Clinical epidemiological survey of Legionella pneumophila infections in Italy.

A clinical epidemiological survey of Legionella pneumophila infections occurring in Italy between 1 December 1985 and 31 May 1986 was carried out to evaluate the incidence of sporadic, epidemic and nosocomial L. pneumophila pneumonia. A total of 355 cases of pneumonia were studied of which 11.5% were due to Gram positive bacteria, 11% were due to Gram negative bacteria, 7.9% were due to Mycoplasma pneumoniae, 4.5% were due to L. pneumophila and 8.5% were due to sundry aetiological agents. The remainder (45.6%) could not be diagnosed accurately. In addition, the anti L. pneumophila antibody titres were assessed. The results are discussed in terms of the occurrence of the disease in Italy and regarding the importance of considering the possibility of legionellosic aetiology when diagnosing pneumonia.