Egg laying capacity of Haplorchis taichui (Digenea: Heterophyidae) in humans

Abstract

Quantitative fecal egg counts represented as the number of eggs per gram of feces (EPG) are generally a reliable parameter to estimate the worm burden of intestinal and hepatic parasitoses. Although Haplorchis taichui (Digenea: Heterophyidae) is one of the most common minute human intestinal flukes, little is known about the relationship between EPG and the actual worm burden in patients or the severity of the disease. In the present study, fecal samples were collected from 25 villagers in northern Thailand before and after praziquantel treatment. The EPG values of each participant were determined by the modified cellophane thick smear method, and adult worms were collected from the whole stool after the treatment. Eggs per day per worm (EPDPW) of H. taichui were estimated 82 from egg counts and expelled worms. The EPG was not well correlated with the worm burden, and a reverse correlation was observed between the EPDPW and the worm burden.

Keywords: Haplorchis taichui; egg laying capacity; eggs per day per worm (EPDPW); eggs per gram of feces (EPG).

Fig. 1

Comparison of the eggs per gram of feces (EPG) obtained by the modified cellophane thick smear and modified formalin detergent methods.

Fig. 2

Marginal plots of EPG by modified cellophane thick smear and individual worm burden. Numbers of samples in each group are shown as flat columns and bars outside of the graph.

Fig. 3

Correlation of the worm number and eggs per day per worm (EPDPW).