TY - JOUR
T1 - Epidemiological and genetic analyses of a diffuse outbreak of hepatitis A in Japan, 2010
AU - Ishii, Koji
AU - Kiyohara, Tomoko
AU - Yoshizaki, Sayaka
AU - Wakita, Takaji
AU - Shimada, Tomoe
AU - Nakamura, Naomi
AU - Nakashima, Kazutoshi
AU - Tada, Yuki
AU - Noda, Mamoru
N1 - Funding Information:
This work was supported by Grants-in-Aid from the Ministry of Health, Labor and Welfare .
PY - 2012/3
Y1 - 2012/3
N2 - Background: Hepatitis A virus (HAV) is still one of the most common causative agents of acute hepatitis in Japan. Although a relatively small number of annual acute hepatitis A cases (approximately 100-150, 0.78-1.17 per million) were recently reported, a larger number of cases (346, 2.71 per million) were reported in 2010. Objectives: To investigate the causes of the 2010 HAV resurgence in Japan by using molecular epidemiological and genetic analyses. Study design: HAV specimens were obtained from 61 cases from 22 different prefectures. These viral specimens were genotyped by PCR amplification and sequencing of the VP1/2A region of HAV genome. Results: Phylogenetic analysis revealed that 61 HAV strains could be divided into three genotypes: IA (44 cases), IB (1 case) and IIIA (16 cases). The IA genotype consisted of two genomic sub-lineages. The sequences of one of the two IA sub-lineages (corresponding to 31 cases) were very similar, 26 of these 31 isolates had 100% identity. The other IA sub-lineage corresponded to strains endemic to Japan. The sequences of Japanese IIIA strains were similar to those of strains that caused a large epidemic in the Republic of Korea from 2007 to 2009. Conclusions: The resurgence of HAV in 2010 can be attributed to importation of two newly emerged HAV genotypes.
AB - Background: Hepatitis A virus (HAV) is still one of the most common causative agents of acute hepatitis in Japan. Although a relatively small number of annual acute hepatitis A cases (approximately 100-150, 0.78-1.17 per million) were recently reported, a larger number of cases (346, 2.71 per million) were reported in 2010. Objectives: To investigate the causes of the 2010 HAV resurgence in Japan by using molecular epidemiological and genetic analyses. Study design: HAV specimens were obtained from 61 cases from 22 different prefectures. These viral specimens were genotyped by PCR amplification and sequencing of the VP1/2A region of HAV genome. Results: Phylogenetic analysis revealed that 61 HAV strains could be divided into three genotypes: IA (44 cases), IB (1 case) and IIIA (16 cases). The IA genotype consisted of two genomic sub-lineages. The sequences of one of the two IA sub-lineages (corresponding to 31 cases) were very similar, 26 of these 31 isolates had 100% identity. The other IA sub-lineage corresponded to strains endemic to Japan. The sequences of Japanese IIIA strains were similar to those of strains that caused a large epidemic in the Republic of Korea from 2007 to 2009. Conclusions: The resurgence of HAV in 2010 can be attributed to importation of two newly emerged HAV genotypes.
KW - Diffuse outbreak
KW - Genotype
KW - Hepatitis A virus
KW - Phylogenetic analysis
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U2 - 10.1016/j.jcv.2011.11.008
DO - 10.1016/j.jcv.2011.11.008
M3 - Article
C2 - 22196871
AN - SCOPUS:84856973522
VL - 53
SP - 219
EP - 224
JO - Journal of Clinical Virology
JF - Journal of Clinical Virology
SN - 1386-6532
IS - 3
ER -