[A natural opisthorchiasis foci in Kazakhstan].

The structure of many opisthorchiasis foci in Kazakhstan has not been finally determined. Occurrence of opisthorchis in wild animals is not indisputable evidence of the natural character of the focus. The role of humans in the circulation of causative agents is also rather important. Most of the foci in the republic are probably of a mixed or purely anthropogenic character, the purely natural ones are more rare.