* need for hospitalization at the time of diagnosis * current need for supplemental oxygen or positive pressure support and/or has required supplemental oxygen or positive pressure support for \>or= 24 hours * \>10 days since symptom onset * diagnosis of chronic obstructive pulmonary disease (copd) * pregnant * positive for hepatitis c virus (hcv), hepatitis b virus (hbv) or human immunodeficiency virus * inability to electronically complete study questionnaires in english

* need for hospitalization at the time of diagnosis * current need for supplemental oxygen or positive pressure support and/or has required supplemental oxygen or positive pressure support for \>or= 24 hours * \>10 days since symptom onset * diagnosis of chronic obstructive pulmonary disease (copd) * pregnant * positive for hepatitis c virus (hcv), hepatitis b virus (hbv) or human immunodeficiency virus * inability to electronically complete study questionnaires in english

- need for hospitalization at the time of diagnosis - current need for supplemental oxygen or positive pressure support and/or has required supplemental oxygen or positive pressure support for >or= 24 hours - >10 days since symptom onset - diagnosis of chronic obstructive pulmonary disease (copd) - pregnant - positive for hepatitis c virus (hcv), hepatitis b virus (hbv) or human immunodeficiency virus - inability to electronically complete study questionnaires in english

- need for hospitalization at the time of diagnosis - current need for supplemental oxygen or positive pressure support and/or has required supplemental oxygen or positive pressure support for >or= 24 hours - >10 days since symptom onset - diagnosis of chronic obstructive pulmonary disease (copd) - pregnant - positive for hepatitis c virus (hcv), hepatitis b virus (hbv) or human immunodeficiency virus - inability to electronically complete study questionnaires in english