Moraxella catarrhalis is an aerobic, Gram-negative coccobacillus – previously also referred to as Neisseria catarrhalis or Micrococcus catarrhalis. It belongs to the Moraxellaceae family and is a human mucosal pathogen.
In children, the pathogen can trigger otitis media. In adults, particularly in patients suffering from chronic obstructive pulmonary disease (COPD), Moraxella catarrhalis can cause infections of the lower respiratory tract. Further symptoms include sinusitis, bacteraemia, pneumonia (in elderly patients) and nosocomial respiratory tract infection.
Transmission probably occurs via droplets or particles in the air as well as via direct or indirect contact with contaminated persons or objects.