title: A retrospective epidemiological study on the incidence of salmonellosis in the State of Qatar during 2004-2012.
abstract: BACKGROUND
  Salmonella is a food- and water-borne pathogen that can be easily spread in a population, leading to the outbreak of salmonellosis that is caused by ingestion of mixed salads contaminated by the pathogen. Most cases occur in the late spring months and can be seen as single cases, clusters, or episodes.
  
  
  OBJECTIVE
  The aim of this study was to describe the incidence and epidemiological characteristics of salmonellosis in the State of Qatar.
  
  
  METHODS
  This was a retrospective, descriptive study carried out in laboratory-confirmed cases of salmonellosis during 2004-2012 from all Salmonella surveillance centers. Therapeutic records of patients who were clinically suspected of having Salmonella diseases were analyzed. Initially, cases with typhoid fever were investigated in the laboratory by means of Widal agglutination tests, while non-typhoidal Salmonella diseases were determined based on culture technique.
  
  
  RESULTS
  The annual incident of salmonellosis cases were 12.3, 23.0, 30.3, 19.4, 15.3, 18.0, 22.7, 18.5, and 18.1 per 100,000 population in 2006-2011 and 2012, respectively. The number of salmonellosis cases was high among less than 2-year-old females and 3-year-old males. In addition, one-fourth of patients (27.7%) were Qatari when compared to other nationalities. A significant difference in age was found between Qatari (6.08 ± 12.28 years) and non-Qatari (15.04 ± 19.56 years) patients. Of the reported cases, 79.8% included the onset date of the first symptoms. Contact phone numbers were available for 94% of the cases but addresses were available for only 50.4% of cases. The time difference between onset of symptoms and diagnosis was 5.4 ± 5.7 days. The most frequent serotype reported were type b (41.9%), type d (26.9%), and type c1 (12.2%).
  
  
  CONCLUSIONS
  The present surveillance data showed a high incidence of salmonellosis in Qatar that poses a serious public health problem. Special intervention and health awareness programs are required for early screening, detection, and treatment as well as for strengthening the surveillance system of salmonellosis, with special emphasis on the laboratory study of cases.
authors.affiliation: Department of Public Health, Ministry of Public Health, Doha, Qatar.
authors.forename: Elmoubasher
authors.initials: E
authors.lastname: Farag
authors.affiliation: The Cuban Hospital, Hamad Medical Corporation, Dukhan, Qatar.
authors.forename: Humberto Guanche
authors.initials: HG
authors.lastname: Garcell
authors.affiliation: Department of Public Health, Ministry of Public Health, Doha, Qatar.
authors.forename: Nandakumar
authors.initials: N
authors.lastname: Ganesan
authors.affiliation: Department of Public Health, Ministry of Public Health, Doha, Qatar.
authors.forename: Shazia Nadeem N
authors.initials: SN
authors.lastname: Ahmed
authors.affiliation: Department of Public Health, Ministry of Public Health, Doha, Qatar.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Al-Hajri
authors.affiliation: Department of Public Health, Ministry of Public Health, Doha, Qatar.
authors.forename: Shk Mohammed Hamad J
authors.initials: SM
authors.lastname: Al Thani
authors.affiliation: Department of Public Health, Ministry of Public Health, Doha, Qatar.
authors.forename: Salih Ali
authors.initials: SA
authors.lastname: Al-Marri
authors.affiliation: Department of Laboratory Medicine and Pathology, Hamad Medical Corporation, Doha, Qatar.
authors.forename: Emad
authors.initials: E
authors.lastname: Ibrahim
authors.affiliation: Department of Public Health, Ministry of Public Health, Doha, Qatar.
authors.forename: Hamad Eid
authors.initials: HE
authors.lastname: Al-Romaihi
keywords: Qatar; Salmonella surveillance; food- and water-borne pathogen; incidence rates