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Population structure and phylogenetic analysis of Vibrio cholerae non-O1/O139 by whole genome sequencing
Wells, Taylor; González-Durán, Elizabeth; Smith, Anthony Marius; Banerjee, Swapan K.; Tamber, Sandeep; Knox, Natalie; Nadon, Celine (Public Library of Science, 2026-03-05)
Toxigenic Vibrio cholerae serogroups O1 and O139 are well known for causing excessive diarrhea leading to devastating cholera epidemics and pandemics. Over 200 other serogroups, usually lacking the cholera toxin, are denoted non-O1/O139 V. cholerae (NOVC), and cause vibriosis leading to sporadic gastroenteritis and other extraintestinal infections. NOVC infections are not a notifiable disease in Canada and thus underreported. From 2010 to 2023, 160 cases and a small 2018 outbreak were reported in Canada caused by NOVC, provoking considerable public health concern. In this study, 242 Canadian V. cholerae isolates were sequenced, characterized and compared with over 1500 other V. cholerae isolates from around the world to determine their genetic relationships. All Canadian NOVC and two O139 isolates lacked the cholera toxin-producing genes typically harbored by pathogenic O1 and O139. All 14 Canadian O1 isolates were identified from travel-related cases as members of the toxigenic 7th pandemic lineage, whereas one O139 isolate was acquired domestically. Phylogenetic analysis based on core genome single nucleotide polymorphisms classified the Canadian isolates into five clades. Eight new lineages of NOVC, denoted CAD1–8, were identified from the Canadian isolates. A new lineage was defined as clusters formed by three or more isolates in the phylogeny. These lineages were comprised of isolates from clinical origin alone, environmental origin, or a mixture of both. Some lineages spanned multiple years and regions. CAD-2 was comprised of clinical and environmental isolates associated with the 2018 outbreak. Several virulence genes were detected among NOVC, including hemolysins, toxins and secretion system encoding genes. A proportion of virulence genes differed between isolation source (clinical or environmental) and clinical manifestations (gastrointestinal or extraintestinal). Our study identified environmental sources of NOVC with the potential to cause human infection. Tracking the emergence of NOVC with pathogenic potential is essential for understanding the risk to Canadians.
Population impact of South Africa's human papillomavirus (HPV) vaccination programme on HPV prevalence in adolescent girls with and without HIV : a repeat cross-sectional study
Machalek, Dorothy A.; Nyemba, Dorothy C.; Travill, Danielle; Petoumenos, Kathy; Mbulawa, Zizipho Z.A.; Naidoo, Ishana; Motshwane, Feni M.M.; Bamford, Lesley; Rees, Helen; Kaldor, John M.; Delany-Moretlwe, Sinead (Elsevier, 2026-04)
BACKGROUND : A school-based human papillomavirus (HPV) vaccination programme providing protection against types 16 and 18 of HPV was introduced in South Africa in 2014 for Grade 4 girls (aged ≥9 years), achieving 87% coverage among learners with at least one of the two recommended doses. We evaluated the programme's impact on HPV prevalence among adolescent girls in a setting of high HIV prevalence. METHODS : In this repeat cross-sectional study, girls aged 17–18 years were invited from 15 primary health-care clinics in four provinces (Free State, Gauteng, Mpumalanga, and North West) of South Africa to provide a self-collected vaginal sample for HPV testing (AnyPlex II HPV28, Seegene, Seoul, South Korea). A survey done from June 19 to Dec 11, 2019, estimated baseline (pre-vaccine) HPV prevalence. A repeat survey done from Feb 16 to Dec 6, 2023, estimated HPV prevalence in a group eligible for the vaccination programme (post-vaccine). Vaccination status was assessed through district registers and self-reported data. The primary outcome was the impact of the HPV vaccination programme, measured as the relative reduction in HPV prevalence between the two birth cohorts using generalised linear regression (estimating adjusted prevalence ratios), overall and by HIV status. FINDINGS : Of 2470 participants enrolled, 819 girls were recruited for the pre-vaccine survey (248 living with HIV) and 1538 for the post-vaccine survey (295 living with HIV). Prevalence of HPV vaccine types HPV-16 and HPV-18 declined by 83%, from 21·6% (177 of 819 participants) in the pre-vaccine group to 3·2% (49 of 1538 participants) in the post-vaccine group (adjusted prevalence ratio 0·17, 95% CI 0·12–0·24; p<0·0001). A similar reduction was observed among those living with HIV, with prevalence decreasing from 29·4% (73 of 248 participants) in the pre-vaccine group to 4·4% (13 of 295 participants) in the post-vaccine group (adjusted prevalence ratio 0·18, 95% CI 0·10–0·32; p<0·0001). No significant reductions were noted for other HPV types, except HPV-31 and HPV-45, which is consistent with cross-protection. INTERPRETATION : In this large-scale evaluation of South Africa's two-dose HPV vaccination programme, we observed impacts similar to those seen with three-dose programmes in high-income settings, including equivalent impacts among adolescent girls living with HIV. These findings underscore the substantial population-level benefits of high-coverage routine HPV vaccination in a high-HIV-burden setting.
