[Detection of HEV RNA amounts and genotypes in raw milks obtained from different animals]

Hepatitis E virus (HEV) is one of the major foodborne viral pathogens transmitted through the fecal-oral route. Four genotypes of HEV are known to infect humans and it is reported that different types of HEV are active in zoonotic transitions. It is known that the HEV genotype 1 and HEV genotype 2 infections are generally acute and the HEV genotype 3 infections are chronic. Therefore, in the studies related to HEV infections, it is important to determine the genotypes to monitortreatment regimens. Although raw milk is often used in communities due to its low cost, there are limited data on the rates and the genotypes of HEV in our country and in the world. In light of this information, we aimed to investigate epidemiologically the quantity and genotypes of HEV RNA in 231 raw milk (48 cow milk, 65 goat milk, 65 sheep milk, and 53 donkey milk) samples. Viral RNAs were isolated from raw milk samples and the ORF2 region of HEV was investigated by the qRt-PCR method to determine quantitatively the presence of HEV RNA. In addition, among HEV RNA positive samples, the ORF2 region of HEV was amplified by nested PCR and the amplicons were sequenced. HEV RNA was detected in 47 (20.34%) raw milk samples, Positivity was detected in 14 (29.16%) of cow milk, 12 (18.46%) of goat milk, 8 of sheep milk (12.3) and 13 of donkey milk (24.5%). The amount of HEV RNA in cow milk found as the highest in both proportion and quantity. When the distribution of the HEV genotypes in the 47 positive samples was examined, 27 (57.44%) HEV genotype 1a, 10 (21.27%) HEV genotype 1b, 4 (8.5%) HEV genotype 4c, 2 (4.2%) HEV genotype 3a, (2.13) HEV genotype 1c, 1 (2.13%) HEV genotype 3e, 1 (2.13%) HEV genotype 3f and 1 (2.13%) HEV genotype 3g were determined. Although genotype 1a is more frequent, it has been revealed that different genotypes encountered in our country. In conclusion, it has been determined that HEV, one of the major foodborne viral agents, may be encountered in raw milk, and the genotypes that can cause infections in human are found especially in raw milk from animal sources. For the prevention of foodborne outbreaks, the presence of HEV in raw milk should not be ignored.