Combating the great mimicker: latest progress in the development of Burkholderia pseudomallei vaccines

ABSTRACT

Introduction

Burkholderia pseudomallei

is an environmental intracellular Gram-negative bacterium that causes melioidosis, a severe infectious disease affecting humans and animals. An increase in melioidosis cases worldwide and the high mortality rate of the disease makes it a public health concern. Melioidosis is known as the ‘great mimicker’ because it presents with a wide range of disease manifestations. B. pseudomallei is naturally resistant to antibiotics and delay in diagnosis leads to ineffective treatment. Furthermore, there is no approved vaccine to prevent melioidosis infection in humans. Therefore, it is a priority to license a vaccine that can be used for both high-risk endemic areas and for biodefense purposes.

Areas covered

In this review, we have focussed on recent progress in the USA for the development and advancement of lead B. pseudomallei vaccine candidate(s) ready for testing in pre-clinical trials. Those candidates include live-attenuated vaccines, glycoconjugate vaccines, outer-membrane vesicles, and gold nanoparticle vaccines.

Expert opinion

Side-by-side comparison of the leading B. pseudomallei vaccine candidates will provide important information to further advance studies into pre-clinical trials. The likelihood of any of these current vaccines becoming the selected candidate that will reduce the occurrence of melioidosis worldwide is closer than ever.

KEYWORDS:

• Burkholderia pseudomallei
• glycoconjugate vaccine
• gold nanoparticle vaccine
• live-attenuated vaccine
• melioidosis
• outer-membrane vesicle
• vaccines

Article highlights

• B. pseudomallei causes melioidosis, an infectious disease of subtropical and tropical areas of the world affecting both humans and animals.

• Melioidosis is known as the ‘great mimicker’ due to highly diverse disease manifestations, making diagnosis more difficult and delaying treatment.

• Leading B. pseudomallei vaccine candidates include OMVs, live-attenuated, glycoconjugate and nanoparticle vaccines.

• Head-to-head comparison of several of these vaccines in a standardized mouse model of melioidosis infection will provide key information about antibodies and cellular immune responses that correlate with protection ahead of pre-clinical studies.

• The safety and cost-effectiveness of vaccines against melioidosis need to be evaluated for healthy populations in endemic areas as well at-risk populations elsewhere.

Declaration of interest

No potential conflict of interest was reported by the authors.