Table 1.
Liver viral load, liver histologic score, liver immunohistochemical staining results, and alanine aminotransferase (ALT) values for Egyptian rousette bats (Rousettus aegyptiacus) experimentally infected with Marburg virus in a serial euthanasia study.
| Case Number | Group | DPI | Viral Load (TCID50/g Equivalents) a | HE Score b | IHC c | ALT (U/L) |
|---|---|---|---|---|---|---|
| 1 | A | 3 | ++ | ++ | + | 166 |
| 2 | B | 3 | ++ | - | - | 138 |
| 3 | C | 3 | ++++ | + | + | 74 |
| 4 | A | 5 | +++ | + | - | 110 |
| 5 | B | 5 | ++++ | ++ | + | 117 |
| 6 | C | 5 | +++++ | - | + | 66 |
| 7 | A | 6 | ++ | ++ | - | 127 |
| 8 | B | 6 | ++++ | ++ | - | 131 |
| 9 | C | 6 | +++++ | ++++ | + | 74 |
| 10 | A | 7 | +++ | ++++ | + | 104 |
| 11 | B | 7 | ++++ | ++++ | + | 125 |
| 12 | C | 7 | ++++ | +++ | - | 124 |
| 13 | A | 8 | +++++ | ++++ | + | 108 |
| 14 | B | 8 | ++ | ++ | - | 122 |
| 15 | C | 8 | ++++ | +++ | - | 62 |
| 16 | A | 9 | +++ | ++ | - | 123 |
| 17 | B | 9 | + | - | - | 76 |
| 18 | C | 9 | ++ | + | - | 82 |
| 19 | A | 10 | + | - | - | 97 |
| 20 | B | 10 | ++ | ++ | - | 80 |
| 21 | C | 10 | - | - | - | 73 |
| 22 | A | 12 | + | + | - | 87 |
| 23 | B | 12 | ++ | - | - | 68 |
| 24 | C | 12 | - | - | - | 91 |
| 25 | A | 28 | - | + | - | 59 |
| 26 | B | 28 | - | - | - | 40 |
| 27 | C | 28 | - | - | - | 51 |
| 28 | A | Control | - | - | - | 52 |
| 29 | B | Control | - | - | - | 61 |
| 30 | C | Control | - | - | - | 26 |
Abbreviations: TCID50, 50% tissue culture infective dose; DPI, days post-infection; HE, hematoxylin and eosin; IHC, immunohistochemistry; ALT, alanine aminotransferase. a Viral loads are expressed as 50% tissue culture infective dose (TCID50) equivalents per gram, derived from standard curves of the diluted stock viruses assayed using the identical Q-RT-PCR protocols as that for tissues: + < 100 TCID50 eq.; ++ 100–999 TCID50 eq.; +++ 1000–9999 TCID50 eq.; ++++ 10,000–99,999 TCID50 eq.; +++++ 100,000 to 1,000,000 TCID50 eq. b Liver score based on average number and character of inflammatory foci per 100 high-powered fields: - = average of <1 focus of mononuclear inflammatory infiltrate per 100 high-powered fields (HPFs; 400x magnification); + = 1–2.9 foci of inflammatory infiltrate per 100 HPFs, with at least one focus containing hepatocellular degeneration and necrosis; ++ = 3–5.9 inflammatory foci per 100 HPFs, with multiple foci containing hepatocellular degeneration and necrosis; +++ = 6–10 inflammatory foci per 100 HPFs, with frequent hepatocellular degeneration and necrosis; and, ++++ = >10 inflammatory foci per 100 HPFs, with frequent degeneration and necrosis. c IHC staining was present in in hepatocytes and/ or macrophages, and was graded as - = no antigen detected; or, + = antigen detected.