To evaluate changes in various biological parameters associated with influenza disease with the aim of describing a clinical profile and correlates of protection between three distinct influenza viruses. High mortality (approxInfluenza Disease Profile in FerretsFigure 4. A comparison of clinical chemistry parameters of influenza-infected ferrets. Blood was collected into SST tubes and clinical chemistry analysis was conducted on the Advia 1200 (Siemens). A comparison of the following clinical chemistry parameters was performed on ferrets infected with HPAI, seasonal, or swine influenza virus: (A) alanine aminotransferase (ALT), (B) albumin, (C) albumin/globulin ratio, (D) BMS-5 chemical information alkaline phsophatase, (E) aspartate aminotransferase (AST), (F) blood urea nitrogen (BUN), (G) BUN/creatinine ratio, (H) calcium, (I) chloride, (J) creatinine, (K) gamma glutamyl transferase (GGT), (L) globulin, (M) glucose, (N) phosphorus, (O) potassium, (P) sodium, (Q) SDH, and (R) total protein. A represents a significant difference when comparing HPAI and seasonal influenza; B represents a significant difference when comparing HPAI and swine influenza; and C represents a significant difference when comparing swine influenza and seasonal influenza. Geometric means and 95 confidence intervals (error bars) were plotted. doi:10.1371/journal.pone.0058337.gimately 93 ) was associated with ferrets infected with HPAI H5N1 A/Vn/1203/04. Other studies performed in our laboratory have demonstrated various mortality rates associated with other HPAI viral strains, but the 
highest mortality rates have been associated with H5N1 A/Vn/1203/04 (data not shown). We did not observe mortality in ferrets challenged with various seasonal or swine influenza viruses. The difference in virulence may be associated with various viral or host system factors. For instance, different BIBS39 site levels of viremia and the amount of viral replication within the specific host animal tissues may be a factor. A/Vn/ 1203/04 has been shown to have a lower infection 8 hours postinfection when compared to other influenza virus strains [11].However, H5N1 A/Vn/1203/04 replicated to titers similar to 
those of the other influenza virus strains 24 hours post-infection and induced higher levels of cell necrosis when compared to other influenza viruses [11]. This published report also demonstrates a unique ability to recover H5N1 A/Vn/1203/04 from both the apical and basolateral surfaces of cells, which may be indicative of a virulence factor that is associated with this virus [11]. Elevated mortality rates have also been correlated with elevated viral replication and viral load, resulting in extreme cytokine production [12]. Moreover, H5N1 A/Vn/1203/04 has been shown to induce elevated levels of proinflammatory cytokines when compared to other influenza viruses [11]. Additionally, theInfluenza Disease Profile in FerretsFigure 5. A comparison of hematology parameters of influenza-infected ferrets. Blood was collected into EDTA tubes and hematology analysis was conducted on the Advia 120 (Siemens). A comparison of the following hematology parameters was performed on ferrets infected with HPAI, seasonal, or swine influenza virus: (A) number of basophils, (B) number of eosinophils, (C) number of lymphocytes, (D) number of monocytes, (E) number of neutrophils, (F) percentage of basophils;, (G) percentage of eosinophils, (H) percentage of lymphocytes, (I) percentage of monocytes, (J) percentage of neutrohils, (K) CHCM (cell HG.To evaluate changes in various biological parameters associated with influenza disease with the aim of describing a clinical profile and correlates of protection between three distinct influenza viruses. High mortality (approxInfluenza Disease Profile in FerretsFigure 4. A comparison of clinical chemistry parameters of influenza-infected ferrets. Blood was collected into SST tubes and clinical chemistry analysis was conducted on the Advia 1200 (Siemens). A comparison of the following clinical chemistry parameters was performed on ferrets infected with HPAI, seasonal, or swine influenza virus: (A) alanine aminotransferase (ALT), (B) albumin, (C) albumin/globulin ratio, (D) alkaline phsophatase, (E) aspartate aminotransferase (AST), (F) blood urea nitrogen (BUN), (G) BUN/creatinine ratio, (H) calcium, (I) chloride, (J) creatinine, (K) gamma glutamyl transferase (GGT), (L) globulin, (M) glucose, (N) phosphorus, (O) potassium, (P) sodium, (Q) SDH, and (R) total protein. A represents a significant difference when comparing HPAI and seasonal influenza; B represents a significant difference when comparing HPAI and swine influenza; and C represents a significant difference when comparing swine influenza and seasonal influenza. Geometric means and 95 confidence intervals (error bars) were plotted. doi:10.1371/journal.pone.0058337.gimately 93 ) was associated with ferrets infected with HPAI H5N1 A/Vn/1203/04. Other studies performed in our laboratory have demonstrated various mortality rates associated with other HPAI viral strains, but the highest mortality rates have been associated with H5N1 A/Vn/1203/04 (data not shown). We did not observe mortality in ferrets challenged with various seasonal or swine influenza viruses. The difference in virulence may be associated with various viral or host system factors. For instance, different levels of viremia and the amount of viral replication within the specific host animal tissues may be a factor. A/Vn/ 1203/04 has been shown to have a lower infection 8 hours postinfection when compared to other influenza virus strains [11].However, H5N1 A/Vn/1203/04 replicated to titers similar to those of the other influenza virus strains 24 hours post-infection and induced higher levels of cell necrosis when compared to other influenza viruses [11]. This published report also demonstrates a unique ability to recover H5N1 A/Vn/1203/04 from both the apical and basolateral surfaces of cells, which may be indicative of a virulence factor that is associated with this virus [11]. Elevated mortality rates have also been correlated with elevated viral replication and viral load, resulting in extreme cytokine production [12]. Moreover, H5N1 A/Vn/1203/04 has been shown to induce elevated levels of proinflammatory cytokines when compared to other influenza viruses [11]. Additionally, theInfluenza Disease Profile in FerretsFigure 5. A comparison of hematology parameters of influenza-infected ferrets. Blood was collected into EDTA tubes and hematology analysis was conducted on the Advia 120 (Siemens). A comparison of the following hematology parameters was performed on ferrets infected with HPAI, seasonal, or swine influenza virus: (A) number of basophils, (B) number of eosinophils, (C) number of lymphocytes, (D) number of monocytes, (E) number of neutrophils, (F) percentage of basophils;, (G) percentage of eosinophils, (H) percentage of lymphocytes, (I) percentage of monocytes, (J) percentage of neutrohils, (K) CHCM (cell HG.
