Prevalence of Serratia Species Isolated from Children with Diarrhea and Studying their Virulence Factors

The aim of the current study is to find out the prevalence of Serratia species in stool samples of diarrheal cases in children less than five years old in Kirkuk City. In addition to study the virulence factors produced by the isolates under investigation. Patients and methods: Four hundred and seventy six stool samples were collected from children under five years with diarrhea during 1st of June 2016 to end of August 2018. The collected samples were cultured directly on different types of media for primary isolation of the Enterobacteriaceae then the suspicious colonies were selected for definitive microscopic examination, culture characteristics, biochemical testing and API 20E System for identifying Serratia species. Later the virulence factors for Serratia isolates were investigated. The results showed 10 (2.1%) isolates of Serratia species. were recovered, which were distributed as follow; 4 (0.8%) belonged to S. marcescens, in which only 1(0.2%) isolate was pigmented S. marcescens, 4 (0.8%) were S. liquifacience and 2 (0.4%) belonged to S. rubidea. The results showed that the distribution of the virulence factors were differ among the tested isolates. All the ten isolates (100%) were siderophores producers. Moreover, all S. marcescens isolates were able to produce, gelatinase, DNase, licithinase.