Parasitic worms: strategies of host finding, recognition and invasion

摘要: Many parasitic worms enter their hosts by active invasion. Their transmission success is often based on a mass production of invasive stages. However, most stages show highly specific host-finding behaviour. Information mechanisms available mainly for trematode miracidia and cercariae nematode hookworms. The larvae find recognise hosts, in some cases even with species specificity, via complex sequences behavioural patterns which they successively respond to various environmental host cues. There surprisingly high diversity host-recognition strategies. Each parasite finds enters its using different series For example, schistosomes the human skin recognition sequences. strategies may reflect adaptations distinct ecological conditions transmission. Another question how, after invasion, paths through host's tissues very microhabitats. Recent data that migrating can follow local chemical gradients blood compounds, but long-distance navigation within body still remains puzzling. complexity, specificity suggest finding are important determinants evolution life cycles.