For First Time, Organism Responsible For Buruli Ulcer Isolated And Characterized

The
organism that causes Buruli ulcer (BU) has, for the first time, been
isolated and characterized, according to an article published on March
26, 2008 in PLoS Neglected Tropical Diseases.



Buruli
ulcer is a neglected disease that necrotizes flesh and sometimes
produces enormous, disfiguring ulcers that have a high social impact on
the victim. It was previously postulated that the responsible agent is
the Mycobacterium ulcerans, and that transmission
to humans
occurs in aquatic areas. However, the method of transmission has not
actually been characterized, and the organism has never been isolated
in pure culture before from any environmental sources.



The Buruli ulcer often
presents itself in children in the humid, tropical, and impoverished
regions of rural Africa, but can affect many different types of
populations. Incidence has been steadily increasing, and it now affects
more people in certain regions than tuberculosis and leprosy, two other
diseases which have been shown to be caused by mycobacteria. It is a
disease that reinforces poverty, and is chronically infectious.



In this study, M. ulcerans
was isolated from the environment and characterized by Françoise
Portaels (Institute of Tropical Medicine, Antwerpen, Belgium) and
colleagues in Ghana, Portugal, and the US. To the best of their
knowledge, this is the first time that this task has been successfully
performed, and they provide the details in the given article.



To
isolate the bacterium, the team collected several aquatic specimens
that were targeted for the study of mycobacteria in BU endemic regions
in Benin and Togo. In vitro cultures were
established and analyzed using PCR and by inoculating the organism in
mice.



The resulting isolated strain has features similar to the
microbiological characteristics of African strains of Mycobacterium
ulcerans,
and was found in an aquatic insect called the Water Strider. Further
analysis lends support to the idea that the organism is transmitted to
humans from aquatic niches and not directly from person to person. "Our
findings support the concept that Mycobacterium ulcerans is a pathogen
of humans with an aquatic environmental niche," state the authors. They
further indicate that this result "will have positive consequences for
the control of this neglected and socially important tropical disease."



Tim
Stinear (Monash University, Clayton, Victoria, Australia) and Paul
Johnson (Austin Hospital, Heidelberg, Australia), who were not involved
in the study, contributed an Expert Commentary in the same issue
of PLoS Neglected Tropical Diseases. They
reinforce that
this new study is a true breakthrough in the study of this debilitating
disease.  "[It is a] a major achievement and will serve as the
definitive reference point for scientists' intent on revealing the
ecology, environmental reservoir, and precise mode of transmission of
Mycobacterium ulcerans.



About PLoS Neglected Tropical Diseases



PLoS Neglected Tropical Diseases (plosntds/)
is a peer-reviewed, open-access journal devoted to the pathology,
epidemiology, prevention, treatment, and control of the neglected
tropical diseases, as well as public policy relevant to this group of
diseases. All works published in PLoS Neglected Tropical
Diseases
are open access, which means that everything is immediately and freely
available subject only to the condition that the original authorship
and source are properly attributed. The Public Library of Science uses
the Creative Commons Attribution License, and copyright is retained by
the authors.



About the Public Library of Science



The
Public Library of Science (PLoS) is a non-profit organization of
scientists and physicians committed to making the world's scientific
and medical literature a freely available public resource. For more
information, visit plos.



First Cultivation and Characterization of Mycobacterium
ulcerans from the Environment.

Portaels F, Meyers WM, Ablordey A, Castro AG, Chemlal K, et al.

PLoS Negl Trop Dis 2(3): e178.

doi:10.1371/journal.pntd.0000178

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Here For Full Length



First Isolation of Mycobacterium ulcerans from an Aquatic
Environment: The End of a 60-Year Search?

Stinear T, Johnson PDR

PLoS Negl Trop Dis 2(3): e216.

doi:10.1371/journal.pntd.0000216

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Here For Full Length



Written by Anna Sophia McKenney