Congenital infection with Setaria digitata and Setaria marshalli in the thoracic cavity of a Korean calf: a case report

In March 2010, a 3.5-month-old Korean native calf was anatomized and two nematode worms were detected in the thoracic cavity. The worms were identified and classified by light and scanning electron microscopy on the basis of features at the anterior and posterior parts of the worms. The worms were female Setaria digitata and Setaria marshalli and numerous eggs which contained microfilaria were detected in the uterus of both species. The body lengths of the S. digitata and S. marshalli were 78 mm and 117 mm, respectively. Mosquitoes act as the vector for Setaria nematodes but these are inactivated in winter in Korea. Therefore, we concluded that this case represented setariasis with congenital infection occurring during the summer prenatal stage of life.