Afrikaans het wesenlik as amptelike taal verval
Malan, Jacobus J. (Koos) (Suid Afrikaanse Akademie vir Wetenskap en Kuns, 2026-03)
AFRIKAANS : Ofskoon Afrikaans op 8 Mei 2025 honderd jaar een van Suid-Afrika se amptelike tale was, het dit, gemeet aan sy daadwerklik amptelike gebruik sedert die inwerkingtreding van die huidige grondwetlike bedeling in 1994, maar veral sedert die 1996-grondwet van krag geword het, in beduidende mate as amptelike taal verval. ’n Oorweging van die vyf belangrikste gebiede van die amptelike gebruik van ’n taal bring telkens aan die lig dat Afrikaans sy amptelike gebruik grootliks prysgegee het. Dit is naamlik die aanwending van taal vir die doel van (1) (nasionale) wetgewing; (2) die amptelike notulering van hofverrigtinge; (3) staatsadministrasie; (4) polisiëring; en (5) openbare onderwys. Die amptelike gebruik van Afrikaans en die ander amptelike tale het geswig voor die voorkeurgebruik van Engels as gevolg waarvan Engels wesenlik Suid-Afrika se enigste daadwerklik amptelike taal geword het. Die deurslaggewende rede hiervoor is die huidige regering se politiek van transformatisme, veral aangedryf deur die beginsel van verteenwoordigendheid. Hierdie toedrag van sake is juridies moontlik gemaak deur die treff end diskresionêre aard van die ampteliketaalbepalings vervat in artikel 6 van die Grondwet. Die bepalings word transformatief vertolk en het tot ’n wesenlik eentalig Engelse ampteliketaalbedeling gelei. Hierdie verskynsel strook met wat elders in Sub-Sahara-Afrika gebeur het waar die eertydse postkoloniale administrasies telkens voorkeur gegee het aan die koloniale tale – Engels, Frans en Portugees – bo die Afrikatale. ENGLISH : The year 2025 marks a centenary of Afrikaans as one of South Africa’s official languages. From 2025 to 1994, it was one of the then two official languages; since 1994, one of eleven, and following the addition of sign language in 2023, one of twelve. However, there is scant reason for any cheerful festivities for Afrikaans’s “hundredth birthday”. The mere fact that section 6(1) of the present (1996) Constitution confirms the official status of Afrikaans should, for two reasons, not necessarily inspire elation. First, official status is in itself often of no moment; and secondly, constitutional provisions may, following the way they are interpreted and applied, simply lapse and/or be replaced by another official language regime. What emerges from these scenarios is that the relevant constitutional provisions exist only in name. Yet, in concrete terms, they lapse, being replaced by a new regime. This occurs notwithstanding there being no formal constitutional amendment in pursuance of the amendment provisions of the Constitution, and notwithstanding the Constitution’s swaggering claim of its own supremacy. We may describe this as lapsed and substituting the Constitution. It is precisely this kind of scenario that has played out in relation to Afrikaans as an official language in the present constitutional dispensation (since 1994). In the five most important fi elds of official language use, it has practically ceased to be an official language. These are the fi elds of (1) language use for national legislation; (2) language of record in court proceedings; (3) state administration; (4) policing; and (5) public education. Hence, although Afrikaans has nominally, under section 6 of the Constitution, retained its official status, in practical terms it has deteriorated to such an extent that it is not genuinely official anymore. If, in spite of this, it is nevertheless maintained that Afrikaans is an official language, it must be conceded that official status means no more than a symbolic proclamation. The juridical foundation for this course of events is the discretionary nature of the official language provisions, conferring on organs of the state responsible for implementing these provisions inordinately broad leeway to interpret the provisions as they deem fi t, more specifically, to conduct the interpretation and implementation in accordance with their ideological persuasions. The ideology driving the interpretation is that of transformationism (the national democratic revolution) perused by the post-1994 governing elite. This ideology emphatically favours the inculcation of one homogeneous statist culture, which favours a single previous colonial language – English in the case of South Africa – to the detriment of the other languages. For essentially similar reasons, developments elsewhere in post-colonial Sub-Saharan Africa have been strikingly similar. Most African states, like South Africa, are artificial creations of the erstwhile European colonial powers, and their boundaries resulted largely from the policies of these powers. Hence, in Africa, nations existed only in a territorial sense and not culturally or linguistically. Within these artificially created states, mostly devoid of the essential commonalities of nationhood, African governments must devise an official language policy. In the face of menacing centrifugal forces of inter-tribal, ethnic and accompanying linguistic tensions that could endanger the existence of African states, governments eschew the African languages that could unleash inter-communal strife. Instead, African governments opt for a tribally “neutral” European link-language which, in the face of the absence of commonalities, serves as a neutral ”nation builder”. Moreover, English provided the political