Table 3.
Proportion of Children Seropositive to Human Papillomavirus Type 6 L1, E2, E4, E6, and E7 Proteins at Each Follow-up Visit, and Time to Seroconversion
| HPV-6 | Follow-up Visit | Seroconversion | ||||||
|---|---|---|---|---|---|---|---|---|
| 1 mo (n = 232) | 2 mo (n = 239a) | 6 mo (n = 263) | 12 mo (n = 272) | 24 mo (n = 250) | 36 mo (n = 243) | No. | Median Time, mo (Range) | |
| L1 | 31.5 (73) | 18.8 (45) | 17.8 (47) | 25.0 (68) | 37.2 (93) | 31.3 (76) | 159 | 11.8 (0.9–38.1) |
| E2 | 3.9 (9) | 2.5 (6) | 3.4 (9) | 9.2 (25) | 12.4 (31) | 17.3 (42) | 70 | 23.7 (1.0–42.2) |
| E4 | 0.4 (1) | 0.8 (2) | 2.3 (6) | 4.8 (13) | 8.0 (20) | 5.3 (13) | 32 | 23.2 (5.2–42.2) |
| E6 | 0.0 (0) | 0.4 (1) | 1.5 (4) | 3.7 (10) | 6.0 (15) | 4.1 (10) | 19 | 23.4 (5.3–36.0) |
| E7 | 0.0 (0) | 0.0 (0) | 0.4 (1) | 0.4 (1) | 1.6 (4) | 3.3 (8) | 13 | 35.4 (5.8–37.1) |
Data are presented as proportion (%) of seropositive children. Cut-off for L1 seropositivity was median fluorescence intensity (MFI) ≥200. Cut-off for E2, E4, E6, and E7 seropositivity was MFI ≥100.
Abbreviation: HPV-6, human papillomavirus type 6.
aOnly 237 children for E2 and E4.