Volume 15, Number 9—September 2009
Clinical Assessment and Improved Diagnosis of Bocavirus-induced Wheezing in Children, Finland
|PCR result||No. children||Serodiagnoses, IgM+,† no (%)
||No serodiagnoses, no. (%)
|NPA+ serum+||34||33 (97)||21||4||6||2||1||0||1||0|
|NPA+ serum–||15||2 (13)||0||0||2||0||13||10||3||0|
|NPA– serum–||194||1† (0.5)||1†||0||0||0||193||100||88||5|
|NPA– serum+||15||12 (80)||6||1||2||3||3||1||2||0|
|NPA+, high load||28||27 (96)||21||3||2||1||1||0||1||0|
|NPA+, low load||21||8 (38)||0||1||6||1||13||10||3||0|
*EIA, enzyme immunoassay; Ig, immunoglobulin; serodiagnoses (SDG), IgM positive and/or IgG conversion or increase; no serodiagnoses, IgM negative and no seroconversion/increase; SC, seroconversion; SI, serologic increase (>-fold increase in IgG); IgG+, constant level (<4-fold increase) of IgG in paired serum samples; IgG–, IgG negative in both serum samples; NPA, nasopharyngeal aspirate; Serum+, PCR positive in either or both serum samples.
†One child was IgM negative. The IgG value of the convalescent-phase serum sample barely exceeded the cutoff value and the child was considered as not having an acute human bocavirus infection.
‡One of 259 children (10) was not included in this comparison because of depletion of the convalescent-phase serum sample before the PCR (NPA and acute-phase serum samples were PCR negative; both serum samples were IgG positive and IgM negative, indicating immunity).