Summary

The results of this incomplete investigation may be summarized as follows:

Clonorchiasis, a chronic affection, probably communicable, is classified under the immigration laws as a dangerous, contagious disease, and all aliens afflicted with the disease are mandatorily excludable.

The disease is present, and has been present in oriental natives of this country for a period of at least twenty years. It is prevalent in that section of China furnishing most of the present Chinese emigrants to the United States, and it is present in an appreciable percentage of those Chinese who apply for admission to the United States.

No reports have been made of the infestation of man or the lower animals who have resided continuously in the United States, nor has infestation been found during this survey in California of 407 people, 38 dogs and 8 cats, and 1468 hogs from a district in which the disease is known to be present in immigrant Asiatics.

The specific snails and fish prevalent in the waters of districts in which the disease is endemic do not inhabit the waters of the Pacific Slope, but representatives of the same families are present. Attempts to develop the larva of the fluke in these animals have thus far been negative.