title: African 1, an epidemiologically important clonal complex of Mycobacterium bovis dominant in Mali, Nigeria, Cameroon, and Chad.
abstract: We have identified a clonal complex of Mycobacterium bovis present at high frequency in cattle in population samples from several sub-Saharan west-central African countries. This closely related group of bacteria is defined by a specific chromosomal deletion (RDAf1) and can be identified by the absence of spacer 30 in the standard spoligotype typing scheme. We have named this group of strains the African 1 (Af1) clonal complex and have defined the spoligotype signature of this clonal complex as being the same as the M. bovis BCG vaccine strain but with the deletion of spacer 30. Strains of the Af1 clonal complex were found at high frequency in population samples of M. bovis from cattle in Mali, Cameroon, Nigeria, and Chad, and using a combination of variable-number tandem repeat typing and spoligotyping, we show that the population of M. bovis in each of these countries is distinct, suggesting that the recent mixing of strains between countries is not common in this area of Africa. Strains with the Af1-specific deletion (RDAf1) were not identified in M. bovis isolates from Algeria, Burundi, Ethiopia, Madagascar, Mozambique, South Africa, Tanzania, and Uganda. Furthermore, the spoligotype signature of the Af1 clonal complex has not been identified in population samples of bovine tuberculosis from Europe, Iran, and South America. These observations suggest that the Af1 clonal complex is geographically localized, albeit to several African countries, and we suggest that the dominance of the clonal complex in this region is the result of an original introduction into cows naïve to bovine tuberculosis.
authors.affiliation: Swiss Tropical Institute, Socinstrasse 57, 4002 Basel, Switzerland.
authors.forename: Borna
authors.initials: B
authors.lastname: Müller
authors.forename: Markus
authors.initials: M
authors.lastname: Hilty
authors.forename: Stefan
authors.initials: S
authors.lastname: Berg
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Garcia-Pelayo
authors.forename: James
authors.initials: J
authors.lastname: Dale
authors.forename: M Laura
authors.initials: ML
authors.lastname: Boschiroli
authors.forename: Simeon
authors.initials: S
authors.lastname: Cadmus
authors.forename: Bongo Naré Richard
authors.initials: BN
authors.lastname: Ngandolo
authors.forename: Sylvain
authors.initials: S
authors.lastname: Godreuil
authors.forename: Colette
authors.initials: C
authors.lastname: Diguimbaye-Djaibé
authors.forename: Rudovick
authors.initials: R
authors.lastname: Kazwala
authors.forename: Bassirou
authors.initials: B
authors.lastname: Bonfoh
authors.forename: Betty M
authors.initials: BM
authors.lastname: Njanpop-Lafourcade
authors.forename: Naima
authors.initials: N
authors.lastname: Sahraoui
authors.forename: Djamel
authors.initials: D
authors.lastname: Guetarni
authors.forename: Abraham
authors.initials: A
authors.lastname: Aseffa
authors.forename: Meseret H
authors.initials: MH
authors.lastname: Mekonnen
authors.forename: Voahangy Rasolofo
authors.initials: VR
authors.lastname: Razanamparany
authors.forename: Herimanana
authors.initials: H
authors.lastname: Ramarokoto
authors.forename: Berit
authors.initials: B
authors.lastname: Djønne
authors.forename: James
authors.initials: J
authors.lastname: Oloya
authors.forename: Adelina
authors.initials: A
authors.lastname: Machado
authors.forename: Custodia
authors.initials: C
authors.lastname: Mucavele
authors.forename: Eystein
authors.initials: E
authors.lastname: Skjerve
authors.forename: Francoise
authors.initials: F
authors.lastname: Portaels
authors.forename: Leen
authors.initials: L
authors.lastname: Rigouts
authors.forename: Anita
authors.initials: A
authors.lastname: Michel
authors.forename: Annélle
authors.initials: A
authors.lastname: Müller
authors.forename: Gunilla
authors.initials: G
authors.lastname: Källenius
authors.forename: Paul D
authors.initials: PD
authors.lastname: van Helden
authors.forename: R Glyn
authors.initials: RG
authors.lastname: Hewinson
authors.forename: Jakob
authors.initials: J
authors.lastname: Zinsstag
authors.forename: Stephen V
authors.initials: SV
authors.lastname: Gordon
authors.forename: Noel H
authors.initials: NH
authors.lastname: Smith
mesh_terms: D000349:Africa / Q000453:epidemiology; D000818:Animals; D015373:Bacterial Typing Techniques; D002417:Cattle; D002872:Chromosome Deletion; D008969:Molecular Sequence Data; D009163:Mycobacterium bovis / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D014380:Tuberculosis, Bovine / Q000453:epidemiology* / Q000382:microbiology*