Chronic hepatitis C in Sweden: genotype distribution over time in different epidemiological settings.
Hepatitis C virus (HCV) strains are divided into 6 genotypes and several subtypes. Recent studies reported a change in the relative frequency of genotypes within certain regions. We studied the HCV genotype in 312 Swedish patients with chronic hepatitis C, using a core region primer-specific PCR, and grouped the patients according to parenteral risk factors. The date of infection could be estimated in 127 cases. Genotypes 1a (35%) and 3 (31%) were the most common genotypes, followed by genotype 2 (17%), while only 6% had genotype 1b. Genotype 3 was relatively more frequent among subjects infected sexually or by intravenous drug use. The genotype distribution was different from that in studies from other parts of the world, with a lower frequency of genotype 1 (especially 1b) and a higher frequency of genotype 3. The frequency of genotype 1b has decreased and genotype 3 increased over time. The reasons for a different distribution of genotypes in Sweden, compared with other countries, might be a relatively recent introduction of HCV into the population, or a different pattern of transmission.
Westin
J
J
Department of Infectious Diseases, Sahlgrenska University Hospital, Ostra, Göteborg, Sweden.
Lindh
M
M
Lagging
L M
LM
Norkrans
G
G
Wejstål
R
R
D000328:Adult; D017677:Age Distribution; D000368:Aged; D005260:Female; D005838:Genotype; D019698:Hepatitis C, Chronic / Q000453:epidemiology* / Q000235:genetics*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000032:analysis*; D012307:Risk Factors; D017678:Sex Distribution; D013548:Sweden / Q000453:epidemiology; D013997:Time Factors
D012367:RNA, Viral