Melioidosis: An Emerging Under-diagnosed Tropical Infection

Abstract

Melioidosis is a serious infectious disease caused by the environmental Gram-negative bacterium Burkholderiapseudomallei. The organism is naturally found in soil and stagnant water, particularly in tropical regions. The disease is a major public health challenge, but it is frequently unrecognized in endemic areas such as Southeast Asia and northern Australia. Individuals with occupations that involve agricultural work pose a greater risk to infection, with exposure to contaminated environments being common. However, despite many people having contact with the pathogen, only a small proportion develop melioidosis. This evidence suggests the presence of both bacterial and individual host factors that influence the risk of infection and the severity of the disease. Recent advances in genomic research provide new opportunities to explore the interplay between bacterial variation and human genetic diversity in infectious diseases. Ongoing research investigates combined analyses of the pathogen and the host in the context of integrated genomic approaches. Projects such as BurkHostGEN obtain biological samples from infected patients but also healthy populations and analyze host DNA, gene expression, and the genetic variation of the bacterium. Researchers investigate environmental sources, such as the presence of B. pseudomallei in household water, to determine the presence and diversity of the pathogen. Integrating microbial genome-wide association studies in conjunction with host genetic data represents an emerging strategy to identify the genetic factors associated with the risk for infection, disease progression, and clinical outcomes in patients with melioidosis. In the long term, such comprehensive genomic studies can improve the overall understanding of melioidosis and further contribute to research of infectious diseases with environmental transmission. Keywords: Genomic Research; Melioidosis; Burkholderiapseudomallei; Host–pathogen interaction; Infectious disease epidemiology; Environmental transmission