition and utilization of informal knowledge, both individual and collective. Design/methodology/approach This study is based on in-depth interviews, primary company and industry association and secondary documents. Findings The study highlights how successful firms implemented systems, policies and practices for the better capturing and utilization of external and internal knowledge. In terms of the former, a move toward fast fashion required and drove far-reaching organizational restructuring and change. This made for a greater integration of knowledge through the value chain, ranging from design to retail. Successful firms also owed their survival to the recognition and usage of internal informal knowledge. At the same time this process was not without tensions and paradoxes, and the findings suggest that many of the solutions followed a process of experimentation. The latter is in sharp contrast to many South African manufacturers, who, with the global articulation of production networks, have lost valuable knowledge on suppliers and their practices. At the same time, both firms have to contend with an increasingly unpredictable international environment. Research limitations/implications At a theoretical level, the study points to the need to see informal knowledge not only in individualistic terms but also as a phenomenon that has collective, and indeed, communitarian features. Again, it highlights the challenges of nurturing and optimizing informal knowledge. It shows how contextual features both constrain and enable this process. It further highlights the extent to which the effective utilization of external knowledge, and rapid responses to external developments, may require a fundamental rethinking of organizational structures and hierarchies. This study focuses on a limited number of dimensions of this in a single national context but could be replicated and extended into other contexts. Practical implications The study highlights the relationship between survival, success and how knowledge is managed. This involved harnessing the informal knowledge and capabilities of workforce to enhance productivity, in conjunction with improvements in machinery and processes, and a much closer integration of design, supply, production and marketing, underpinned by a more effective usage of IT. Paradoxically, other clothing and textile firms have survived doing the exact opposite – reverting to low value-added cut-and-trim assembly operations. At a policy level, the study highlights how specific features of South African regulation (above all, in terms of job protection), which are often held up as barriers to competiveness, may help sustain the knowledge base of firms. Social implications The preservation and creation of jobs in a highly competitive sector was bound up with effective knowledge management. The study also highlighted the mutual interdependence of employers and employees in a context of very high unemployment and how the more effective usage of informal knowledge bound both sides closer. Originality/value There is a fairly diverse body of literature on manufacturing in South Africa, and, indeed across the continent; however, much of it has focused on challenges. This study explores relative success stories from a sector that has faced a structural crisis of competitiveness, and as such, has relevance to understanding how firms and industries may cope in highly adverse circumstances.


2017 ◽  
Vol 74 (11) ◽  
pp. 1895-1903 ◽  
Author(s):  
Carryn L. de Moor ◽  
Douglas S. Butterworth ◽  
Carl D. van der Lingen

Differences in parasite infection have previously been used to distinguish between fish stocks. We demonstrate a novel use of parasite prevalence-by-length data to inform quantitatively on stock mixing. An initial two mixing stock hypothesis proved consistent with biological and survey data, suggesting that there are different stocks of sardine off the west and south coasts of South Africa. That hypothesis assumed that only recruits moved from the west to the south stock. However, new “tetracotyle”-type metacercarian parasite bio-tag data indicate a need to allow older fish to move between the stocks as well. We demonstrate extension of bio-tagging to inform on the plausibility of population structure hypotheses by including parasite prevalence-by-length data in the model’s likelihood. Our method enables the estimation of the magnitude of mixing between semidiscrete stocks, providing more precise estimates of annual movement. Such improved precision may be important in better informing future movement hypotheses and thereby management. Our research provides a framework to use to inform quantitatively on stock structure and movement hypotheses for other fish species with bio-tagging data.


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