Gross Human Parasites IV - Sparganosis for the Flesh-Lover

Keeping pets at home? Love sushi? Enjoy frog-congee? 

Sparganosis is a parasitic infection, the culprit is a type of tapeworm belonging to the genus Spirometra. Mammals such as dogs, cats and raccoons are the definite host (final host) of the parasites. 

Copepods, Frog, Cat. (The first, second and definite hosts)

The adult Spirometra living in the intestines of their hosts lay uncountable eggs which discharge during hosts' defecation. The eggs are then consumed by copepods, the first intermediate hosts; amphibians such as snakes and frogs preying on copepods are the second intermediate hosts. Within the first intermediate hosts, the eggs hatches and the larvae live in the body cavities of copepods; after passing to the second intermediate hosts, the larvae continue to proliferate and penetrate into the muscles and subcutaneous tissues of the hosts. The second intermediate hosts of this parasites are eventually consumed by wild carnivores such as dogs and cats, and the parasites mature in their definite hosts and complete their life-cycle. 

And how do human get Spargonosis? 

Human are actually the accidental hosts of Spirometra (or maybe not accidental). 

• consumption of raw water from rivers or lakes 
• open wounds on body contacted with Spirometra sources such as animal feces or raw flesh 
• consumption of uncooked or not-fully-cooked flesh 

Once infected, the parasites will move to various organs such as eyes and brains of the patients or subcutaneous tissues in various body parts. No symptoms will be seen from the beginning, and eventually as the parasites grow, bulges (nodules) will develop on the infected regions along with pain. For infection in the eyes, patients' eyes will bulge out. For infection in the brains, neurological symptoms such as loss of motor control can occur. 

A boy with ocular Sparganosis
Source: click here

Surgical removal of adult Spirometra from eye. 

It has been reported in China rural areas that villagers believed in old traditional methods of applying raw frog flesh to wounds to speed up recovery, and thus resulted in being infected by Spirometra. Majority of human Spirometra infection cases occur in Japan, Korea and China.

Retracting an adult Spirometra from a frog.

Antibiotics have been given to patients infected with Spirometra, however this is not really beneficial as a cure. The best way to get rid of the parasites is through surgery. 

The Ultimate Body Invaders

In the world of Nature, every organisms are trying very hard to win the game of survival. In order to win the game, some come up with an extraordinary method---to invade another kind and manipulate the host to create a condition favoring the survival of the invaders, while putting the hosts in great danger. The following are 5 ultimate body invaders that adopt the unique mechanism to ensure the survival of their species. 

Cordyceps 

Cordyceps invaded host. 

Cordyceps are fungi from the genus ascomycete fungi, among which there are a lot of different species. The fungus parasites on insects and different species parasites on different hosts. As the cordyceps fungus infects an insect host, its mycelium (fungus part) replaces the host's body tissues. The fruiting body of the fungus will eventually puncture the host body and protrude out to allow the release of ascospores (spores). Many of the times, during the development stage, the fungus manipulate its host such as controlling the insect to climb up a plant and attaches itself there before it dies, ensuring optimal dispersal of the spores of the fungus. Some cordyceps genus are proven to have medicinal properties.  

Paragordius tricuspidatus

Parasitic worm emerging out of cricket.

Paragordius tricuspidatus is well-known for manipulating behaviour of its cricket host. The eggs of this parasitic worms are laid at the river edges where the crickets reside. The microscopic size eggs are ingested by accident by the crickets, and hatch within. The larvae of the worm get nourishment from the host and grow, eventually filling the entire body cavity of the cricket. They can grow up to 10 - 15cm in lengths.  Upon maturation, the parasitic worms are ready to exit the hosts, the worms will induce an abnormal behavior to the cricket hosts --- to jump into the water. Most of the crickets will drown, while some will survive and lead a normal life after the excision of the parasites. After which, the worms will slither out and find its mating partners. The manipulation in behaviours are believed to be cause by a release of proteins that affect the Central Nervous System (CNS) of the crickets.  

Dinocampus coccinellae

Paralyzed ladybug guarding cocoons

Dinocampus coccinellae is a species of wasp that parasites on Ladybug. The female wasp lays one egg in the soft abdomen of the ladybug. After the egg hatches, the larva starts to consume the ladybug's eggs, then the gonads and the body of their host. However the ladybug host is still alive. When the parasites are ready to emerge, they paralyze the ladybug and tunnel out of its body. Then the parasites pupate in a cocoon attaching to the leg of the living ladybug, The ladybug's occasional twitching ward off any potential preys of the parasites,  making the ladybug the "bodyguard" of its parasites. A few days later, the wasps will emerge from the coccoon. 1 out of 4 ladybugs will recover from the paralysis and come back to health after all the cocoons have emptied.  

Leucochloridium paradoxum

Snail with infection.

