Of 49 (19%) of 258 HBoV NPA PCR-positive children, 35 (71%) had a serodiagnosis, 33 of whom were also viremic ( Table 1 ). Of 28 patients with a high load of HBoV DNA in NPAs, 27 (96%) had an HBoV serodiagnosis, compared with only 8 (38%) of 21 with a low DNA load. Conversely, among 209 children without HBoV DNA in NPAs, 13 (6%) had a serodiagnosis, of whom 12 were also viremic.