Later, a filterable organism was found in the sputum of cases and was initially termed Eaton Agent. Epidemiology of Mycoplasma pneumoniae infection Infection with Mycoplasma pneumoniae occurs worldwide. Epidemics occur more often in late summer and in autumn but endemic disease is not seasonal though incidence can vary widely from year to year. Infection tends to be asymptomatic or very mild in children under 5 and the disease is most commonly clinically recognised in school-age children and in young adults. Overall Mycoplasma pneumoniae pneumonia tends to cluster in families and other close groups.
Recurrent attacks are rare.
The disease is not particularly transmissible but it may be worthwhile testing close contacts of index cases for the disease to enable early treatment. Man is the only reservoir of Mycoplasma pneumoniae and transmission is presumably by droplet spray or by direct contact with an infected person. Clinical Presentation of Mycoplasma pneumoniae pneumonia This presents as a 'flu-like illness with unproductive cough and extensive CXR shadowing out of line with the clinical impression. The pneumonia can progress from one lobe to another. The illness lasts from a few days up to a month or so and the patient may remain 'washed-out' for a long while after resolution of specific symptoms.