Twenty-three Haemophilus influenzae-murium strains were isolated from the nasopharynx of healthy CFLP white mice. Microbiological characterization of the cultures confirmed the taxonomic position of the organisms which had become problematic due to the loss of the original isolates. The type strain proposed, EO1, is available from the Hungarian National Collection of Medical Bacteria, National Institute of Public Health, Budapest as 95001.