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Salmonella is a ubiquitous organism of public health importance that causes diarrhea and other systemic disease syndromes. The ecology and epidemiology of the organism in addition to the roles played by wild animals are important in understanding its disease. Relevant published peer-reviewed literature was obtained after imputing the study's keywords into the Google search engine. The publications were thereafter saved for the study. The study revealed the ecology of Salmonella is directly related to its epidemiology. These were found to be either positively or negatively influenced by the living and non-living parts of the environment. Free-ranging and captive wild animals can serve as asymptomatic carriers of Salmonella, therefore, help to maintain the cycle of the disease since wildlife serves as reservoir hosts to over 70% of emerging zoonotic diseases. Cockroaches transmit Salmonella through their feces, and body parts and when ingested by birds and animals. The statistically significant over 83% of Salmonella isolation in lizards suggests the reptile could be a source of Salmonella distribution. Snakes, foxes, badgers, rodents, and raccoons have been reported to have Salmonella as a natural component of their gut with the ability to shed the organism often. The high occurrence (>45%) of diverse Salmonella serovars coupled with the fact that some of these animals were handled, kept as pets and consumed by man portends these animals as potential sources of transmission of the organism and the disease. The etiology and epidemiology of Salmonella are overtly affected by several environmental factors which also determine their survival and maintenance. The roles played by wild animals in the relationship, transmission, growth or interaction within and between Salmonella spp., the occurrence, prevalence, and distribution of the organism help maintain the organism in the environment. An understanding of the roles played by the different parts of the environment and wild animals in the ecology and epidemiology of Salmonella can help make informed decisions on the prevention and control of the diseases it causes. This review aimed to investigate the relationship between ecology, epidemiology, and environment, including the roles played by wild animals in the maintenance of the organism and its disease.

Adherence to the guidelines of The International Organization for Standardization (ISO) for the isolation of Salmonella from faeces is important to laboratory personnel, researchers and epidemiologists to ensure effective diagnosis, maximal recovery and high sensitivity/specificity of laboratory tests. The aim of this study is to review the ISO guidelines for the detection of Salmonella from faeces using standards published by ISO and other internationally recognized bodies. The ISO 6579 of 2002 described the process for the detection of Salmonella in faeces. About 25g of faecal samples is collected, mixed together and specimen taken from different parts to ensure maximum recovery of the organism. Processes for the identification of the organism were prescribed by the standard. In the amendment made to ISO 6579 (Annex D) it was recommended that Modified Semisolid Rappaport Vasiliadis (MSRV) be used as selective enrichment medium. Further amendment made to this standard was in 2007 where clause 4 described non-selective pre-enrichment, selective enrichment, use of 2 selective solid media and biochemical tests as the 4 stages of the isolation of Salmonella in faeces. The amendment of ISO 6579 in 2017 combined the guidelines for the isolation of Salmonella species, S. Typhi/Paratyphi from milk/milk-products and faeces. It proposed the use of selenite cysteine broth in addition to Rappaport Vasiliadis (RVS) and Muller-Kauffmann Tetrathionate-Novobiocin (MkTTn) and BSA in addition to Xylose Lysine Deoxycholate (XLD) Agar for the isolation of S. typhi and paratyphi. It recommended the performance of methyl-red, Simmoncitrate, H2S, motility and urease biochemical tests, deleted Vogues Proskaer test while indole and ß-Galactosidase (ONPG) tests were made optional. This standard has evolved over the years to ensure efficient recovery of Salmonella from faeces based on real-time result and feedback received by the organization from laboratories all over the world. [ABSTRACT FROM AUTHOR]