A survey on the prevalence of intestinal protozoan cysts was conductcd in Jeonlanam Do (Province), Korea in 1981. A total of 4,116 specimens was collected from 2,035 male and 2,086 female inhabitants in 4 urban and 7 rural areas. Each case was selected randomly to represent 1,000 inhabitants referred to the census in 1980. Formalin-Ether sedimentation technique was employed to concentrate the cysts and one Lugol's iodine stained smear was examined for each case. The results were summarized as follows: The cases who passed out protozoan cysts of any kind were 9.1 percent out of total 4,116 examined, and cumulative positive rate was 11.0 percent. Among the positive cases, 16.5 percent were infected by two or more species of protozoa. Total 5 species of cysts were detected and the positive rates were as follows; Entamoeba histolytica 1.4 percent, E. Coli, 4.9 percent, Endolimax nana 2.5 percent, Iodamoeba butschlii 0.4 percent and Giardia lamblia 1.9 percent. The cyst positive rates varied greatly by the surveyed area. The positive rate in rural area was 11.6 percent compared with 5.7 percent in urban area. The highest rate was found 14.5 percent in Gurye Gun (County) and the lowest 3.6 percent in Mogpo Si (City). Female showed much higher positive rate than male as 11.8 percent compared with 6.4 percent and the cumulative rate 14.2 percent and 7.6 percent respectively. By age group, the rate was highest as 13.9 percent in 40-49 years and next 12.5 percent in over 60 years group. The cyst prevalence rate diminished remarkably in Jeonlanam Do compared to previous records. However, the finding that 20.2 percent of females of 40 years were the carrier of protozoan cysts was an important information in public health point of view.
