The development of interstitial pneumonia and pneumonitis is often associated with HHV-6 infection/reactivation in patients who have undergone transplantation (Yamamoto 2005, Bommer 2009, Costa 2010, Mariotte 2011). Furthermore, the detection of HHV-6 DNA in the bronchalveolar lavage fluid has been identified as a risk factor for the development of bronchiolitis obliterans syndrome (Neurohr 2005) and organizing pneumonia (Costa 2010) in lung transplant patients. Acute respiratory failure due to HHV-6 has been successfully treated with foscarnet antiviral therapy (Mariotte 2011).