Clinical relevance of Salmonella enterica isolated from water and food in Eritrea

Dissertation (MSc (Microbiology))--University of Pretoria, 2007.

A total of 94 Salmonella isolates were collected from three catchments areas in Eritrea. These isolates were recovered from clinical and environmental sources. Biochemical tests using gelatin hydrolysis and tartrate utilization test were employed to differentiate between Salmonellasubspecies. All Salmonellaisolates were identified as Salmonellasubspecies I and were then subjected to molecular characterization. Polymerase chain reaction (PCR) and amplified fragment length polymorphism (AFLP) were employed to identify and establish possible relationships between the clinical isolates and environmental sources. Two sets of oligonucleotide primers specific for genes from S. Typhimurium and S. Enteritidis were used for the PCR reaction. Of the 94 Salmonellaisolates characterized only 6 were S. Typhimurium strains. To type the Salmonellaisolates AFLP was used. Clustering the AFLP patterns using the un-weighed pair-group method using arithmetic means (UPGMA) revealed 15 clusters. Of the 94 Salmonellaisolates collected, 48 (51%) strains were serologically identified. These serotypes include, 21 SalmonellaEmek (43.7%), 19 SalmonellaHeidelberg (39.5%), 7 of the 13, 22, 23; z undetermined serotype (14.5%), and 2 SalmonellaTyphimurium strains (4.1%). The AFLP data in the present study indicated a possible relationship between the clinical isolates and those obtained from environmental sources.

Microbiology and Plant Pathology

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