Review
Copyright ©The Author(s) 2022.
World J Gastroenterol. Jul 21, 2022; 28(27): 3282-3296
Published online Jul 21, 2022. doi: 10.3748/wjg.v28.i27.3282
Table 1 Prevalence of hepatitis B surface antigen

Low prevalence area (< 2%)
Area of medium prevalence (2%-7%)
Area of high prevalence (> 8%)
Geographical areasUnited states, Canada, and Western European countriesParts of Russia, border Eurasian, and Asian-African areasAsia, sub-Saharan Africa, South, and Central America
% of the world population12%43%45%
Table 2 Classification of hepatitis B virus
Genus
Orthohepadnavirus
FamilyHepadnaviridae
SpeciesHBV
GenotypesA-J
Virion42 nm, spherical
EnvelopeYes (HBs)
GenomeCircular ds/ssDNA
Genome size3.2 kb
SensitivityAcid-sensitive
Virus antigensHBsAg, HBcAg, HBeAg, polymerase
Table 3 Prevalence of hepatitis B virus genotypes and subgenotypes
Genotype
Subgenotype
Prevalence
AA1 -A6Africa, India, Northern Europe, USA
BB1-B8Asia, USA
CC1-C14Asia, USA
DD1-D9India, Middle East, Southern Europe, USA
EF1-F4West and South Africa
FCentral and South America
GEurope, USA
HCentral and South America, California (USA)
II1-12Vietnam
JJapan