Melioidosis

Abstract

Burkholderia pseudomallei is a Gram-negative environmental bacterium and the aetiological agent of melioidosis, a life-threatening infection that is estimated to account for ∼89,000 deaths per year worldwide. Diabetes mellitus is a major risk factor for melioidosis, and the global diabetes pandemic could increase the number of fatalities caused by melioidosis. Melioidosis is endemic across tropical areas, especially in southeast Asia and northern Australia. Disease manifestations can range from acute septicaemia to chronic infection, as the facultative intracellular lifestyle and virulence factors of B. pseudomallei promote survival and persistence of the pathogen within a broad range of cells, and the bacteria can manipulate the host's immune responses and signalling pathways to escape surveillance. The majority of patients present with sepsis, but specific clinical presentations and their severity vary depending on the route of bacterial entry (skin penetration, inhalation or ingestion), host immune function and bacterial strain and load. Diagnosis is based on clinical and epidemiological features as well as bacterial culture. Treatment requires long-term intravenous and oral antibiotic courses. Delays in treatment due to difficulties in clinical recognition and laboratory diagnosis often lead to poor outcomes and mortality can exceed 40% in some regions. Research into B. pseudomallei is increasing, owing to the biothreat potential of this pathogen and increasing awareness of the disease and its burden; however, better diagnostic tests are needed to improve early confirmation of diagnosis, which would enable better therapeutic efficacy and survival.

Evaluating the role of Burkholderia pseudomallei K96243 toxins BPSS0390, BPSS0395, and BPSS1584 in persistent infection

“…B . pseudomallei is intrinsically resistant to most antibiotics, but a handful of antibiotics are effective for which emergence of newly resistant strains is rare (Sarovich et al, ; Schweizer, ; Wiersinga et al, ; Wuthiekanun et al, ). Still, therapeutic eradication of B .…”

Dose‐dependant acute or subacute disease caused byBurkholderia pseudomalleistrain NCTC 13392 in a BALB/c aerosol model of infection

“…Afterwards clinical scores began to increase to a mean of 3·2 by day 30 pc, weight loss (4%) was also seen. This pattern of symptoms mimicks human subacute/chronic infection; in humans, chronic melioidosis is characterized as a symptomatic infection that lasts >2 months; the nonspecific signs and symptoms, during the incubation period, can often hinder the diagnosis and treatment of this disease (Wiersinga et al ). In this study, on day 10 pc, hepatic abscesses were present and hepatic degeneration and inflammation was observed, which is consistent with subacute/chronic infection.…”

Novel multi-component vaccine approaches for Burkholderia pseudomallei

“…Historically, melioidosis was considered to be geographically restricted to countries in southeast Asia and northern Australia, because these regions have reported the highest incidence and prevalence of the disease, where annual incidence is up to 50 cases per 100 000 people [1,2]; however, the incidence of melioidosis increases in diabetic patients and, for example, in northern Australia it is estimated to be 260 cases per 100 000 [13]. The appearance of sporadic melioidosis cases and further investigation to identify other endemic areas worldwide has now expanded the global map of the disease to cover more countries within tropical areas [14], including the western hemisphere (Africa and America) [15] and the majority of the Asian continent ( Fig.…”

“…Further, the study also confirmed that B. pseudomallei isolates from African origin were transmitted to Central and South America between 1650 and 1850, which correspond to the period representing the slave trade. However, major roadblocks exist that prevent the effective determination of the burden of melioidosis, and those include diversity in the clinical manifestations, lack of basic microbiological facilities in several endemic areas, the lack of conventional bacterial identification methods and awareness and knowledge among health-care professionals and poor disease surveillance systems [2,16]. Recent efforts to educate health professionals in countries where melioidosis has been reported [18] is expected to result in a steady increase in the awareness and better diagnosis and identification of the pathogen.…”

“…The incubation period for melioidosis typically ranges from 1 to 21 days, with a median of 9 days; however, latent infections can occur, with disease manifesting decades after exposure [1][2][3]. pseudomallei is a facultative, intracellular Gram-negative bacillus and the causative agent of melioidosis.…”