The impact of serological features in Chinese children with primary or past Epstein-Barr virus infections.

Background: Epstein-Barr virus (EBV) is a primary cause of infectious mononucleosis (IM) throughout the world, and the positive serology rate changes over time in infected individuals. The aim of this study was to explore the serological and clinical features among Chinese children with EBV infections. A retrospective study of children suspected of having IM was conducted. Peripheral blood samples were analyzed by indirect immunofluorescence to detect any EBV-specific antibodies. Samples were classed as positive (+) or negative (-) to immunoglobulins M (IgM) or G (IgG) to the viral capsid antigen (VCA) or EBV nuclear antigen (EBNA). A standard medical history was taken, including epidemiological data and noting any clinical manifestations.

Results: Of 317 children, 37 were aged <8 months; 10 of these were VCA-IgM+, and the youngest was aged 1 month; 280 were aged >8 months. The EBV infection rate ranged from 21.4% among subjects aged 8-12 months to 84.2% in those aged >9 years. Serologically, children who tested as VCA-IgM+ together with VCA-IgG and EBNA-IgG- had longer hospital stays with more palatal petechiae and lymphadenopathy, especially among those with an atypical lymphocyte count of >10%. Children with the serological patterns [VCA-IgM-, VCA-IgG+ and EBNA-IgG-] and [VCA-IgM+ VCA-IgG+ and EBNA-IgG+] did not show specific clinical features.

Conclusions: Infants aged <8 months could be infected with EBV. About 84% of these Chinese children aged >9 years had serological evidence of EBV infection, whereas IM peaked in patients aged 2-3 years.