Taenia solium

Dear Mom and Dad,

I know I’ve always said I would go continue school to become a physician’s assistant, but some opportunities in life you just can’t pass up. I’ve decided to do research in Japan on a tapeworm called Taenia solium. It is in the class Cestoda and is transmitted by eating undercooked pork in poor sanitary conditions (Yanagida et al., 2012). It is fascinating to me because this tapeworm causes taeniasis, an intestinal infection and cysticercosis, the infection of various tissues in the body of humans (Yanagida et al., 2012). This is an extremely dangerous, growing problem in the world that is not being researched enough. 

T. solium is the main source of cysticercosis, an infection of humans of the larval stage of T. solium. Humans contract this by accidentally ingesting T. solium eggs from the feces of a human T. solium carrier. This means it is possible to contract cysticercosis in locations without pigs as a reservoir host.  Cysticerci progress in various organs, commonly in brain and eye tissues (Yanagida et al., 2012). T. solium can be found worldwide and research needs to be done.

For this research I would similarly replicate Yangida’s experiment and look back at the cases of T. solium reported in the last 17 years in Japan. I would also study the next 3 cases reported from now. The new cases in the study would be diagnosed using neuroimaging. We would confirm them using ELISA, the enzyme linked immunosorbent assay. This will detect the human antibodies of the parasite (Yanagida et al., 2012). This would give me enough data to prove that T. solium should be included on Japans list of infection diseases. It is a more harmful and dangerous tapeworm than we know. I will write you soon with progress of my research. In the meantime, please have MOM cook all the meat in the house; I know how she tends to cook everything WELL DONE.

With love

Tara

Yanagida T., Sako Y., Nakao M., Nakaya K., A. Ito, 2012. Taeniasis and cysticercosis due to Taenia solium in Japan.  Parasites & Vectors 5:18.

Pechenik, Jan. A Short Guide to Writing About Biology. 7^th: Longman: Pearson Education Inc., 2010. 71-81, 146-7, 157-162, 162-191, 194-201, 201-207 

Killers of Loggerhead Sea Turtles

One of the most influential experiences of my life, and the one which solidified my passion to study biology, occurred in Costa Rica in the summer of 2007. I volunteered for a sea turtle rescue program on the Atlantic side of the country, where a group of cohorts and myself actively searched at nights with headlamps wrapped in red cellophane for sea turtles laying clutches of eggs on the beach. No we were not poachers of these beautiful creatures, collecting their eggs for profit, or benefiting in any materialistic way from the truly unbelievable cross ocean journey these marine reptiles had just accomplished. In fact we were collecting their eggs to move to a hatchery further up the beach, where they would be safe from the washing waves. Deforestation inland of these areas has caused large logs to wash up on the beach, confusing turtles to believe that they are nesting at the high tide line, where their eggs will be safe when really they are tens of meters shy of this safe zone.

 I can vividly remember the first turtle we saw, laboriously digging a deep cavern to lay her eggs after a transoceanic journey of thousands of miles. I could hear the exhaustion in her deep raspy breathes as she plowed the wet sand with what seemed to be completely inept fins. She was so concentrated that she had no idea she was surrounded by amazed high schools mouths agape. As soon as she started to lay I was given the signal for egg collection, and I stuck my bare hands under posterior end. Suddenly I began to catch cups of turtle fluid along with several soft leathery eggs, very similar in size and shape to the dented and deflated ping pong balls any college student is well versed at fixing with a lighter. This moment was an epiphany for me, as I instantaneously understood biological conservation efforts and the serene esthetic beauty of nature. I decided that anyone or anything which harmed or took advantage of these sea turtles and their efforts to reproduce are pure evil. Enter Balaenophilus manatorum (Ortiz et al. 1992) and members of the family Spirorchiidae.

The animal I saw that fateful night in central America was the giant Loggerhead sea turtle Caretta caretta , an animal which can grow to be several hundred pounds. This wonderful animal is endangered because of human and parasitic behaviors coupled with their low reproduction rate and relatively long time needed to reach sexual maturity (20 years) (NOAA). B. manatorum is an ectoparasite which usually attaches to the eyes or flippers of a sea turtle. This behavior in itself can be detrimental to the turtle, if  vision become obscured or damaged due to these organisms, it can result in death. More dangerous and detrimental to sea turtles however are organisms of the family Spirorchiidae. These parasites are member of the class Trematoda and subclass Digenea. These organisms are parasitic flatworms, also known as flukes, which affect all types of vertebrates, and cause many negative consequences in the hosts organisms. (Goodchild and Martin (1969). Usually turtles like the loggerhead pick up these parasites from eating infected mollusks, common hosts for many trematodes in the first part of their life cycle. Most trematodes then have a complex life cycle often using many life stages and hosts. When these parasites gets to the turtle, the infection can affect every system and organ or the body. Pathological effects include but are not limited: to lesions and hemorraging of the heart, aneurysms, infection of the nerves and brain, and skin tumors. (Santoro et al. 2007).

