Schistosomiasis life cycle.

<p>The most common species found to be pathogenic to humans; and <i>Schistosoma (S.) haematobium, S. mansoni, S. japonicum</i><a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003229#pntd.0003229-Verani1" target="_blank">[73]</a>. Eggs are excreted through faeces, urine and possibly through vaginal discharge from infected individuals, may hatch if they come in contact with water, releasing miracidia that infect fresh water snail hosts where they multiply, producing free-swimming cercariae that eventually may penetrate the skin of human hosts. The cercariae mature in the portal vein and migrate to venules draining the intestines, or the urinary and genital tracts, where they may deposit up to 300 eggs every day. Some of these eggs will be trapped in the tissues inducing a localised host response, while others will penetrate the vessel wall and the mucosa of the intestines, the bladder or the genitals, subsequently excreted in faeces, urine or vaginal discharge into fresh water in order to continue the parasite life cycle. This figure shows the venous plexus of the bladder only; however, the venous plexi surrounding the genital tract is also affected. (Source: CDC-DPDx, Atlanta, United States).