Received: 21 August 2019 Revised: 12 October 2019 Accepted: 19 October 2019 DOI: 10.1111/jfs.12732 ORIGINAL ARTICLE Overview of listeriosis in the Southern African Hemisphere—Review Adeoye J. Kayode1,2 | Etinosa O. Igbinosa3 | Anthony I. Okoh1,2 1Applied and Environmental Microbiology Research Group (AEMREG), Department of Abstract Biochemistry and Microbiology, University of Listeriosis is rarely reported in the Southern African Hemispheres in spite of the Fort Hare, Alice, South Africa increasing rate of Listeria in several foodborne outbreaks reported in advanced coun- 2SAMRC Microbial Water Quality Monitoring Center, University of Fort Hare, Alice, tries. This paper reviews the emerging trends in the spread, distribution, and epidemi- South Africa ology of Listeria species in foods, water, human, animals, and different environments 3Department of Microbiology, Faculty of Life Sciences, Private Mail Bag 1154, University of in Southern Africa based on the appraisal of scholarly articles. In this regard, informa- Benin, Benin City, Nigeria tion obtained from literatures from various online databases revealed that Listeria Correspondence species are commonly recovered from food, water, and human samples. Fewer arti- Adeoye J. Kayode, Applied and Environmental cles provided information on Listeria recovered from animals (ruminants) and soil Microbiology Research Group (AEMREG), Department of Biochemistry and samples. Generally, reports of studies were more focused on Listeria monocytogenes Microbiology, University of Fort Hare, Private among other Listeria species. To this end, reports obtained from literature on the Mail Bag X1314, Alice 5700, South Africa. Email: [email protected] method of identification of Listeria were mostly based on serological, classical bio- chemical methods and the principle of aesculin hydrolysis, usually characterized by Funding information The World Academy of Sciences, Grant/Award black coloration on selective media for Listeria. These methods may not be reliable, Number: 110811; National Research as they could sometimes give a false positive report. Therefore, molecular methods Foundation of South Africa; South African Medical Research Council are more reliable, accurate, could show the genetic relationship between isolates, and at the same time capable of enabling tracking the source of this pathogen should be embraced as a better substitute for the identification of Listeria in Southern African sub-region. 1 | INTRODUCTION that they are catalase positive, oxidase negative, and ferment carbohydrates (Orsi & Wiedmann, 2016; Rods, 2014). Listeria is a bacterial genus, of the family Listeriaceae, made up of Listeria genus used to composed of six species which are: L. mono- gram-positive members that are short rods with a round end (Orsi & cytogenes, L. ivanovii, L. seeligeri, L. grayi, L. welshimeri, and L. innocua; Wiedmann, 2016). Usually, they appear as singular cells, short chains, all of which are mostly adapted to water, soil, and vegetation (Hawker and sometimes filamentous (Gelfand, 2012; Rods, 2014). They are fac- et al., 2018; Linke et al., 2014). Recently, a subspecies, and novel ultative anaerobes (Bortolussi, 2008), non-acid fast bacteria, non- species, usually isolated from foods, environmental niches in spore forming, and without capsule (Sleator, Watson, Hill, & Gahan, different parts of the world, as well as the natural and agricultural 2009). Listeria species possess peritrichous flagella, which are respon- milieu, were introduced to the genus, and includes: L. marthii, L. sible for their typical “tumbling” motility when grown at 20 to 25C weihenstephanensis, L. booriae, L. fleischmannii subsp. coloradonensis; (Rods, 2014). When cultivated on blood agar, the colonies are non- novel species such as L. floridensis, L. aquatica L. cornellensis, L. pigmented and may show resemblance to those of β-hemolytic strep- grandensis, L. riparia, L. fleischmannii, and L. newyorkensis (Abay et al., tococci (Gelfand, 2012). Their biochemical characteristics revealed 2019; Barre et al., 2016; Bertsch et al., 2013; Weller, Andrus, This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. © 2019 The Authors. Journal of Food Safety published by Wiley Periodicals, Inc. J Food Saf. 2020;40:e12732. wileyonlinelibrary.com/journal/jfs 1of22 https://doi.org/10.1111/jfs.12732 2of22 KAYODE ET AL. Wiedmann, & Bakker, 2015). These 11 new Listeria species were et al., 2019; Ghanbari, Jami, Domig, & Kneifel, 2013; Jami et al., regarded to be non-pathogenic to humans on the basis of not having 2014). However, they can be easily destroyed at cooking tempera- major genetic traits in their genomic