RESUMEN
The distribution of Borrelia burgdorferi sensu lato genospecies in questing Ixodes ricinus ticks from ecologically distinct habitats in Latvia was analyzed. A significant variation in the frequency of the genospecies across sites was observed, pointing to the importance of the host community in the ecology of Lyme borreliosis.
Asunto(s)
Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/aislamiento & purificación , Lipoproteínas , Alelos , Animales , Antígenos de Superficie/genética , Proteínas de la Membrana Bacteriana Externa/genética , Vacunas Bacterianas , Grupo Borrelia Burgdorferi/clasificación , Ambiente , Genes Bacterianos , Variación Genética , Ixodes/microbiología , Letonia , SerotipificaciónRESUMEN
The roles of selection and migration of B. burgdorferi s. l. were studied. Questing adult Ixodes ricinus ticks were collected across Europe and analysed for infection with B. burgdorferi s. l. Analysis of the genospecies in individual ticks showed that B. garinii and B. valaisiana segregate from B. afzelii. Segregation of bird- and rodent-associated Borrelia genotypes can be explained by the operation of complement-mediated selection in the midgut of the feeding tick. Phylogenetic analyses of B. burgdorferi s. l. indicate high rates of migration for bird-associated genotypes. Altogether, it is emerging that the ecology of Lyme borreliosis is largely host-driven and that selection and migration are major forces shaping the population structures of B. burgdorferi s. l.
Asunto(s)
Vectores Arácnidos/microbiología , Grupo Borrelia Burgdorferi/clasificación , Ixodes/microbiología , Enfermedad de Lyme/microbiología , Animales , Aves , Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/aislamiento & purificación , Transmisión de Enfermedad Infecciosa , Ecosistema , Europa (Continente) , Genotipo , Interacciones Huésped-Parásitos , Humanos , Enfermedad de Lyme/transmisión , Filogenia , RoedoresRESUMEN
Borrelia burgdorferi sensu lato (s.l.), the tick-borne agent of Lyme borreliosis, is a bacterial species complex comprising 11 genospecies. Here, we discuss whether the delineation of genospecies is ecologically relevant. We provide evidence that B. burgdorferi s.l. is structured ecologically into distinct clusters that are host specific. An immunological model for niche adaptation is proposed that suggests the operation of complement-mediated selection in the midgut of the feeding tick. We conclude that vertebrate hosts rather than tick species are the key to Lyme borreliosis spirochaete diversity.
