ABSTRACT
Newborn larvae measure 0.08 mm long by 7 /-tm in diameter and possess a unique sword-like stylet. This enables the larvae to cut an entry hole in the lamina propria and enter the mesenteric lymphatics or capillaries. The newborn larvae subsequently make their way to the arterial circulation and disseminate throughout the host. The larvae are capable of entering any cell type but will only survive in striated muscle. Once within the skeletal muscle the Trichinella larva induce the myocyte to transform into a new cell type, a nurse cell, which sustains the life of the larva (Fig. 6.2). During this metamorphosis the muscle cell switches to anaerobic respiration and, for most species of Trichinella, develops into a cyst of collagen and hyaline. These larva-containing cysts can persist for many years although most calcify and die within a few months.