elements hence; Listeria genus tures (Chan & Wiedmann, 2008). currently has 17 species (Orsi & Wiedmann, 2016). In spite of the increasing listeriosis rate reported in several foodborne outbreaks globally (Desai, Anyoha, Madoff, & Lassmann, 1.2 | Transmission of Listeria 2019; Siegman-Igra et al., 2002) such as Europe, Germany, France, Japan, New Zealand, U.S.A. (Botsaris, Nikolaou, Liapi, & Pipis, 2016; Transmission of Listeria spp. (80–90%) is primarily by (fecal-oral route) Halbedel et al., 2019; Marus, 2019), China (Wang et al., 2013), consuming contaminated foods and water (den Bakker, Manuel, Canada (Hanson et al., 2019), it is not commonly reported in the Fortes, Wiedmann, & Nightingale, 2013; Jarvis, O'Bryan, Ricke, John- Southern African hemisphere. This study articulates an overview of son, & Crandall, 2016; Linke et al., 2014). However, they can also be emerging trends in the spread, distribution, and epidemiology of transmitted between humans (from mother to fetus both in per- Listeria species in foods, water, human, animals, and different environ- ipartum and utero following maternal bacteremia). Other uncommon ments in the Southern African countries. This review, evaluates schol- possible modes include infected animals to humans resulting in skin arly articles obtained from various online databases such as Google lesions among veterinarians and nosocomial transmission (Abay et al., Scholar, Pubmed, and Scopus. The search keywords used to access 2019; Goenka & Kneen, 2019; Nelson, Warren, Tomasi, Raju, & articles online includes phrases such as “isolation of Listeria species, Vidyasagar, 1985). Transmission of Listeria from animal to human and Listeria species in Southern Africa, Listeriosis and global outbreaks.” its circulation in the environment is presented in Figure 1. Search keywords like “Listeria species in South Africa” Listeria species The disease conditions associated with Listeria infection could be in Angola” and so on were also employed to source for articles for categorized into non-invasive (febrile listerial gastroenteritis) and inva- each of the Southern African countries (Angola, Botswana, Lesotho, sive (infection caused at sterile part of the body such as the blood, Malawi, Namibia, South Africa, Swaziland, Zambia, and Zimbabwe). liver, cerebral fluid) listeriosis (Bhat et al., 2013; Data, 2015; Zhu, Goo- Searches were extended to source for more articles on Google, due to neratne, & Hussain, 2017). Non-invasive listeriosis manifests less fewer articles indexed by the databases previously searched. There- severe symptoms like fever, diarrhea, headache, and muscle pain fore, this article further described the ecological distribution, transmis- (myalgia) which occur after a short incubation period and is often sion, treatment, control, and occurrence of Listeria of species in food, associated with ingestion of a high dose of the pathogenic Listeria food processing environment, water, animal, and human. species by healthy persons (FSAI, 2011; WHO, 2018) as reported in the case noninvasive listeriosis (Halbedel et al., 2019). Invasive listeri- osis affects immunosuppressed individual including cancer patients, 1.1 | Ecological distribution of Listeria pregnant women, acquired immunodeficiency syndrome (AIDS) patients, young and elderly persons (Desai et al., 2019). It is usually Species of Listeria have a wide distribution in the environment and have characterized by the severity of symptoms and high death rate com- been recovered from dust, vegetation, decaying materials, soil, water, monly associated with gastroenteritis, meningitis, pneumonia, septice- sewage, animal feeds, silage, and natural habitats (Barre et al., 2016; mia, and spontaneous abortion (Arslan & Baytur, 2019; Chersich, Sheng, Tsai, Zhu, & Zhu, 2019; Weller et al., 2015). They are often pre- Scorgie, Rees, & Wright, 2018; FSAI, 2011; Vázquez-Boland et al., sent in foods gotten from plant and animal sources, and are constantly 2001). The infectious dose of Listeria may vary with the susceptive found in environments where food is processed (Aalto-Araneda, host and the strain causing infection (FSAI, 2011; Pouillot et al., Lunden, Markkula, Hakola, & Korkeala, 2019; Kaczmarek, Avery, & Sin- 2016). The approximate value of 106–107 CFUs (colony forming units) gleton, 2019). Listeria may also be found in processed foods due to is considered as the infectious dose of L. monocytogenes in humans chances of contamination that may occur after processing or when and primates, however a lower dose of 104 can cause listeriosis in per- inadequate heat treatment is used (US FDA, 2019). Domestic as well as sons with compromised immune