Klebsiella pneumoniae is a World Health Organization priority antimicrobial resistant pathogen highlighted for urgent development of novel control strategies such as vaccines. Two major vaccine use cases have been proposed; i) prevention of opportunistic healthcare-associated infections in vulnerable groups such as the elderly and immunocompromised and; ii) a maternal vaccine to protect new born babies in low resource settings where K. pneumoniae is the dominant Gram-negative cause of neonatal sepsis.
Following the global success of glycoconjugate vaccines targeting Haemophilus influenzae B and Streptococcus pneumoniae among others, there has been a swell of interest in anti-K. pneumoniae vaccines targeting the polysaccharide capsule and/or outer lipopolysaccharide (O antigen). However, until recently very little was known about capsule and O antigen diversity and epidemiology, because serological typing approaches were not broadly accessible and/or failed to accurately distinguish the full diversity of K. pneumoniae polysaccharides. This knowledge gap poses a major barrier for vaccine design because there was no way to determine which of the many diverse polysaccharides should be included to achieve high population coverage. Fortunately, genome-based typing approaches and sero-epidemiology analyses can go a long way to fill this information void.
In this presentation I will discuss progress of the genome-based capsule and O antigen typing tool, Kaptive, and its application to reveal key insights into K. pneumoniae sero-epidemiology; from Kaptive’s initial inception in 2015, to recent work informing the design of a novel maternal anti-K. pneumoniae vaccine, and the key challenges that remain.