Incidence of parasites found on vegetables collected from markets and vegetable gardens in Taegu area.

A parasitic survey on vegetables collected from markets and vegetable gardens in Taegu area was conducted for the discovery of human parasitic eggs and larvae. Three species of vegetable, lettuce (Lactuca sativa), young radish(Raphanus sapivus) and Chinese cabbage (Brassica pekinensis) were selected. All vegetable leaves were washed with a hard brush, and then species of parasites and the approximate mean number of parasitic eggs per 200 grams of vegetable leaves were investigated. When vegetables collected from markets were examined, 5 species of parasite eggs (ascarid, trichurid, Trichostrongylus, Clonorchis and hookworms) and 2 larvae (filariform and rhabditoid ) were found. Furthermore, a number of eggs and larvae of undetermined species were also observed. Of the parasites studied, ascarid egg was found to be highest (49.0%), followed Trichostrongylus egg(18.0%) as well as filariform larva of hookworms (19.7%), and the least often observed was rhabditoid larva of hookworms(0.7%). The recovery rate of parasites among lettuce, young radish and Chinese cabbage collected from markets ranged from 23.2 to 91.9 percent and was similar to that from vegetable gardens, where Chinese cabbage showed the highest (91.1%) and lettuce being next(49.0%) in positivity of ascarid eggs. In the case of filariform larva, the rate of Chinese cabbage was twice as high as that of lettuce and young radish. There was a significant reduction in the rate of filariform larva, suggesting that a single washing of vegetables at the vegetable washing stand would reduce the number of parasites attached to vegetable leaves, when young radish washed at the stand was compared with that unwashed. In the monthly rate of parasites recovered from young radish, there was significant fluctuations between the eggs and filariform larva of hookworms. The mean number of ascarid egg per 200 grams of vegetable was 7.5 in young radishes, 3.1 in lettuces, and 0.5 in Chinese cabbages, in decreasing order. It is noteworthy that young radish contained more than 10 times more than Chinese cabbage. These results would seem to indicate that one of the important routes of infection is due to consumption of pickled young radishes in summer than pickled Chinese cabbages in winter.