Table 3. Serologic and quantitative PCR results of consecutive serum samples from a representative child, showing all acute HBoV markers, Finland*.

Sample no.	Age at sample collection, y	Sampling interval, d	IgG absorbance	IgG interpretation†	IgM absorbance	IgM interpretation‡	IgG avidity, %§	qPCR, copies/mL
1	0.33	120	0.061	Neg	0.015	Neg
2	0.99	235	0.010	Neg	0.014	Neg
3	1.25	96	0.029	Neg	0.025	Neg
4	1.52	96	0.032	Neg	0.023	Neg
5	1.77	90	0.032	Neg	0.021	Neg
6	2.02	89	0.017	Neg	0.022	Neg
7	2.52	180	0.019	Neg	0.028	Neg
8	2.97	165	0.014	Neg	0.028	Neg	Neg	Neg
9	3.44	167	1.536	Pos	0.730	Pos	2.8	7.67 × 104
10	3.93	178	2.883	Pos	0.023	Neg	60.8	Neg
11	4.46	190	3.412	Pos	0.035	Neg
12	4.91	163	3.111	Pos	0.022	Neg
13	5.45	193	3.754	Pos	0.033	Neg
14	5.96	185	3.228	Pos	0.020	Neg
15	7.07	398	3.183	Pos	0.030	Neg
16	7.52	163	3.102	Pos	0.026	Neg
17	8.07	198	3.450	Pos	0.027	Neg
18	8.53	165	3.149	Pos	0.016	Neg
19	9.07	195	3.252	Pos	0.024	Neg	49.2

*This child experienced an acute HBoV infection at 3 years of age (sample no. 9), evidenced by: IgG conversion, IgM, low IgG avidity and viremia (boldface). HBoV, human bocavirus; qPCR, quantitative PCR in serum; neg, negative; pos, positive; blank cells, not done.
†The cutoff absorbances for negative and positive IgG results were 0.154 (mean + 3 SD) and 0.188 (mean + 4 SD), respectively (13).
‡The cutoff absorbances for negative and positive IgM results were 0.136 (mean + 3 SD) and 0.167 (mean + 4 SD), respectively (13).
§The low- and high-avidity cutoff values: 15% and 25%, respectively (17).