A genus of non-motile, aerobic and facultatively anaerobic Gram-negative rod-shaped bacteria.

Klebsiella belongs to the Enterobacterales Enterobacteriaceae family. It is a common cause of both community-acquired and hospital-acquired infections, including pneumonia and respiratory tract infections.

Klebsiella is one of the ‘ESKAPE’ pathogens that make up the most common antibiotic-resistant infections. Multidrug-resistant and extensively drug-resistant Klebsiella are among the most challenging infections to treat. Carbapenem-resistant Enterobacteriaceae such as Klebsiella are categorized by WHO as a ‘priority 1 (critical)’ pathogen for R&D of new antibiotics.