A Review on Salmonella Characteristics, Taxonomy, Nomenclature with Special Reference to Non-Typhoidal and Typhoidal Salmonellosis

Document Type : Review Article


1 Department of Veterinary Public Health and Preventive Medicine, University of Ilorin 234, Nigeria

2 Department of Veterinary Public Health and Preventive Medicine, Ahmadu Bello University 234, Zaria, Nigeria

3 OIE Salmonella Reference Laboratory, National Microbiology Laboratory, Public Health Agency of Canada, Guelph, ON N1G 3W, Canada

4 Salmonella Reference laboratory, Istituto Zooprofilattico Sperimentale delle Venezie Viale dell’Università, Legnaro (PD) 35020, Italy


The genus Salmonella belongs to family Enterobacteriaceae. They possess interesting phenotypic/genotypic characteristics, history and peculiar nomenclature compared to other bacteria within and outside the family. The organism causes typhoidal salmonellosis (TS) and non-typhoidal salmonellosis (NTS), which exhibit different syndromes in man and animals and is of public health importance worldwide. This study reviewed the characteristics, taxonomy, nomenclature and nature of Salmonella in addition to the overview of NTS and TS. Baseline data/information published in peer reviewed journals, textbooks and bulletins/articles of international regulatory bodies were used for the study. The collective data of the present study revealed that Salmonella is a 2-3 X 0.4-0.6 µm sized, a Gram-negative rod, non-spore producing, oxidase, indole, urease, lactose and sucrose negative, facultative anaerobic and a motile organism. The two Salmonella species, that exist, only differ in their 16S rDNA sequences although both species are related closely to Shigella and E. coli at 16S rDNA and 32S rDNA sequences. Salmonella species and genus names are italicized; while more recently, the first letter of the serotype’s name is capitalized, but the word is not written in italics. Salmonella is the cause of NTS and TS in man and animals presenting enteritis, septicaemia, abortion and meningitis. Salmonellosis outbreaks had been reported from food, food products of animal origin and animal contact settings with cross infection between humans and animals. The disease in different parts of the world is among the public health challenges that are most common with reported increased incidence of many serotypes. The organism’s role as a major aetiology of foodborne disease and septicaemia resulting in morbidity and mortality worldwide had been highlighted. Continuous research on Salmonella and salmonellosis should be carried out to contribute to the body of knowledge on the organism, disease and ultimately improvement of preventive/therapeutic strategies of the disease. 


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