Table 3:
Quantitative viral shedding for poliovirus type 2 after mOPV2 challenge
| mIPV2HD group | IPV group | p value | |
|---|---|---|---|
| 19 weeks (1 week after challenge) | |||
|
| |||
| n/N | 88/108 | 83/106 | .. |
| % (95% CI) | 81·5% (72·9–88·3) | 78·3% (69·2–85·7) | 0·6109* |
| Median (log) CCID50 (IQR) | 4·86 (2·84–6·20) | 4·45 (2·75–6·22) | 0·4740* |
|
| |||
| 20 weeks (2 weeks after challenge) | |||
|
| |||
| n/N | 67/108 | 64/105 | .. |
| % (95% CI) | 62·0% (52·2–71·2) | 60·9% (50·9–70·3) | 0·8888* |
| Median (log) CCID50 (IQR) | 2·83 (2·75–4·83) | 3·06 (2·75–4·72) | 0·8173* |
|
| |||
| 21 weeks (3 weeks after challenge) | |||
|
| |||
| n/N | 46/101 | 46/100 | .. |
| % (95% CI) | 45·5% (35.6–55.8) | 46·0% (36·0–56·3) | 1·0000* |
| Median (log) CCID50 (IQR) | 2·75 (2·75–3·47) | 2·75 (2·75–4·47) | 0·5365* |
|
| |||
| Infants shedding virus at any timepoint | |||
|
| |||
| n/N | 80/95 | 76/91 | .. |
| % (95% CI) | 84·2% (75·3–90·9) | 83·5% (74·3–90·5) | 1·0000 |
|
| |||
| Shedding indext † | |||
|
| |||
| Median (log) CCID50 (IQR) | 3·95 (3·18–4·85) | 4·07 (3·21–4·84) | 0·6429 |
The proportions of infants shedding virus were compared between groups using Fisher’s exact test Viral titres were compared between groups using the Mann-Whitney-Wilcoxon test. mOPV2=monovalent oral poliovirus vaccine, type 2. mIPV2HD=monovalent inactivated poliovirus vaccine, type 2, high dose. IPV=trivalent inactivated poliovirus vaccine. n=number of infants shedding virus. N=total number of infants at each timepoint. CCID50=50% cell culture infective dose.
*
Exploratory analysis.
†
Computed as the average of log10-transformed values of viral titres measured in stool collected on 7, 14, and 21 days after mOPV2 challenge.