Pathogenicity, genotyping and antibacterial susceptibility of the Listeria spp. recovered from stray dogs

Overview of listeriosis in the Southern African Hemisphere—Review

“…fleischmannii , and L . newyorkensis (Abay et al, ; Barre et al, ; Bertsch et al, ; Weller, Andrus, Wiedmann, & Bakker, ). These 11 new Listeria species were regarded to be non‐pathogenic to humans on the basis of not having major genetic traits in their genomic elements hence; Listeria genus currently has 17 species (Orsi & Wiedmann, ).…”

“…Listeria may also be found in processed foods due to chances of contamination that may occur after processing or when inadequate heat treatment is used (US FDA, ). Domestic as well as wild mammals like: fowls, sheep, dog, and cattle are popularly known reservoirs of this pathogen (Abay et al, ). Humans most especially abattoir and laboratory workers may also be asymptomatic fecal carriers of these pathogens (Heymann, ).…”

“…Consequently, they can proliferate in contaminated foods during refrigeration (US FDA, ). Listeria can grow in diverse environments with conditions like low pH, low water activity, and high salinity (Abay et al, ; Ghanbari, Jami, Domig, & Kneifel, ; Jami et al, ). However, they can be easily destroyed at cooking temperatures (Chan & Wiedmann, ).…”

“…However, they can also be transmitted between humans (from mother to fetus both in peripartum and utero following maternal bacteremia). Other uncommon possible modes include infected animals to humans resulting in skin lesions among veterinarians and nosocomial transmission (Abay et al, ; Goenka & Kneen, ; Nelson, Warren, Tomasi, Raju, & Vidyasagar, ). Transmission of Listeria from animal to human and its circulation in the environment is presented in Figure .…”

“…The virulence expressed by strains of this species may be dependent on serotype, with serotypes ½a, ½c, ½b, and 4b in most cases implicated in cases of human listeriosis (Abay et al, ; Kathariou, ) among these; serotypes ½a, ½b, and 4b are mostly clinical isolates. Most strains of the serotype 4b (not commonly found in food) have been reported in cases of major invasive listeriosis outbreaks and serovar ½a strains in sporadic listeriosis outbreak (Kathariou, ; Muchaamba et al, ).…”