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Volume 26, Number 9—September 2020
Research

Molecular Description of a Novel Orientia Species Causing Scrub Typhus in Chile

Katia AbarcaComments to Author , Constanza Martínez-Valdebenito1, Jenniffer Angulo1, Ju Jiang, Christina M. Farris, Allen L. Richards, Gerardo Acosta-Jamett, and Thomas WeitzelComments to Author 
Author affiliations: Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile (K. Abarca, C. Martínez-Valdebenito, J. Angulo); Naval Medical Research Center, Silver Spring, Maryland, USA (J. Jiang, C.M. Farris); Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA (A.L. Richards); Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile (G. Acosta-Jamett); Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago (T. Weitzel)

Main Article

Figure 1

Phylogenetic analyses of sequences of the 16S rRNA gene (rrs) from scrub typhus cases in Chile compared with those from different Orientia and Rickettsia species and other microorganisms. We inferred the evolutionary history by using the maximum-likelihood method based on the Kimura 2-parameter model (21), according to the Bayesian information criterion for these sequences. The analysis involved 39 nt sequences and a total of 875 positions in the final dataset. The trees is drawn to scale, with

Figure 1. Phylogenetic analyses of sequences of the 16S rRNA gene (rrs) from scrub typhus cases in Chile compared with those from different Orientia and Rickettsia species and other microorganisms. We inferred the evolutionary history by using the maximum-likelihood method based on the Kimura 2-parameter model (21), according to the Bayesian information criterion for these sequences. The analysis involved 39 nt sequences and a total of 875 positions in the final dataset. The trees is drawn to scale, with branch lengths measured in the number of substitutions per site. All positions containing gaps and missing data were eliminated. For isolates from the cases in this study, the suffix “M” indicates an origin in mainland Chile and “I” an origin on Chiloé Island; these isolates clustered into a proposed new species provisionally named Candidatus Orientia chiloensis. GenBank accession numbers are indicated for reference sequences. Scale bar indicates nucleotide divergence.

Main Article

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1These authors contributed equally to this article.

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