Hundreds of cases of infantile hookworm disease which shows bloody stools, melena, anorexia, listlessness and oedema, have been reported in China since the 1960s. Hookworm eggs were detected in due course in the faeces of the reported cases. With the exception of a single worm identified as Necator americanus, all the adult worms expelled following chemotherapy or examined at autopsy were Ancylostoma duodenale. Many children showed clinical manifestations and eggs in their faeces on day 1-26 after birth, and more cases occurred within 3 months of birth. Evidently, these infections were mostly transmitted from the mothers by transplacental and/or transmammary routes.