Low risk of acquiring melioidosis from the environment in the continental United States

Abstract

Melioidosis is an underreported human disease of tropical and sub-tropical regions caused by the saprophyte Burkholderia pseudomallei. Although most global melioidosis cases are reported from tropical regions in Southeast Asia and northern Australia, there are multiple occurrences from sub-tropical regions, including the United States (U.S.). Most melioidosis cases reported from the continental U.S. are the result of acquiring the disease during travel to endemic regions or from contaminated imported materials. Only two human melioidosis cases from the continental U.S. have likely acquired B. pseudomallei directly from local environments and these cases lived only ~7 km from each other in rural Texas. In this study, we assessed the risk of acquiring melioidosis from the environment within the continental U.S. by surveying for B. pseudomallei in the environment in Texas where these two human melioidosis cases likely acquired their infections. We sampled the environment near the homes of the two cases and at additional sampling locations in surrounding counties in Texas that were selected based on ecological niche modeling. B. pseudomallei was not detected at the residences of these two cases or in the surrounding region. These negative data are important to demonstrate that B. pseudomallei is rare in the environment in the U.S. even at locations where locally acquired human cases likely have occurred, documenting the low risk of acquiring B. pseudomallei infection from the environment in the continental U.S.

BpOmpW antigen administered with CAF01 adjuvant stimulates comparable T cell responses to Sigma adjuvant system

“…Moreover, it is likely that melioidosis is severely underreported in the 45 countries in which it is endemic and is likely be endemic in a further 34 countries [3] . Indeed, a recent CDC Health Advisory (July 2022) has indicated that melioidosis is also endemic in areas of the Mississippi Gulf Coast and persists in the environment in Texas [4] . It is the most common cause of community-acquired bacteraemia and the third most common cause of death from infectious disease in Thailand [5] .…”

Burkholderia thailandensis Isolated from the Environment, United States

“…Occurrence of B. thailandensis in the environment in the Western Hemisphere remains poorly understood. We used a systematic approach to detect and isolate B. thailandensis from soil and water samples collected in Texas in November 2019 and November 2020 ( 9 ) and Puerto Rico during December 2018–March 2020.…”

The public health significance of finding autochthonous melioidosis cases in the continental United States

“…pseudomallei . Establishment of the disease in this environment that favors the survival of the pathogen should be seriously considered as a public health threat for the residents of the Gulf coast region [ 8 ].…”

“…However, in recent years, the presence of B. pseudomallei has been demonstrated in the African and American continents and in the Caribbean islands as well as the rest of Asia [3][4][5][6]. The continental United States had never confirmed an endemic case of the disease and it was presumed that all the melioidosis patients from the continental US acquired the disease while traveling to endemic areas around the globe [7,8]. In fact, melioidosis was considered a traveler's disease because incidence in the continental US was associated with international acquisition [9].…”

“…Emerging infectious disease: Melioidosis is considered an emerging infectious disease in regions outside the well-established endemic areas, but still not considered a neglected tropical disease [13], so detection in the environment of the continental US suggests a potential expansion in the geographic range of the B. pseudomallei. Establishment of the disease in this environment that favors the survival of the pathogen should be seriously considered as a public health threat for the residents of the Gulf coast region [8].…”