Studying this group of parasites can help save sea turtles and many other vertabrates commonly affected (including humans). Study and research of the genetic differences of this group can give us a unique look at where migrating animals have been in the world oceans, and how recently. On that same note further study may help us understand the effects of global warming on migration patterns of certain affected marine vertebrates. Most importantly however, hopefully it can help us formulate a plan to rid the world of these satanic and heartless parasites, which prey on defenseless cute turtles.

http://www.nmfs.noaa.gov/pr/species/turtles/loggerhead.htm

Eduardo Suarez-Morales, Benjamin Morales-Vela, Janneth Padilla-Saldivar, Marcelo Silva-Briano. (2010) The copepod Balaenophilus manatorum (Ortiz, Lalana and Torres, 1992) (Harpacticoida), an epibiont of the Caribbean manatee. Journal of Natural History. 44:13, 847-859.

Goodchild C. G. and Martin V. L. (1969). Speciation in Spirorchis (Trematoda: Spirorchiidae) Infecting the Painted Turtle, Chrysemys picta. The Journal of Parasitology.55(6), 1169-1173.

Santoro, M. M., Morales, J. A., & Rodríguez-Ortíz, B. B. (2007). Spirochiidiosis (Digenea: Spirorchiidae) and lesions associated with parasites in Caribbean green turtles (Chelonia mydas). Veterinary Record: Journal Of The British Veterinary Association, 161(14), 482-486.

Balaenophilus umigamecolus: A New Ectoparasite Found on Sea Turtles

                Ogawa et al. (1997) identified a new parasite found on the skin of a young loggerhead sea turtle (Caretta caretta) in the Kushimoto Marine Park Center in Japan. The parasite was first identified because the turtle was weak, and had a discoloration on its neck which drew its caretaker’s attention. The discoloration was actually the parasite feeding on its skin (this is known as an ectoparasite). The parasite was washed off of the sea turtle, and filtered through paper to collect over 440 specimens.

                The collected samples of the unidentified ectoparasite were initially thought to be Balaenophilus unisetus, a parasite that is found on whales with a very similar appearance. However, when the newly gathered samples were compared to B. unisetus they were too different to be the same species. Ogawa et al. (1997) continued by describing the measurement and body shapes that were observed in the new ectoparasite, Balaenophilus umigamecolus. There are distinct differences between the sexes that were noted, and the measurement for copepod characteristics were recorded including the body length, the caudal rami, antenna, mandible, and comparison of features on the legs.

                In order to be absolutely sure that Balaenophilus umigamecolus was not the already identified Balaenophilus unisetus Ogawa et al. (1997)spent a portion of their investigation comparing the physical characteristics between the two species. B. umigamecolus is different because it has a smaller size, it has three apical claws on the 3^rd segment of the first leg when B. unisetus only has two, B. umigamecolus has a lack of seta of the 2^nd expod segment of a leg and has a short length of caudal rami (Ogawa et al., 1997). The mentioned characteristics made it clear that they were indeed two separate species.

                There also was a very limited and brief description of the lifecycle in terms of the young, which was particularly interesting. There were limited young found in the numerous specimens collected from the infected C. caretta. There were 10 specimens found clinging to the egg sacks right after hatching that were in the naupilis stage, and only 5 specimens were found in the other copepodid stages and only in the 3^rd, 4^th, and 5^th stages (Ogawa et al., 1997). Even as someone who knows very little about crustacean anatomy, I found this to be interesting because of the implications it has on the life cycle. If there were so many different stages of B. umigamecolus found on the host species, then that means that it is possible that the species spends its entire life on its host species. This fact was supported by the evidence that the nauplius larva has clasping appendages rather than the normal ones of a planktonic nauplius (Ogawa et al., 1997). Many parasites have a more complex lifecycle that involve definitive hosts, intermediate hosts, and reservoir hosts. If B. umigamecolus only needs to be in a single location for its entire lifecycle then it will have continuous access to its host and what it needs to survive.

Work Cited:

Ogawa, K., Matsuzaki K., Misaki H. 1997. A New Species of Balaenophilus (Copepoda: Harpacticoida), an Ectoparasite of a Sea Turtle in Japan. Zoological Science 14: 691-700.

Babesia microti

Babesia is a well know genus of protozoan parasites that were originally described in 1888 by Victor Babes.  They are some of the most abundant blood parasites worldwide today.  However, it was not until 1957 that the first human became infected by Babesia microti (Homer et al., 2000).  B. microti, is only one Babesia species that infects humans, and there are many other members of the genus who are capable of infecting other vertebrates.

Babesia microti  cannot be spread from person to person.  The parasite has a very specific life cycle that must be followed in order for one to become infected.  Infection can occur when a tick, in the genus Ixodes, containing B. microti  sporozoites takes a blood meal from a human or other vertebrate host.  The sporozoites then can enter blood cells, also known as erythrocytes, and reproduce through asexual reproduction. Reproduction in the blood is what causes the physical symptoms of the disease (CDC, 2010).

