Table 1.
Attachment of Human and Avian Influenza Viruses to Different Parts of the Human Upper Respiratory Tract
| n | Human
|
Avian
|
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Seasonal H3N2
|
Seasonal H1N1
|
Pandemic H1N1
|
HPAIV H5N1
|
LPAIV H5N9
|
LPAIV H7N7
|
||||||||
| Cilia | Goblet | Cilia | Goblet | Cilia | Goblet | Cilia | Goblet | Cilia | Goblet | Cilia | Goblet | ||
| Nasal septum | 2 | ++ | + | ++ | + | ++ | + | − | − | +/− | − | +/− | − |
| Concha inferior | 5 | ++ | + | ++ | + | ++ | + | − | − | − | − | +/− | − |
| Concha media | 3 | ++ | + | ++ | + | + | + | − | − | +/− | − | +/− | − |
| Nasopharynx | 5 | ++ | + | ++ | + | ++ | + | +/− | − | + | − | +/− | − |
| Paranasal sinuses | 2 | ++ | + | ++ | + | ++ | + | +/− | − | +/− | − | +/− | − |
| Larynx | 5 | ++ | + | ++ | + | +/− | + | − | − | − | − | − | − |
Scores are median scores from individual tissues. Attachment of influenza viruses to the apical site of ciliated epithelial cells (− indicates no attachment; +/−, < 10% cells positive; +, < 50% cells positive; ++, ≥ 50% cells positive) and to the cytoplasm of goblet cells (− indicates no attachment; +, intracellular attachment) was scored. All viruses attached occasionally to epithelial cells of the submucosal glands.