Penza Oblast, located about 400 miles southeast of Moscow, saw 18 cases of the parasitic disease, Opisthorchiasis, in 2021, according to the regional department of Rospotrebnadzor.
Four of the cases were reported in children.
The natural foci of opisthorchiasis in the Penza region are the Bessonovsky, Luninsky and Shemysheysky districts.
Rospotrebnadzor says the incidence is due to an increase in the amount of home-cooked fish and fish products in the diet of residents of coastal cities and towns, an increase in the number of amateur fishermen and poachers, uncontrolled export of fish and fish products from opisthorchiasis and diphyllobothriasis foci, and the sale of fish and fish products in unauthorized markets.
The Opisthorchiidae of importance to humans are Opisthorchis felineus, Opisthorchis viverrini, and Clonorchis sinensis, each of which has a discrete, though occasionally overlapping, geographical distribution: O. felineus is endemic in Europe and Russia.
The morbidities associated with opisthorchiasis are largely hepatobiliary, specifically stemming from bile duct fibrosis and cholangitis, and are expressed in a variety of manifestations, such as obstructive jaundice, hepatomegaly, abdominal pain, and nausea.