Leucochloridium paradoxum, a kind of parasitic flatworm, infects a snail and alters the original behaviors and appearance of the snail; after which increasing the chances of the snail being eaten by a bird which is the next and final host of the parasite. To do so, the parasite resides into the translucent eye-stalks (preferably left one) of the snail, altering the normal eye-stalks into yellow-greenish stripes, inducing caterpillar mimicry. Birds do not usually snack on snail, however the altered eye-stalks of the snail, resembling a caterpillar results in birds mistakenly consuming the infected snails. The parasites also cause the snail to be more visible to the birds by making the snails stay under the sunlight instead of hiding in the shade.   

Myrmeconema neotropicum

Normal ants.

Infected ant with red gaster raise up high to mimic wild-berries. 

Myrmeconema neotropicum is tetradonematid nematode parasite that induce berries mimicry in tropical ants. The parasites mate and lay eggs inside the gasters (the hindmost abdomen) of the ants. The infected ants will develop bright red, egg-filled gasters that resemble red berries available in tropical forest. The parasites also cause the weakening of the exoskeleton linking the gasters to the rest of the body of the infected ants. The infected ants will walk with their gasters raise up high, allowing birds to mistaken them as wild berries and pick up the gasters which detach easily from the ant.The parasite eggs will be passed in the birds' dropping and later collected by the tropical ants again.  

Buruli Ulcer - Infection that Consumes Skins

Buruli Ulcer is a disease caused by infection by the Mycobacterium ulcerans. It is one of the most neglected disease in the world, specifically in the developing countries. Mycobacterium (other bacteria of the same family) is also the bacteria that causes tuberculosis and leprosis; however, Buruli ulcer has received the least attention.

Infection of this disease occurs mainly in tropical areas such as Australia, West Africa, Southeast Asia and New Guinea. Among which, this disease has the largest impact in developing countries, mainly due to the lack of knowledge in the disease.

It has been reported that the mycobacteria strives within aquatic environments (such as small aquatic animals, biofilms). Transmission mode to humans is still under investigation. Thus, Buruli ulcers usually occurs near water sources, infecting children under 15 years mainly. There is no evidence that this disease can be transmitted from person to person.

A young boy with Buruli ulcers
Picture Source: click here

Symptoms in General

Buruli ulcer begins with a painless mobile swelling in the skin (any part of the body). The more severe infection can be painful. Buruli ulcer is a long term, necrotizing disease that slowly destroys the skin and soft tissue by the toxin secreted by the mycobacteria.Without treatment, massive ulcerations take place and if the bone is affected, gross deformities will be the consequence.  If the ulcers develop on the limbs, the movement of the patients will be greatly restricted; even after the lesions have healed, the massive scarring will affect the mobility of the patients. In more severe cases, lifetime disabilities are norm in the patients. Can you imagine the pain the patients are enduring?

Treatment And Prevention

The most efficient treatment of Buruli ulcer is the surgical removal of the ulcers. For disease in more advanced stage, prolonged treatment with skin grafting will be necessary. However, surgical practice is scarcely available in developing countries. A combination of antibiotics can be used to reduce the requirement for surgery.

Bacille Calmette–Guérin (BCG) vaccination has been observed to provide short-term protection against the disease. Although only limited protection is available, it will still be useful by ensuring a complete coverage of this vaccine in the heavily affected regions. Once again, people in developing countries have very minor chances to receive such vaccination due to extreme poverty as well as lack of knowledge in diseases.

Noma - The Disease that Destroys Smiley Faces

There are many unfortunate people around the world, especially people in the developing countries. They do not even have the basic food and necessities to allow them to live healthily. Horrifying diseases roam, leaving the people in great agony. 

Gangrenous stomatitis, commonly known as Noma, is a condition whereby the mucous membrane of the mouth and other tissues of the patients are destroyed. This disorder usually occurs in developing countires where there is malnutrition and poor cleanliness. This is also more often seen in young, severely malnourished children of young age (2- to 5-year-old).  

Once infected, Noma causes rapid tissue destruction, the gums and cheeks become inflammed and ulcers develop. The ulcers and destroyed tissues lead to severe breath odor. Infection of the tissues then spread to the skin, lips and cheeks, eventually destroying the soft tissue and bone around the infected regions. The infection will lead to deformities and loss of teeth. The patients' facial features will be severely disfigured and the normal functions of the jaws will be greatly impaired. 

The actual cause of the disorder is still not known. However, it might be due to a type of bacteria. Antibiotics and improved nutrition can aid in controlling the disorder. The condition can be fatal in some cases if left untreated; on the other hand, the condition might heal eventually even without treatment. To treat the disorder, surgery might be required to remove the destroyed tissues, and plastic surgery will be required to reconstruct the facial bones. Patients recovered from the disorder will have horrifying scars on their faces. 

This might look horrifying to you, do bear in mind that this kid
do not have a choice, if he does, a life free of disease is all he desires.

To reduce the risk of Noma, it is important to improve hygiene level and nutrition. However, sad to say, these two basic preventions are often the hardest to fulfill in most of the developing countries.