vocabulary for resisting colonial domination and paving the way to political independence, something that the African languages were regarded as incapable of English (or any of the other colonial languages) was a prerequisite for leadership in Africa’s national movements. The elites of these movements are also basically English-speaking. This also holds true for the African National Congress (ANC) in South Africa, which is basically an English-speaking movement, or at least a movement led by an English-speaking elite. In this regard, there is a fundamental difference between national political consciousness in Africa and Europe. European national consciousness is essentially linguistic. The national consciousness of many of the communities was kindled by awareness of the national language in question, its perceived splendour and its expressive abilities, and the accompanying development of the literature of the various languages. The same holds true for Afrikaner nationalism. By contrast, African nationalism does not have a linguistic basis. They are, rather, anti-colonial. They dare not emphasise any particular African language and its development because that would place the state in danger of being split up along communal lines. Regarding language use, the foremost trend in education among black parents and pupils in South Africa has been to embrace English from the earliest possible stage. Even though educationists are unanimous that children perform best when instructed in the mother tongue, black parents are equally unanimous in rejecting that opinion. The trend elsewhere in previous British dominions in Africa is the same. If no African lingua franca is available, the only suitable course to take is a ”straight-for-English” approach, especially if parents see English as a prerequisite for their children’s socioeconomic advancement and press the school authorities to start education with English as the medium of instruction as early as possible. After 1994, when the African National Congress assumed power in South Africa, the trend in the education of African children slanted even more strongly towards English. These forces in favour of English are redoubtable, especially if the official language clause in the Constitution is discretionary, facilitating the drive towards a single-medium English dispensation.
CTX-M-producing Escherichia coli : history, molecular epidemiology and laboratory detection
Peirano, Gisele; Endimiani, Andrea; Pitout, Johann D.D. (Dove Medical Press, 2025-12-10)
From being a curiosity in the 1990s, CTX-M-producing Escherichia coli invaded most parts of the globe during the 2000s and 2010s, with multidrug-resistant (MDR) clone ST131 and CTX-M-15 leading the charge. The most widely distributed CTX-M types, with the highest global frequencies (up to 70% in certain lower- and middle-income countries), are CTX-M-15, CTX-M-14 and CTX-M-27. E. coli isolates with bla CTX-M-27 are currently emerging globally. The worldwide ascendancy of E. coli with bla CTX-M genes occurred via the spread of IncF plasmids between isolates and the existence of certain successful clones (eg, ST131) that acted as repositories for these genes. This is an impressive "gene survival strategy" that aided with the endurance of bla CTX-M in different environments, including the community and hospitals. The detection of extended-spectrum β-lactamase (ESBL)-producing E. coli (including CTX-M isolates) in clinical laboratories is reasonably straightforward. However, different methodologies (eg, immunogenic and genomic) have recently become available to specifically identify CTX-Ms in bacterial isolates as well as human specimens. The role of such tests is currently unclear. E. coli with CTX-M β-lactamases have indirectly been driving the carbapenemase pandemic and are forces to be reckoned with.
Does institutional quality matter in the interplay between corporate governance and firm performance? Lessons from South African financial firms
Ojeyinka, Titus Ayobami; Matemane, Matwale Reon (Sage, 2025-12)
The study investigates the effect of institutional quality on the corporate governance–firm performance nexus across 39 listed financial firms in South Africa via annual data from 2015 to 2022. We apply Driscoll and Kraay’s (1998) robust standard error and generalised method of moment estimation techniques to correct for cross-sectional dependence, serial correlation and endogeneity issues in this study. The study reveals a substantial positive correlation between firm performance and corporate governance metrics, including gender diversity, ethnic diversity, board size and board independence. This implies that having a large, independent, genderbased and ethnically diverse board improves company performance. In addition, all the indicators of institutional quality are found to enhance firm performance, while the relationship between corporate governance and firm performance in the industry is found to be strongly and negatively moderated by institutional quality. This suggests that corporate governance has a favourable impact on financial performance, but poor institutional quality weakens the beneficial and enhancing effects of corporate governance on firm performance. This research offers new insights into the importance of institutional frameworks and national governance mechanisms on the nexus between corporate governance and financial performance in the financial industry in South Africa.