Prevalence of HEV infection in Tibetan swine. A, the positive rate of HEV RNA in feces and serum samples of Tibetan swine, China; B, the different of HEV RNA positive rate in feces and serum between the gender in two cities; C, the virus titer in feces and serum of Tibetan pigs, China. Unit for feces samples, copies/g; Unit for serum samples, copies/ml.