The evolutionary patterns of hepatitis C virus subtype 2a and 6a isolates linked to an outbreak in China in 2012.
An HCV outbreak occurred in 2012 in China, affecting hundreds of patients. We characterized HCV subtype 2a and 6a sequences from 60 and 102 patients, respectively, and co-analyzed them with 82 local controls and 103 calibrating references. The close grouping of the patients׳ sequences contrasted sharply with the diversity of local controls. Scaled by the calibrating references, the emergence of patients׳ isolates was estimated at 2-5 years before sampling. In contrast, the controls intermingled with the calibrating references that were much older. For both subtypes, the major and minor clusters could be defined, with the closeness to indicate linked transmission.


CONCLUSIONS
HCV sequences from the study patients grouped into three subtype 2a and two subtype 6a clusters, in addition to three 6a solitary branches, representing descendants of eight earlier strains that were distinct and otherwise sporadic. Due to iatrogenic transmission through reusing needles, five strains were highly selected and preferentially spread.
Laboratory for Hepatology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China; The Center for Viral Oncology, Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS, United States of America. Electronic address: llu@kumc.edu.
Ling
L
Lu
Department of Liver Transplantation, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
Yuling
Y
An
Laboratory for Hepatology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
Ji
J
Zou
Laboratory for Hepatology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
Lin
L
Gu
Laboratory for Hepatology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
Zhixin
Z
Zhao
Laboratory for Hepatology, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
Xiaohong
X
Zhang
The Center for Viral Oncology, Department of Pathology and Laboratory Medicine, University of Kansas Medical Center, Kansas City, KS, United States of America.
Chunhua
C
Li
Department of Internal Medicine, National Defense Medical College, Tokorozawa, Saitama, Japan.
Chie
C
Kurihara
Department of Internal Medicine, National Defense Medical College, Tokorozawa, Saitama, Japan.
Ryota
R
Hokari
Department of Gastroenterology and Hepatology, Musashino Red Cross Hospital, Musashino, Tokyo, Japan.
Jun
J
Itakura
Department of Gastroenterology and Hepatology, Musashino Red Cross Hospital, Musashino, Tokyo, Japan.
Masayuki
M
Kurosaki
Department of Gastroenterology and Hepatology, Musashino Red Cross Hospital, Musashino, Tokyo, Japan.
Namiki
N
Izumi
Guangzhou Blood Center, Guangzhou, Guangdong, China.
Yongshui
Y
Fu
Department of Internal Medicine, Fujita Health University, Nanakuri Sanatorium, Tsu, Mie, Japan.
Tatsunori
T
Nakano
Department of Virology II, National Institute of Infectious Diseases, Shinjyuku, Tokyo, Japan.
Takanobu
T
Kato
Divisions of Gastroenterology and Hepatology and of Clinical pathology, University, Hospitals, Geneva, Switzerland.
Francesco
F
Negro
Department of Liver Transplantation, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China. Electronic address: chgh1955@263.net.
Guihua
G
Chen
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D004196:Disease Outbreaks; D019143:Evolution, Molecular; D005260:Female; D005814:Genes, Viral; D005838:Genotype; D016174:Hepacivirus / Q000145:classification / Q000235:genetics*; D006526:Hepatitis C / Q000453:epidemiology* / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D055815:Young Adult
Evolution; Genetic sequence; HCV; Outbreak