[Studies On The Inducing Possibility Of Human Visceral Larva Migrans Associated With Eating Habit Of Raw Liver Of Domestic Animals].

To observe the possibility of human visceral larva migrans due to eating of raw liver of domestic animals, especially of cattle, and also to serve as a good reference for adequate sanitary measures, the investigation survey was carried out from May 1975 to May 1976. From the subjects of a l,048 inhabitants (male 558, female 490) in five localities including two Provinces and three different cities, food habit was studied by questionnaire mannual. Larvae isolated from liver tissues of cattle, and pig were identified. Experimental observation on the chicken and mice infected with Toxocara canis was undertaken to draw a assumption of possibility inducing human visceral larva migrans. The results obtained from the present study are summarized. 1. A part of Korean people has the habit to eat the livers of cattle, fowl, pig and dog raw. Eating rate of raw beef liver was 37.8% out of l,048 inhabitants, and its rate was higher markedly in male(57.7%) than in female (15. 1%), and the highest rate among the group of 31-40 years old. Eating rate of raw liver of fowl was 5.9%, pig 5.3%, and dog 2.5%. 2. Larva recovery rate from beef liver was 11.8% out of 195 samples and 72.0% of total detected 1arvae were identified as Toxocara(=Neoascaris) vitulorum. From pig liver, larvae of nematoda were found in 6.4% out of 109 samples but no larva was detected from 120 fowl livers. 3. Larvae detected from one-half of tissues and organs of infected chicken with about 2,000 Toxocara canis eggs were 8-245 in number, and 85-100% of recovered larvae were from their 1iver tissues. 4. Toxocara canis larvae, 45, 31, 42 and 23 in number at 3rd, 14th, 25th and 55th day in one-half of the tissues and organs after infection respectively, were demonstrated from the mice infected with 500 larvae collected from infected chicken liver. Most of the larvae were recovered from the carcass of the mouse. It was approved the larvae isolated from chicken possess infectivity to the mice. 5. Typical eosinophilic granulomatous change was not observed in the liver tissue of the infected chicken at 20th day after infection. As it summarized above, the liver of various domestic animals is the favorite tissue for migration of nematodes larvae. Therefore, the possibility of human visceral larva migrans may be induced due to eating of raw liver of domestic animals.