High prevalence of mixed genotype infections in hepatitis B virus infected intravenous drug users.
The clinical relevance of hepatitis B virus (HBV) genotypes has been documented; however, the prevalence of mixed HBV genotype infections in at-risk groups remains controversial. The HBV genotypes were determined in 325 HBV-infected intravenous drug users (IVDU) who were at a greater risk of multiple exposures to different HBV genotypes by using a newly developed line probe assay. The distribution of HBV genotype was as follows: genotype A alone in 2 (0.6%); genotype B alone in 256 (78.8%); genotype C alone in 10 (3.1%); mixed genotype A and B in 18 (5.5%); genotype B and C in 30 (9.2%); genotype B and D in 1 (0.3%); genotype A and C in 1 (0.3%); and mixed infections of genotype A, B, and C in 3 (0.9%). Clonal analysis confirmed further the existence of mixed genotype infection and recombination between different genotypes. Compared with our previous data, the line probe assay seemed more sensitive than polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) assay in identifying HBV genotype (98.8% vs. 65.0%) and detecting mixed genotype infections (16.3% vs. 0%). In conclusion, the prevalence of mixed HBV infections is substantially higher in IVDU in endemic areas, and the line probe assay is a useful method for rapid genotyping of HBV, with particular reference to the detection of mixed genotype infections.
School of Medicine, Fu Jen Catholic University, Taipei, Taiwan.
Bing-Fang
BF
Chen
Pei-Jer
PJ
Chen
Guey-Mei
GM
Jow
Erwin
E
Sablon
Chun-Jen
CJ
Liu
Ding-Shinn
DS
Chen
Jia-Horng
JH
Kao
D000328:Adult; D000368:Aged; D004279:DNA, Viral / Q000032:analysis / Q000235:genetics; D005838:Genotype; D006515:Hepatitis B virus / Q000145:classification / Q000235:genetics*; D006526:Hepatitis C / Q000453:epidemiology* / Q000209:etiology / Q000821:virology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D015995:Prevalence; D017422:Sequence Analysis, DNA; D015819:Substance Abuse, Intravenous / Q000150:complications*
D004279:DNA, Viral