Parasites Turn Out to Be Tiny Jellyfish?

Parasites are one of those topics that are equal parts fascinating and disgustingly horrible; a combination that explains the popularity of the television show Monsters Inside Me and the dozens of bot fly maggot removal videos on YouTube.

Some recent news stories have included a man who was infected by a tapeworm with cancer which resulted in his death from tumors comprised of cancerous tapeworm cells and the little boy who had a snail growing in his knee (strictly speaking, not a parasitic organism).

If those stories aren't enough to fuel your nightmares and phobias, allow me to introduce you to a peculiar class of parasites, the Myxozoa:

The Myxozoa (etymology: Greek: μύξα myxa "slime" or "mucus"[1] + thematic vowel o + ζῷον zoon "animals"[2]) are a group of parasitic animals of aquatic environments. Over 1300 species have been described[3] and many have a two-host lifecycle, involving a fish and an annelid worm or bryozoan. The average size of a myxosporean spore usually ranges from 10 μm to 20 μm[4] whereas that of a malacosporean spore can be up to 2 mm. Myxozoans can live in both fresh and marine habitats. Early thought to be unicellular, they are in fact multicellular organisms, probably extremely reduced cnidarians.[5] Infection occurs through valved spores. These contain one or two sporoblast cells and one or more polar capsules that contain filaments which anchor the spore to its host. The sporoblasts are then released as a motile form, called an amoebula, which penetrates the host tissues and develops into one or more multinucleate plasmodia. Certain nuclei later pair up, one engulfing another, to form new spores.

These critters have also been found in frogs, birds and shrews and probably similarly live — in one stage or another — in a number of other hosts yet to be described.

Until just the last few years, they were thought to be protozoans, specifically they were placed in the group Sporazoa along with the such delightful organisms as toxoplasma gondii, the behavior altering parasite thought to infect as much as 30%-50% of the world's human population and which are strongly correlated to a significant increase in the risk of traffic accidents.

Now for the shocker (not that shocking though, it's in the title)!

Further genetic study has revealed that they're actually a clade that should placed in the phylum Cnidaria and that their closest evolutionary cousins are the Medusozoa, a clade which includes among other organisms jellyfish and siphonophores such as the Portuguese man o' war!



The above picture is taken from the article Washington Post - Mysterious parasite may actually be a tiny jellyfish gone awry which came across my feed yesterday and inspired me to do a little Internet research. On the left are several individuals of a species of Myxozoa and on the right, a jellyfish cousin which is 2,500x larger.

a reply to: theantediluvian

I was fretting over toxoplasma gondii due to an obviously highly affected friend then I looked at ATS and . . . this thread. Speechless. They have control of my thoughts.

uggggghhh parasites creep me out!!!

and yet, I still eat sushi. *glulp*

I have a symbiotic relationship with my parasites. They promise not to kill me and I promise them all the food they require.

Interesting and thanks...

one thing along these lines, is: anyone else ever notice that they get ... uhm, extra amorous, or 'romantic,' right before they get sick?

From puberty onward, I started to notice I would get more frisky right before I showed symptoms of a cold, right when the illness is most contagious.

I can't help but wonder if it's a mechanism of the infecting critters... it would make some sense and spread them very effectively through a population.

I know a handshake can do the job as well, but wonder.

If it's a known effect of sickness, I haven't come across it before... and it might just be some other biological factor of my immune system, but it sure does seem more than a coincidence and would make some sense, if so.

I suspect the little critters are not just essential for our lives as they digest for us, but they might have more of an effect on behavior than we suspect.

So be nice to parasites... they rely on you and maybe can give back a little somethin' somethin' in return!

originally posted by: intrptr

I have a symbiotic relationship with my parasites. They promise not to kill me and I promise them all the food they require.

Well said, well said.

a reply to: theantediluvian

Aside from gastro-intestinal parasitic virus, bacteria, fungi, and worms; we have to worry about cnidarians? Thank you for contributing to my perceptual education!

Out of pure speculation: I wonder if the burgeoning practice of genetically modifying aquaspecies may possibly result into a higher susceptibility of cnidarian infection in caught fish, or even gene transfer from GMO host fish to the cnidarian parasites causing mutant behavior and toxic byproduct.

...could other parasites develop cancer and transfer the malignant cells to humans?
From your OP source

Just freaking WOW, man. Just think about the global chemical war being waged on the microbial beings. Millions of acres are sprayed with anti microbial poisons because it is common practice to splatter farmland with human feces!

So the microbes are getting cancer and living in our guts making us cancerous, as well.

Eat good food, kids. Lots of fiber.