Schistosoma mansoni mother sporocyst and eggs

The three objects shown are (left) a pulsating mother sporocyst, (top) an egg containing an active miracidium and slightly below that and to the right, an unembryonated egg.

During the Schistosoma mansoni life-cycle, eggs (note the lateral spine that is diagnostic for this schistosome species) are passed out of the human with the feces. On contact with fresh water, eggs hatch to release miracidia (a single miracidium is seen within the egg at the top of the screen) that then seek out the snail host and actively penetrate it. Upon entering the snail the ciliated plates surrounding the miracidium and that allow it to swim are released (note the small fuzzy circular objects in the movie ) and the miracidum transforms itself into the next parasite stage known as the mother sporocyst. Each mother sporocyst divides asexually to produce daugther sporocysts which, in turn, asexually produce cercariae. Cercariae are released from the snail into water and can invade skin to initiate the disease schistosomiasis in humans. The time taken after penetration of the miracidium to release of cercariae from the snail depends on environmental cues such as temperature and snail species, but is usually a few weeks. Speeding miracidia can be seen occasionally passing through the shot.

Category:

Education

Tags:

• parasite
• worm
• schistosome
• tropical
• disease
• medicine

[gadionson1]

that's bacteria work.... :-(

[Lrdvltr]

These should be exterminated. They serve no purpose on earth.