TABLE 3.
Clinical signs and protective efficacy in previously infected or vaccinated Gn pigs after challenge with GII.4 2006b NoVa
| Group | n | Diarrheab |
Virus shedding |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Mean % of pigs with diarrhea (no. of pigs with diarrhea/total no.)c | Mean no. of days with diarrhead (SEM) | Mean AUC from PCD 1 to PCD 7 (SEM) | Fold reduction in AUC | Rate of protection against diarrhea (%)e | Mean % of pigs shedding virus (no. of pigs shedding/total no.) | Mean no. of days with sheddingd (SEM) | Mean AUC from PCD 1 to PCD 7 (SEM) | Fold reduction in AUC | Rate of protection against shedding (%)e | ||
| NoVPO | 7 | 14 (1/7) B | 0.3 (0.3) | 6.7 (0.6) | 1.0 | 82.9 | 43 (3/7) | 2.9 (1.4) | 20,775 (57,893) | −5.6 | 48.6 |
| 100 μg P particles + MPL-chitosan (i.n.) | 9 | 44 (4/9) AB | 1.3 (0.6) | 5.4 (0.8) | −1.2 | 46.7 | 89 (8/9) | 1.8 (0.4) | 38,216 (10,568) | −3.1 | 0.0 |
| 100 μg VLPs + MPL-chitosan (i.n.) | 6 | 33 (2/6) AB | 0.7 (0.4) | 6.2 (1.0) | −1.1 | 60.0 | 100 (6/6) | 2.0 (0.4) | 96,428 (25,627) | −1.2 | 0.0 |
| Diluent 5 (oral) or MPL-chitosan (i.n.) | 6 | 83 (5/6) A | 1.8 (0.6) | 6.7 (1.0) | 1.0 | NA | 83 (5/6) | 2.0 (0.7) | 116,960 (78,189) | 1.0 | NA |
Gn pigs were challenged with the human NoV GII.4 2006b variant 092895 at the age of 33 to 34 days. Rectal swabs were collected daily after challenge to determine the occurrence of diarrhea and virus shedding by conventional and real-time RT-PCR. Virus shedding was also detected in intestinal contents.
Fecal scoring system: 0, solid; 1, pasty; 2, semiliquid; 3, liquid. Pigs with scores of 2 or higher were considered diarrheic.
Values in the same column followed by different letters differ significantly (P, <0.05 by Fisher's exact test); there is no significant difference between values followed by the same letter.
From PCD 0 to PCD 7.
Calculated as [1 − (percentage of immunized pigs in each group with diarrhea or shedding/percentage of control pigs with diarrhea or shedding)] × 100. NA, not applicable.