Open AccessBurkholderia pseudomallei, the causative agent of melioidosis, is rare but ecologically established and widely dispersed in the environment in Puerto Rico
Author(s) -
Carina M. Hall,
Sierra A Jaramillo,
Rebecca E. Jimenez,
Nathan E. Stone,
Heather Centner,
Joseph D. Busch,
Nicole Bratsch,
Chandler C. Roe,
Jay E. Gee,
Alex R. Hoffmaster,
Sarai Rivera-Garcia,
Fred Soltero,
Kyle Ryff,
Janice Pérez-Padilla,
Paul Keim,
Jason W. Sahl,
David M. Wagner
Publication year - 2019
Publication title -
plos neglected tropical diseases
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.99
H-Index - 135
eISSN - 1935-2735
pISSN - 1935-2727
DOI - 10.1371/journal.pntd.0007727
Subject(s) - burkholderia pseudomallei , melioidosis , biology , clade , burkholderia , microbiology and biotechnology , phylogenetic tree , bacteria , gene , genetics
Background Burkholderia pseudomallei is a soil-dwelling bacterium and the causative agent of melioidosis. The global burden and distribution of melioidosis is poorly understood, including in the Caribbean. B . pseudomallei was previously isolated from humans and soil in eastern Puerto Rico but the abundance and distribution of B . pseudomallei in Puerto Rico as a whole has not been thoroughly investigated. Methodology/Principal findings We collected 600 environmental samples (500 soil and 100 water) from 60 sites around Puerto Rico. We identified B . pseudomallei by isolating it via culturing and/or using PCR to detect its DNA within complex DNA extracts. Only three adjacent soil samples from one site were positive for B . pseudomallei with PCR; we obtained 55 isolates from two of these samples. The 55 B . pseudomallei isolates exhibited fine-scale variation in the core genome and contained four novel genomic islands. Phylogenetic analyses grouped Puerto Rico B . pseudomallei isolates into a monophyletic clade containing other Caribbean isolates, which was nested inside a larger clade containing all isolates from Central/South America. Other Burkholderia species were commonly observed in Puerto Rico; we cultured 129 isolates from multiple soil and water samples collected at numerous sites around Puerto Rico, including representatives of B . anthina , B . cenocepacia , B . cepacia , B . contaminans , B . glumae , B . seminalis , B . stagnalis , B . ubonensis , and several unidentified novel Burkholderia spp. Conclusions/Significance B . pseudomallei was only detected in three soil samples collected at one site in north central Puerto Rico with only two of those samples yielding isolates. All previous human and environmental B . pseudomallei isolates were obtained from eastern Puerto Rico. These findings suggest B . pseudomallei is ecologically established and widely dispersed in the environment in Puerto Rico but rare. Phylogeographic patterns suggest the source of B . pseudomallei populations in Puerto Rico and elsewhere in the Caribbean may have been Central or South America.