Detection of Mimivirus in Bronchoalveolar Lavage of Ventilated and Nonventilated Patients

Background/Aims: We investigated the prevalence of Mimivirus in bronchoalveolar lavage (BAL) specimens from ventilated versus nonventilated patients. Methods: The occurrence of Mimivirus DNA was evaluated by two previously developed real-time PCR assays in 69 BAL specimens: 30 from patients on mechanical ventilation for at least 48 h and 39 from nonventilated patients from different clinical settings, including lung transplant recipients. Results: None of the BAL specimens from ventilated and nonventilated patients resulted positive for Mimivirus. Conclusion: This study, similarly to other studies that used molecular assays to detect Mimivirus, found no occurrence of the virus in the lower respiratory tract, thus being in contrast to serological investigations which reported a significant association between Mimivirus and the development of pneumonia. Gene polymorphism could explain these results or, alternatively, it could be hypothesized that Mimivirus does not represent a common cause of lower respiratory tract infection in either ventilated or nonventilated patients. Further studies on a larger population of patients from a different clinical setting evaluating both serology and DNA detection in lower respiratory tract specimens, including BAL and possibly tissue samples, could allow a better definition of the epidemiological and pathological role of Mimivirus in the development of pneumonia. Copyright (C) 2011 S. Karger AG, Basel