Epstein-Barr virus (EBV) infection in infancy.
BACKGROUND
Epstein-Barr virus (EBV) has been shown to be the cause of infectious mononucleosis (IM) and has more complicated associations with several malignant diseases. These EBV associated diseases provide a strong incentive for the development of an EBV vaccine. Most primary EBV infection during infancy and early childhood is mild or subclinical. Little is known about its infection in infancy. The pattern of EBV serological response during infancy may be important for vaccine management.


OBJECTIVE
this study has served to clarify the epidemiology and serology of primary EBV infection during early infancy.


METHODS
longitudinal serum samples from 66 Hong Kong infants were tested for EBV antibodies by immunofluorescence. Cord blood and sequential serum samples from these infants were taken at birth and then at 4-month intervals up to 2 years of age.


RESULTS
maternal antibodies were present at different levels in all cord blood specimens and in serum samples of 8 infants at 4-month of age. Evidenced by VCA-IgG seroconversion, 60.6% (40/66) infants were infected during the first 2 years of life. One episode occurred before 8 months of age but, thereafter and for the remaining 16 months of follow-up until the infants were 2 years of age, the infection occurred at essentially a constant rate affecting about 20% of the remaining seronegative infants every 4 months.


CONCLUSIONS
the abrupt onset of the infection after a delay of 8 months is a remarkable feature of primary EBV infection during infancy, which implicates a protective role for maternal antibodies. Persisting maternal antibodies may additionally serve to contain the infection once it occurred. This may partly explain why, unlike during adolescence, primary EBV infection early in life is usually asymptomatic.
Chan
K H
KH
Department of Microbiology, Queen Mary Hospital, Hong Kong, Special Administrative Region, China. dkhchan@netvigator.com
Tam
J S
JS
Peiris
J S
JS
Seto
W H
WH
Ng
M H
MH
D000914:Antibodies, Viral / Q000097:blood; D002213:Capsid / Q000276:immunology; D020031:Epstein-Barr Virus Infections / Q000097:blood / Q000453:epidemiology*; D019309:Epstein-Barr Virus Nuclear Antigens / Q000276:immunology; D005260:Female; D005312:Fetal Blood; D004854:Herpesvirus 4, Human / Q000276:immunology*; D006723:Hong Kong / Q000453:epidemiology; D006801:Humans; D007231:Infant, Newborn; D008137:Longitudinal Studies; D008297:Male; D016036:Seroepidemiologic Studies
D000914:Antibodies, Viral; D019309:Epstein-Barr Virus Nuclear Antigens