Occurrence, Serotypes and Virulence Characteristics of Shiga-Toxin-Producing Escherichia coli Isolates from Goats on Communal Rangeland in South Africa

Mogaugedi N Malahlela; Beniamino T Cenci-Goga; Munyaradzi C Marufu; Thierry Y Fonkui; Luca Grispoldi; Eric Etter; Alan Kalake; Musafiri Karama

doi:10.3390/toxins14050353

Occurrence, Serotypes and Virulence Characteristics of Shiga-Toxin-Producing Escherichia coli Isolates from Goats on Communal Rangeland in South Africa

Toxins (Basel). 2022 May 18;14(5):353. doi: 10.3390/toxins14050353.

Authors

Mogaugedi N Malahlela¹, Beniamino T Cenci-Goga^{1

2}, Munyaradzi C Marufu³, Thierry Y Fonkui¹, Luca Grispoldi², Eric Etter^{4

5

6}, Alan Kalake⁷, Musafiri Karama¹

Affiliations

¹ Veterinary Public Health Section, Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa.
² Departiment of Veterinary Medicine, Laboratorio di Ispezione Degli Alimenti di Origine Animale, University of Perugia, 06126 Perugia, Italy.
³ Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa.
⁴ Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort 0110, South Africa.
⁵ Centre de Coopération Internationale en Recherche Agronomique Pour le Développement (CIRAD), Unité Mixte de Recherche (UMR), Animal Santé, Territoires, Risques et Ecosystèmes (ASTRE), 97170 Petit Bourg, France.
⁶ ASTRE, University Montpellier, CIRAD, INRAE, France Baillarguet International Campus, University of Montpellier, 34070 Montpellier, France.
⁷ Gauteng Department of Agriculture and Rural Development, Johannesburg 2001, South Africa.

Abstract

Shiga-toxin-producing Escherichia coli is a foodborne pathogen commonly associated with human disease characterized by mild or bloody diarrhea hemorrhagic colitis and hemolytic uremic syndrome. This study investigated the occurrence of STEC in fecal samples of 289 goats in South Africa using microbiological culture and PCR. Furthermore, 628 goat STEC isolates were characterized by serotype (O:H) and major virulence factors by PCR. STEC was found in 80.2% (232/289) of goat fecal samples. Serotyping of 628 STEC isolates revealed 63 distinct serotypes including four of the major top seven STEC serogroups which were detected in 12.1% (35/289) of goats: O157:H7, 2.7% (8/289); O157:H8, 0.3%, (1/289); O157:H29, 0.3% (1/289); O103:H8, 7.6% (22/289); O103:H56, 0.3% (1/289); O26:H2, 0.3% (1/289); O111:H8, 0.3% (1/289) and 59 non-O157 STEC serotypes. Twenty-four of the sixty-three serotypes were previously associated with human disease. Virulence genes were distributed as follows: stx1, 60.6% (381/628); stx2, 72.7% (457/628); eaeA, 22.1% (139/628) and hlyA, 78.0% (490/628). Both stx1 and stx2 were found in 33.4% (210/628) of isolates. In conclusion, goats in South Africa are a reservoir and potential source of diverse STEC serotypes that are potentially virulent for humans. Further molecular characterization will be needed to fully assess the virulence potential of goat STEC isolates and their capacity to cause disease in humans.

Keywords: STEC; South Africa; goats; serotypes; virulence.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Animals
Goats
Serogroup
Shiga-Toxigenic Escherichia coli* / genetics
South Africa
Virulence

Grants and funding

This research was funded by the National Research Foundation (NRF) of South Africa (CSRP170528234222 and SARCHI COP Grant 120317) the South African Medical Research Council Self-Initiated Research (MRC/SIR 2017-2019), and UNICEF Future Africa-UP One Health for Change research grants-2021.