title: Prevalence and risk factors of bovine tuberculosis in dairy cattle in Eritrea.
abstract: BACKGROUND
  The prevalence of bovine tuberculosis (BTB) in dairy cattle in the three major milk producing regions of Eritrea was assessed by subjecting 15,354 dairy cattle, 50 % of Eritrea's dairy cattle population, to the single intradermal comparative tuberculin test (SICTT). Skin test results were interpreted according to guidelines of the World Organization for Animal Health (OIE) with >4 mm as cutoff in skin thickness increase. In addition, we studied the relation between 'physiological' variables related to pregnancy and lactation, and the variable 'region' on the probability to be skin test positive.
  
  
  RESULTS
  The BTB prevalences at animal and herd levels were: 21.5% and 40.9% in Maekel, 7.3% and 10% in Debub, and 0.2% and 1.6% in the Anseba region, respectively. Overall, in the regions included, prevalence was 11.3% (confidence interval (CI) 95% CI, 11.29 - 11.31%) and 17.3% (95% CI, 17.27-17.33%), at animal and herd level, respectively. Considering positive herds only, the animal BTB prevalence was 36.8%, 30.1%, and 1.8%, in Maekel, Debub and Anseba, respectively, and the overall animal prevalence within these herds was 32%. In adult dairy cattle the probability of positive reactivity in the SICTT test was highest in pregnant animals as compared to the other categories.
  
  
  CONCLUSIONS
  This study reports persistent prevalence of BTB as defined by positive SICTT in the dairy sector of Eritrea, especially in the regions of Maekel and Debub that are located in the central highlands of the country. To our understanding this is the first report that has encompassed all the major dairy farms in Eritrea and it will be instrumental in advocating future BTB control programs in the dairy sector.
authors.affiliation: Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands. michaelvet@yahoo.com.|Department of Veterinary Sciences, Hamelmalo Agricultural College, Keren, Eritrea. michaelvet@yahoo.com.
authors.forename: Michael K
authors.initials: MK
authors.lastname: Ghebremariam
authors.affiliation: Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.|Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa.
authors.forename: V P M G
authors.initials: VP
authors.lastname: Rutten
authors.affiliation: Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: J C M
authors.initials: JC
authors.lastname: Vernooij
authors.affiliation: Veterinary Services, Ministry of Agriculture (MOA), Mendefera, Debub Region, Eritrea.
authors.forename: K
authors.initials: K
authors.lastname: Uqbazghi
authors.affiliation: National Animal and Plant Health Laboratory, MOA, Asmara, Eritrea.
authors.forename: T
authors.initials: T
authors.lastname: Tesfaalem
authors.affiliation: Veterinary Services, MOA, Keren, Anseba Region, Eritrea.
authors.forename: T
authors.initials: T
authors.lastname: Butsuamlak
authors.affiliation: Veterinary Services, MOA, Asmara, Maekel Region, Eritrea.
authors.forename: A M
authors.initials: AM
authors.lastname: Idris
authors.affiliation: Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Nielen
authors.affiliation: Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria, South Africa.
authors.forename: A L
authors.initials: AL
authors.lastname: Michel
mesh_terms: D000818:Animals; D002417:Cattle; D003430:Cross-Sectional Studies; D003612:Dairying; D019017:Eritrea / Q000453:epidemiology; D005260:Female; D008297:Male; D012307:Risk Factors; D014380:Tuberculosis, Bovine / Q000453:epidemiology*
keywords: Bovine tuberculosis (BTB); Comparative tuberculin test; Dairy; Eritrea; Prevalence