title: African pouched rats for the detection of pulmonary tuberculosis in sputum samples.
abstract: METHODS
  Resource-limited settings in sub-Saharan African countries.
  
  
  OBJECTIVE
  To utilise African giant pouched rats (Cricetomys gambianus) for the diagnosis of tuberculosis (TB) in human sputum.
  
  
  METHODS
  A specially designed cage with 10 sniffing holes and cassette-carrier was used. The sputum samples were put in the sample cassette, containing 10 samples in line, placed under matching sniffing holes. Rats were trained to sniff each consecutive sample, and indicate TB positives by fixing their nose for 5 seconds at the sniffing hole. This behaviour was maintained by food reinforcement upon correct indications. A total of 3416 samples were used.
  
  
  RESULTS
  Of the 20 trained rats, 18 were able to discriminate positive from negative sputum samples, with average daily sensitivities ranging from 72% to 100%, and average daily false-positives ranging from 0.7% to 8.1%. The use of multiple rats significantly increased sensitivity and negative predictive value.
  
  
  CONCLUSIONS
  Utilising trained sniffer rats for TB detection is a potentially faster screening method and is at least as sensitive as smear microscopy. This method could therefore be suitable for active case finding, especially where large numbers of samples are to be analysed in resource-limited settings, to complement existing diagnostic techniques.
authors.affiliation: Anti-Persoonsmijnen Ontmijnende Product Ontwikelling (APOPO), Antwerp, Belgium. bart.weetjens@gmail.com
authors.forename: Bart Jan Christiane
authors.initials: BJ
authors.lastname: Weetjens
authors.forename: G F
authors.initials: GF
authors.lastname: Mgode
authors.forename: R S
authors.initials: RS
authors.lastname: Machang'u
authors.forename: R
authors.initials: R
authors.lastname: Kazwala
authors.forename: G
authors.initials: G
authors.lastname: Mfinanga
authors.forename: F
authors.initials: F
authors.lastname: Lwilla
authors.forename: C
authors.initials: C
authors.lastname: Cox
authors.forename: M
authors.initials: M
authors.lastname: Jubitana
authors.forename: H
authors.initials: H
authors.lastname: Kanyagha
authors.forename: R
authors.initials: R
authors.lastname: Mtandu
authors.forename: A
authors.initials: A
authors.lastname: Kahwa
authors.forename: J
authors.initials: J
authors.lastname: Mwessongo
authors.forename: G
authors.initials: G
authors.lastname: Makingi
authors.forename: S
authors.initials: S
authors.lastname: Mfaume
authors.forename: J
authors.initials: J
authors.lastname: Van Steenberge
authors.forename: N W
authors.initials: NW
authors.lastname: Beyene
authors.forename: M
authors.initials: M
authors.lastname: Billet
authors.forename: R
authors.initials: R
authors.lastname: Verhagen
mesh_terms: D000818:Animals; D019937:Diagnostic Techniques and Procedures; D006801:Humans; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D012903:Smell; D013183:Sputum; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis*