Explore the recorded discovery and history of Mycoplasma pneumoniae, with source links and stated limits.
PHAC describes M. pneumoniae as a spindle-shaped, pleomorphic bacterium measuring 1 to 2 micrometres long by 0.1 to 0.2 micrometres wide that lacks a cell wall, has a three-layered membrane containing sterols for structural support, and uses gliding motility instead of pili or flagella. CDC states that the bacteria cause respiratory tract infections and can damage the lining of the throat, windpipe and lungs, that the most common presentation is a chest cold while pneumonia is less common, and that it can take 1 to 4 weeks for symptoms to appear after exposure. Having no cell wall is the reason cell-wall antibiotics such as penicillins do not work against it. PHAC describes cyclic epidemics every 3 to 6 years.
LPSN records Mycoplasma pneumoniae Somerson et al. 1963, effectively published in the American Journal of Hygiene in a paper on haemolysin production as an aid in identifying and quantifying the Eaton agent, and retained on the 1980 Approved Lists of Bacterial Names. Type strain FH / ATCC 15531 / NCTC 10119. The earlier name “Eaton agent” reflects that the organism had been recognised as a transmissible cause of atypical pneumonia before it was classified.
LPSN records the combination Mycoplasmoides pneumoniae (Somerson et al. 1963) Gupta et al. 2018 as the correct name following a genome-based reclassification of the phylum, with Mycoplasma pneumoniae listed as a synonym. Clinical and public-health sources including CDC and PHAC continue to use Mycoplasma pneumoniae, which is the name this profile displays; the reassignment is recorded here rather than hidden.
These references do not identify a first person ever infected. Atypical pneumonia was described clinically and the transmissible Eaton agent was studied before the organism was named in 1963, so the naming date cannot stand in for a first case or a place of origin.
Source check: 2026-09-20. Educational content; independent scientific review remains pending.