Group Tx-vac-flu (n=18) Tx-no vac-flu (n=6) Healthy-flu (n=12) Tx-vac-no flu (n=13) Transplant within the preceding 6 months (n [%]) 2 [11%] 3 [50%] N/A 5 [38%] *FEV1 (L) {median [IQR]} 1.59 [0.99 - 2.51] 3.61† [3 - 4.61] 2.79 [2.14 - 3.39] *FEV1 < 2L (n [%] 5 [50%] 1 [20%] 2 [22%] #IgG (mg/dL) {median [IQR]} 761 [484 - 947] 580 [527 - 654] 641 [586 - 876] #IgG < 600 mg/dL (n [%]) 6 [33%] 3 [50%] 6 [50%] **ATP (ng/mL) immune function assay {median [IQR]} 212 [154 - 384] 199 [140 - 258] 425 [268 - 446] **ATP immune function assay < 200 ng/mL (n [%]) 7 [47%] 1 [50%] 1 [11%] Rejection or GVHD in the 30 days preceding diagnosis of influenza (n [%]) 1 [6%] 1 [17%] N/A Concomitant infections (n [%]) ††8 [44] 0 [0%] ##1 [8%] 13 [100%]∆ Tx-vac-flu=Transplant recipients who developed influenza despite influenza vaccination Tx-no vac-flu=Transplant recipients who developed influenza in the absence of influenza vaccination Healthy-flu=Healthy people who developed influenza Tx-vac-no flu=Transplant recipients who received influenza vaccination and did not develop influenza N/A=not applicable. FEV1=Forced expiratory volume in 1 second. IQR=interquartile range. IgG=Immunoglobulin G level. ATP=Adenosine triphosphate. GVHD=graft-versus-host disease *10 patients in the tx-vac-flu group, 5 in the tx-no vac-flu group, none in the healthy-flu group, and 9 in the tx-vac-no flu group had FEV1 measured. †P=0.014 compared to the tx-vac-flu group #17 patients in the tx-vac-flu group, 5 in the tx-no vac-flu group, none in the healthy-flu group, and 13 in the tx-vac-no flu group had IgG level measured. Normal range for IgG level=717 - 1411 mg/dL. **15 patients in the tx-vac-flu group, 2 in the tx-no vac-flu group, none in the healthy-flu group, and 9 in the tx-vac-no flu group had ATP level measured. Normal range for ATP level=225 - 525 ng/mL ††Concomitant infections in the tx-vac-flu group were cytomegalovirus viremia (CMV) (2), Epstein-Barr virus (EBV) related posttransplant lymphoproliferative disease (2), aspergillus fumigatus pneumonia (1), methicillin-susceptible staphylococcus aureus pneumonia (1), rotavirus enteritis (1), respiratory syncytial virus upper respiratory tract infection (1), urinary tract infection (UTI) with proteus vulgaris and klebsiella pneumoniae (1), skin infection with mycobacterium cheloniae-abscessus (1), pseudomonas aeruginosa pneumonia (1), and EBV viremia (1). ##1 patient in the healthy-flu group had concomitant sinusitis P=0.043 compared to the tx-vac-flu group Patients in the tx-vac-no flu group did not have influenza, but had CMV viremia (5), peritonitis (2), UTI (2), bacteremia (2), aspergillosis (1), sinusitis (1), EBV viremia (1), cryptococcosis (1), bacterial pneumonia (1), hepatic candidiasis (1), and clostridium-difficile-associated diarrhea (1). ∆P=0.0009 compared to the tx-vac-flu group P=not significant for all other comparisons to the tx-vac-flu group in this table.

Table 4: Risk factors for influenza.