title: Occurrence of Listeria spp. in retail meat and dairy products in the area of Addis Ababa, Ethiopia.
abstract: BACKGROUND
  Listeriosis, a bacterial disease in humans and animals, is mostly caused by ingestion of Listeria monocytogenes via contaminated food and/or water, or by a zoonotic infection. Globally, listeriosis has in general a low incidence but a high case fatality rate.
  
  
  OBJECTIVE
  The objective of this study was to investigate the occurrence, antimicrobial profiles, and genetic relatedness of L. monocytogenes from raw meat and dairy products (raw milk, cottage cheese, cream cake), collected from the capital and five neighboring towns in Ethiopia.
  
  
  METHODS
  Two hundred forty food samples were purchased from July to December 2006 from food vendors, shops, and supermarkets, using a cross-sectional study design. L. monocytogenes were isolated and subjected to molecular serotyping. The genetic relatedness and antimicrobial susceptibility patterns were investigated using pulsed-field gel electrophoresis (PFGE) and minimum inhibitory concentration determinations.
  
  
  RESULTS
  Of 240 food samples tested, 66 (27.5%) were positive for Listeria species. Of 59 viable isolates, 10 (4.1%) were L. monocytogenes. Nine were serotype 4b and one was 2b. Minimum inhibitory concentration determination and PFGE of the 10 L. monocytogenes isolates showed low occurrence of antimicrobial resistance among eight different PFGE types.
  
  
  CONCLUSIONS
  The findings in this study correspond to similar research undertaken in Ethiopia by detecting L. monocytogenes with similar prevalence rates. Public education is crucial as regards the nature of this organism and relevant prevention measures. Moreover, further research in clinical samples should be carried out to estimate the prevalence and carrier rate in humans, and future investigations on foodborne outbreaks must include L. monocytogenes.
authors.affiliation: Food Microbiology Section, Food Science and Nutrition Research Directorate, Ethiopian Health and Nutrition Research Institute, Addis Ababa, Ethiopia. firehiwot_a@yahoo.com
authors.forename: Firehiwot Abera
authors.initials: FA
authors.lastname: Derra
authors.forename: Susanne
authors.initials: S
authors.lastname: Karlsmose
authors.forename: Dharam P
authors.initials: DP
authors.lastname: Monga
authors.forename: Abebe
authors.initials: A
authors.lastname: Mache
authors.forename: Christina Aaby
authors.initials: CA
authors.lastname: Svendsen
authors.forename: Benjamin
authors.initials: B
authors.lastname: Félix
authors.forename: Sophie A
authors.initials: SA
authors.lastname: Granier
authors.forename: Abera
authors.initials: A
authors.lastname: Geyid
authors.forename: Girum
authors.initials: G
authors.lastname: Taye
authors.forename: Rene S
authors.initials: RS
authors.lastname: Hendriksen
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D003611:Dairy Products / Q000191:economics / Q000382:microbiology*; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D005002:Ethiopia; D008087:Listeria / Q000145:classification / Q000187:drug effects / Q000254:growth & development* / Q000302:isolation & purification; D008089:Listeria monocytogenes / Q000145:classification / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D008460:Meat / Q000191:economics / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D008892:Milk / Q000191:economics / Q000382:microbiology; D058889:Molecular Typing; D014507:Urbanization
chemical_list: D000900:Anti-Bacterial Agents