[Diaplacental passage of Sarcocystis antibodies in man and rats (author's transl)].

Sera of babies up to the age of 3 months were tested for Sarcocystis antibodies using the indirect immunofluorescence test (IIFT). In addition titre of the Sarcocystis antibody level of litters born to serologic Sarcocystis positive mother rats was compared to those of their mothers. The results are as follows: 1. 45 (= 14.6%) out of 308 sera from babies up to the age of 3 months reacted positively in the Sarcocystis antibody test. 2. 28 (= 62.2%) out of the 45 positive sera were from babies up to 2 weeks old, 13 (= 28.9%) were from babies older than 2 weeks but not more than 4 weeks old, and 2 (=4.4%) each were from babies whose ages ranged from 4 to 8, and 8 to 12 weeks respectively. 3. These babies acquired their Sarcocystis antibodies which decreased in the first 3 months of life from their mothers. 4. Litters born to serologic Sarcocystis positive mother rats also demonstrated Sarcocystis antibodies. The titres of these antibodies were at the same level as their mothers' at birth but reduced gradually so that most of these young rats were negative at the age of 3 months. 5. Suckling rats born to Sarcocystis negative mothers but positive fathers remained negative. 6. Serologic positive mother and father rats still demonstrated Sarcocystis antibodies in the sera at a time when their litters have become negative. 7. Sarcocystis antibodies could be passed onto the newborn from their positive mothers in both man and rats. 8. These antibodies were probably passed onto the newborn through the placenta but their passage through the colostrum and the mother's milk cannot be ruled out.