Reply #2: There's a difference between colonization and infection.

[NYC]

Some info:

http://www.innovations-report.de/html/berichte/biowissenschaften_chemie/bericht-24693.html

Acinetobacter baumannii, the hospital opportunist

Acinetobacter baumannii is an opportunistic pathogen operating in hospitals creating serious infections such as pneumonia. It principally affects patients who have weakened health and this is why we call it opportunistic. Moreover, the mortality rate from these infections are usually high given, on the one hand, the weakness of the patient and, on the other, A. baumannii is resistant to many antibiotics. Furthermore, once a specific course of treatment is prescribed for A. Baumannii, the pathogen has a great capacity for acquiring resistance to these antibiotics...


http://www.emedicine.com/med/topic3456.htm

...Although Acinetobacter primarily is a colonizer in the hospital environment, occasionally it causes infection. Mortality and morbidity resulting from A baumannii infection relate to the underlying cardiopulmonary immune status of the host rather than the inherent virulence of the organism.