Up. The duration of ICU stay and the ICU mortality rate were significantly higher in patients developing an active CMV infection than in patients from the control group (Table 4). However, there was no difference between the CMV group and the HSV group regarding these parameters. There was no correlation between the viral load and the number of ventilator-free days at D28 and D60 (data not shown).Impact of CMV and HSV on Ventilated PatientsFigure 3. Meta-analyse of the mortality associated with Herpes Simplex Virus (HSV) Diagnosis methods are detailed in table 6. doi:10.1371/journal.pone.0051340.gComplications such as bacteremia, acute renal failure or shock were significantly more frequent in the CMV group (Table 4). In contrast, there were no increases in the rate of inhibitor bacterial VAP or ARDS following virus identification in the CMV group when compared to the other two groups.DiscussionThe present study suggests that an active CMV infection in critically ill patients increases both crude and adjusted mortalities at day 60. CMV infection was also associated with less ventilator free days at day 28 and day 60, and an increased duration of ICUTable 5. Diagnosis Methods used to diagnose CMV infection.CMV Domart 1990 [39] Cook 1998 [35] Kutza 1998 [37] Heininger 2001 [4] Cook 2003 [2] Jaber 2005 [14] Limaye 2008 [13] Von Muller 2006 [47] Ziemann 2008 [24] Chiche 2009 [23] Chilet 2010 [34] Heininger 2011 [17] CoiselSample Blood, urine Lower Epigenetics respiratory tract, tracheal aspiration, blood, skin Blood Blood, lower respiratory tract Blood, tracheal aspiration Blood Blood Blood, tracheal aspiration, urine Blood Blood, lower respiratory tract Blood, tracheal aspiration Blood, tracheal aspiration Blood, lower respiratory tractDiagnosis methods Viral culture Viral culture PP65 antigenemia, PCR Viral culture, PCR Serology, viral culture PP65 antigenemia PCR Serology, PP65 antigenemia, viral culture in blood, tracheal aspiration and urine PCR Serology, PP65 antigenemia, viral culture in BAL PCR PCR Serology, BAL-PCR, PP65 antigenemiaBAL, bronchoalveolar lavage; PCR, polymerase chain reaction. doi:10.1371/journal.pone.0051340.tImpact of CMV and HSV on 23727046 Ventilated PatientsTable 6. Diagnosis Methods used to diagnose HSV infection.HSV Cook 1998 [35] Bruynseels 2003 [9] Cook 2003 [2] Ong 2004 [38] Engelmann 2007 [36] Luyt 2007 [10] Linssen 2008 [18] De Vos 2009 [8] Scheithauer 2010 [19] Smith 2010 [12] Bouza 2011 [48] CoiselSample Lower respiratory tract, tracheal aspiration, blood, skin Lower respiratory tract, throat Tracheal aspiration Lower respiratory tract, throat Lower respiratory tract, tracheal aspiration, throat Lower respiratory tract, tracheal aspiration, bronchial biopsies Lower respiratory tract Lower respiratory tract Lower respiratory tract, tracheal aspiration Tracheal aspiration Lower respiratory tract Blood, lower respiratory TractDiagnosis methods viral culture viral culture viral culture PCR PCR, viral culture, direct immunofluorescence BAL-PCR, BAL-viral culture, cytology PCR PCR PCR PCR viral culture Serology, BAL-PCRBAL, bronchoalveolar lavage; PCR, polymerase chain reaction. doi:10.1371/journal.pone.0051340.tstay compared with patients without CMV and HSV identification. Infection with a Herpesviridae family virus, namely CMV and HSV, is very common in the general population, whether they are immunosuppressed or not [33,34,35,36,37,38]. In critically ill patients, the incidence of both active CMV and HSV infection is matter of controve.Up. The duration of ICU stay and the ICU mortality rate were significantly higher in patients developing an active CMV infection than in patients from the control group (Table 4). However, there was no difference between the CMV group and the HSV group regarding these parameters. There was no correlation between the viral load and the number of ventilator-free days at D28 and D60 (data not shown).Impact of CMV and HSV on Ventilated PatientsFigure 3. Meta-analyse of the mortality associated with Herpes Simplex Virus (HSV) Diagnosis methods are detailed in table 6. doi:10.1371/journal.pone.0051340.gComplications such as bacteremia, acute renal failure or shock were significantly more frequent in the CMV group (Table 4). In contrast, there were no increases in the rate of bacterial VAP or ARDS following virus identification in the CMV group when compared to the other two groups.DiscussionThe present study suggests that an active CMV infection in critically ill patients increases both crude and adjusted mortalities at day 60. CMV infection was also associated with less ventilator free days at day 28 and day 60, and an increased duration of ICUTable 5. Diagnosis Methods used to diagnose CMV infection.CMV Domart 1990 [39] Cook 1998 [35] Kutza 1998 [37] Heininger 2001 [4] Cook 2003 [2] Jaber 2005 [14] Limaye 2008 [13] Von Muller 2006 [47] Ziemann 2008 [24] Chiche 2009 [23] Chilet 2010 [34] Heininger 2011 [17] CoiselSample Blood, urine Lower respiratory tract, tracheal aspiration, blood, skin Blood Blood, lower respiratory tract Blood, tracheal aspiration Blood Blood Blood, tracheal aspiration, urine Blood Blood, lower respiratory tract Blood, tracheal aspiration Blood, tracheal aspiration Blood, lower respiratory tractDiagnosis methods Viral culture Viral culture PP65 antigenemia, PCR Viral culture, PCR Serology, viral culture PP65 antigenemia PCR Serology, PP65 antigenemia, viral culture in blood, tracheal aspiration and urine PCR Serology, PP65 antigenemia, viral culture in BAL PCR PCR Serology, BAL-PCR, PP65 antigenemiaBAL, bronchoalveolar lavage; PCR, polymerase chain reaction. doi:10.1371/journal.pone.0051340.tImpact of CMV and HSV on 23727046 Ventilated PatientsTable 6. Diagnosis Methods used to diagnose HSV infection.HSV Cook 1998 [35] Bruynseels 2003 [9] Cook 2003 [2] Ong 2004 [38] Engelmann 2007 [36] Luyt 2007 [10] Linssen 2008 [18] De Vos 2009 [8] Scheithauer 2010 [19] Smith 2010 [12] Bouza 2011 [48] CoiselSample Lower respiratory tract, tracheal aspiration, blood, skin Lower respiratory tract, throat Tracheal aspiration Lower respiratory tract, throat Lower respiratory tract, tracheal aspiration, throat Lower respiratory tract, tracheal aspiration, bronchial biopsies Lower respiratory tract Lower respiratory tract Lower respiratory tract, tracheal aspiration Tracheal aspiration Lower respiratory tract Blood, lower respiratory TractDiagnosis methods viral culture viral culture viral culture PCR PCR, viral culture, direct immunofluorescence BAL-PCR, BAL-viral culture, cytology PCR PCR PCR PCR viral culture Serology, BAL-PCRBAL, bronchoalveolar lavage; PCR, polymerase chain reaction. doi:10.1371/journal.pone.0051340.tstay compared with patients without CMV and HSV identification. Infection with a Herpesviridae family virus, namely CMV and HSV, is very common in the general population, whether they are immunosuppressed or not [33,34,35,36,37,38]. In critically ill patients, the incidence of both active CMV and HSV infection is matter of controve.