• Question: What is the most peculiar parasite you have come across during your studies?

    Asked by Froyo to Claire, Franco, Koi, Linda, Mark on 15 Jun 2016.
    • Photo: Franco Falcone

      Franco Falcone answered on 15 Jun 2016:

      @Froyo

      A good question – there are many to choose from, odd, odder, the oddest. A few personal favourites of mine:

      Dicrocoelium dendriticum, which I have on microscope slides in my office. It is transmitted from cow or sheep to snail and from there to ants and affects the brain and behaviour of the ant to increase chances of re-uptake by sheep or cows. Mark has described this elsewhere so I won’t delve any longer on this one. It can occasionally infect humans, but it doesn’t cause them to crawl up a grass leave to be eaten by cows. Too bad!

      Another favourite of mine is Dioctophyme renale. This parasite is the largest roundworm which can infect humans, 20-40 cm long (tapeworms get much bigger but they are flatworms, not roundworms). It is caught by eating uncooked fish, or frogs. The adult worms live in the kidney (usually the right kidney), which they eat from inside until there is nothing left except the outer ‘skin’. Infection is extremely rare in humans, mostly found in foxes, coyotes, bears, wolves and other animals.

      Last, but not least, Cymothoa exigua, or tongue-eating louse. This is a parasite of fish. These parasites will eat the fish’s tongue and then replace it, attaching to what is left of the tongue (the stub). It then stays there and feeds on mucus in the fish’s mouth but apparently the fish is still able to eat. Very odd parasite, and the pictures look quite scary. The ‘Alien’ movies spring to my mind when I see these pictures.

    • Photo: Claire Bourke

      Claire Bourke answered on 15 Jun 2016:

      I think that Leishmania parasites are very peculiar; they live inside of macrophages, which are a type of cell that is specialised to kill infections, but some how these sneaky single-celled leishmania paraistes can avoid detection even by this specialised cell type and live very comfortably inside their cytoplasm. One of the ways that leishmania can do this is by disrupting the usual way that macrophages kill parasites by preventing the macrophage from combining the parasite with strong acids in small capsules called ‘phagosomes’.

      Another peculiar thing about leishmania is that they are transmitted by biting insects called sandflies; so they not only infect people, but are also adapted to living inside insects.

      & let’s face it, they also have a really peculiar name!

    • Photo: Mark Booth

      Mark Booth answered on 15 Jun 2016:

      Hi

      Dendrocelium for sure is up there, but what about this one:

      The green-banded broodsac, Leucochloridium paradoxum which infects snails eyes and makes them look like caterpillars that are attractive to passing birds. You can see video of this on wikipedia

      Also toxoplasma gondii – it infects mice and changes their behaviour so they become less afraid of cats. You see some of the most interesting parasites are those that change host behaviour so that the host gets eaten.

    • Photo: Arporn Wangwiwatsin

      Arporn Wangwiwatsin answered on 15 Jun 2016:

      Froyo,

      Many many to choose from. Parasites have some quirkiness which is what I like about them! I shall add to you list, the jumping worms that are parasites of insect.

      This worms are as tiny as 1 mm for when they infect insect. They hang around sitting in a J-like position, waiting for an insect host to come around and then “jump!!” toward the insect. The jump can be as far as 10 times of its length (imaging we jump 10 times of our height…), the worms get into the insect, release bacteria that the worms carry with them, the bacteria quickly kill and liquidify the insect from the inside, the worms eat the bacteria back in, together with the liquidified insect content, and make more baby worms, break free, the baby worms crawl out and look for the next insect to come by, and go another jump!…I’m feeling tingling writing this, but hey, because the worms kill insects so effectively, they have been widely studied for the purpose of using them in farming to reduce the use of insecticide!

      The worms are in a group called “Steinernema” ; a specific example is “Steinernema carpocapsae” …please don’t ask me how to pronounce that…;)

Comments