Epidemiology of zoonotic hepatitis E: a community-based surveillance study in a rural population in China.
BACKGROUND
Hepatitis E is caused by two viral genotype groups: human types and zoonotic types. Current understanding of the epidemiology of the zoonotic hepatitis E disease is founded largely on hospital-based studies.


METHODS
The epidemiology of hepatitis E was investigated in a community-based surveillance study conducted over one year in a rural city in eastern China with a registered population of 400,162.


RESULTS
The seroprevalence of hepatitis E in the cohort was 38%. The incidence of hepatitis E was 2.8/10,000 person-years. Totally 93.5% of the infections were attributed to genotype 4 and the rest, to genotype 1. Hepatitis E accounted for 28.4% (102/359) of the acute hepatitis cases and 68.9% (102/148) of the acute viral hepatitis cases in this area of China. The disease occurred sporadically with a higher prevalence during the cold season and in men, with the male-to-female ratio of 3∶1. Additionally, the incidence of hepatitis E increased with age. Hepatitis B virus carriers have an increased risk of contracting hepatitis E than the general population (OR = 2.5, 95%CI 1.5-4.2). Pre-existing immunity to hepatitis E lowered the risk (relative risk  = 0.34, 95% CI 0.21-0.55) and reduced the severity of the disease.


CONCLUSIONS
Hepatitis E in the rural population of China is essentially that of a zoonosis due to the genotype 4 virus, the epidemiology of which is similar to that due to the other zoonotic genotype 3 virus.
Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu Province, China.
Feng-Cai
FC
Zhu
National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China.
Shou-Jie
SJ
Huang
National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China.
Ting
T
Wu
Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu Province, China.
Xue-Feng
XF
Zhang
Dongtai Center for Disease Control and Prevention, Dongtai, Jiangsu Province, China.
Zhong-Ze
ZZ
Wang
Jiangsu Provincial Center for Disease Control and Prevention, Nanjing, Jiangsu Province, China.
Xing
X
Ai
National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China.
Qiang
Q
Yan
Dongtai Center for Disease Control and Prevention, Dongtai, Jiangsu Province, China.
Chang-Lin
CL
Yang
Dongtai Center for Disease Control and Prevention, Dongtai, Jiangsu Province, China.
Jia-Ping
JP
Cai
Dongtai Center for Disease Control and Prevention, Dongtai, Jiangsu Province, China.
Han-Min
HM
Jiang
Dongtai Center for Disease Control and Prevention, Dongtai, Jiangsu Province, China.
Yi-Jun
YJ
Wang
National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China.
Mun-Hon
MH
Ng
National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China.
Jun
J
Zhang
National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Public Health, Xiamen University, Xiamen, China.
Ning-Shao
NS
Xia
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D044466:Asian People / Q000706:statistics & numerical data; D002648:Child; D002681:China / Q000453:epidemiology; D003080:Cold Temperature; D005260:Female; D005838:Genotype; D016751:Hepatitis E / Q000453:epidemiology* / Q000208:ethnology / Q000821:virology; D016752:Hepatitis E virus / Q000235:genetics / Q000276:immunology; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance / Q000379:methods*; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data*; D012621:Seasons; D016036:Seroepidemiologic Studies; D012737:Sex Factors; D015047:Zoonoses / Q000453:epidemiology* / Q000208:ethnology / Q000821:virology
D000914:Antibodies, Viral