Survival of Francisella tularensis Type A in brackish-water
Martha’s Vineyard (MV), Massachusetts has been the location of two outbreaks of pneumonic tularemia; landscaping activities have been associated with risk, suggesting environmental inhalation exposure. We determined whether salinity or other components of brackish-water present in a location with endemic tularemia may prolong survival of F. tularensis. In addition, we demonstrate for the first time that F. tularensis Type A appears similar to Type B with respect to environmental stability. The results of this study suggest an explanation for why MV is the site of pneumonic tularemia transmission as opposed to sites in the southcentral USA, where tularemia is more commonly reported: Bacteria may be more prone to surviving in salt-influenced soil or moisture in the island setting.
KeywordsTularemia Environmental stability Microcosm Type A Martha’s Vineyard
We thank the Vineyard Open Land Foundation for access to study sites. John Varkonda of the Massachusetts Department of Conservation and Recreation provided valuable logistical support, and many other individuals and agencies of Martha’s Vineyard facilitated our research. This contribution is a part of a dissertation submitted in partial fulfillment of the requirements for the PhD in Biomedical Sciences at Tufts University (ZLB). Our work is funded by grants from the National Institutes of Health (R21 AI 053411, RO1 AI 064218, and NO1 AI 30050).
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