Article

Detection and prevalence of the "f" variant of Epstein-Barr virus in southern China.

Department of Microbiology and Radiotherapy, Queen Mary Hospital, University of Hong Kong.
Virology (impact factor: 3.35). 12/1991; 185(1):67-71. pp.67-71
Source: PubMed

ABSTRACT The "f" variant of Epstein-Barr virus (EBV) may have an association with the development and/or maintenance of nasopharyngeal carcinoma (NPC) among Southern Chinese. This variant is detected at a higher frequency among individuals with elevated IgA antibody levels against EBV capsid antigen who have no detectable NPC and in NPC patients as compared to healthy individuals or patients who are in remission for NPC for over 3 years. Conversion or replacement of the f variant by the prototype BamHI F virus usually occurs by 3 to 4 years after radiotherapy. By 5 years post-therapy the majority of people in remission for NPC no longer harbor the f variant in their oropharynx. Eradication of this f variant, however, does not appear essential for maintenance of a disease-free state since several patients harboring this variant were in remission for NPC for up to 21 years. The virus strain detected directly in the nasopharynx is not always identical to that seen in the oropharynx. Dual infection was commonly observed in throat washings of NPC patients although the biopsy from tumors harbored unique strains of EBV.

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Keywords

3 years
 
4 years
 
5 years post-therapy
 
detectable NPC
 
Dual infection
 
EBV capsid antigen
 
Epstein-Barr virus
 
f variant
 
harbor
 
healthy individuals
 
higher frequency
 
IgA antibody levels
 
NPC patients
 
patients
 
patients harboring
 
prototype BamHI F virus
 
remission
 
Southern Chinese
 
throat washings
 
tumors harbored unique strains