            The disease caused by B. microti is known as Babesiosis.  Common symptoms of the disease include nausea, chills, fever, headache and body ache.  The disease is most dangerous in people who do not have a spleen, elderly, and people who are immune compromised.  In order to become diagnosed with Babesiosis, B. microti must be observed inside the erythrocytes on a blood smears.  One problem that arises when observing blood smears is that B. microti can often look very similar to Plasmodium,  the malaria causing parasite (Homer et al., 2000).  In addition to this the symptoms caused by Babesiosis are also very similar to the symptoms that coincide with malaria.  It would be beneficial to study B. microti because it infects people in a very similar way to malaria parasites.  Any new prevention techniques or treatments used for one disease may also work for the other.

An additional reason why it may be beneficial to study B. microti is because it shares a vector (members of the Ixodes genus) with another parasite known as Borrelia burgdorferi.  B. burgdorferi is the parasite responsible for causing Lyme disease.   One problem that can arise from this is that because the two parasites share a vector they can often be transmitted together (Piesman et al., 1986).  This means that a victim of the parasites may be diagnosed with one of the parasites while the other goes unnoticed. Both of the diseases caused by these parasites can become dangerous if left untreated for an extended period of time.  By understanding a general description of how B. microti functions it could give strong insight to how other related parasites function as well. 

I was given the opportunity to view an actual blood smear of the organism and I was intrigued.  I wanted to know more about how B. microti functioned and how individuals became infected with it.  After viewing them in infected red blood cells it became more of a reality to me how problematic these parasites can be to people specifically in New England.  Most of the organisms we have learned about in class do not exist in the area  and  therefore becoming infected with them seems unrealistic.  However, B. microti is very common in the New England area and infects a large portion of New England Residence (Roberts and Janovy, 2009).

References

Center for Disease Control and Prevention. Babesiosis. 19 September 2012.(10 July

2012)< http://www.cdc.gov/parasites/babesiosis/diagnosis.html>.[19 September 2012]

Homer, M.J., Aguilar-Delfin, I., Telford, S,R., Krause, P.J., Persing, D.H. 2000.

Babesiosis. Clinical Microbiology Reviews. 13(3):451-469

Piesman, J., Mather, T.N., Telford, S.R., Spelman, A. 1986. Concurrent Borrelia

burgdorferi and Babesia microti infection in nymphal Ixodes dammini. Clinical

Microbiology Review. 24(3):446-447

Roberts, L.S., Janovy, J. 2009. Foundations of parasitology. McGraw-Hill, NY, 169 pp.  

Cyclospora angi…what?????

Imagine it is the year 1990 when the most educated scientists, doctors, and veterinarians knew less, and society beyond less, about the world of parasites than they do today.  The worldwide web was close to non-existent and books were the key source for finding information.  There was no such thing as a “web-based parasite database” like there most likely is today, where the internet is home to virtually everything ever thought of.  With the internet, knowledge is essentially easily accessible. 

Your friend, who is a science fanatic, forgot a hefty library book on your kitchen table, entitled The Journal of Parasitology, from the current year.  You open it up to an article apparently introducing three species of coccidian parasites from heteromyid rodents with locations in Southwestern United States, Baja California, and Northern Mexico.  You have no idea what coccidian or heteromyid means, but you begin to read the associated article in which the scientific wording is enough to scare you.

You start to think the worst, and the idea of parasites sucking the life out of helpless, tiny, host animals is hard for you to swallow.  Then you begin to query and ponder the parasite’s existence.  You wonder if domesticated animals, such as your cat Kit Kat and dog Beau are susceptible to coccidian parasites.  Chills run down your spine when the idea of human hosts pops into your head!  What if the parasite makes its way to New England, where you’re from, and can survive in this type of environment?  Can they cause disease, and can it be treated or is it fatal?  Will we have the ability to break the lifecycle of the parasite?

You snap yourself out of your trance and think, “Maybe it’s one of those kinds of parasites that has a healthy relationship with its host.”  Your imagination has stopped running wild and you begin to see the positive sides to the discovery.  The parasites could even be helpful to science in that they could answer questions about other previously found parasites including host adaptations, pathology, prevalence, and locality.  They can offer more knowledge about potential health hazards comparable to known parasites, and be added to the worldwide known species list. 

You decide you want to learn more about the newly discovered parasites in which you’d never heard of before: Cyclospora angimurinensis, Eimeria chaetodipi, and Eimeria hispidensis.  You are going to read up on their morphology, biochemistry, molecular biology, immunology, phylogenetics, lifecycles, and behavior.  You plan to keep tabs on your findings along the way, but that will be for another day.    

TO BE CONTINUED…

Ford, P. L., Duszynski, D. W., & McAllister, C. T. (1990). Coccidia (apicomplexa) from heteromyid rodents in the Southwestern United States, Baja California, and Northern Mexico with three new species from Chaetodipus hispidus. Journal of parasitology, 76(3), 325-331.

Dracunculus insignis and related species

Dracunculus insignis, originally described in 1858, was first recognized in North America in 1932 in carnivorous mammals. The nematode was first reported as D. medinensis (also known as Guinea Worm, a closely related species which infects humans in Africa and nearby areas) but was later found to be a distinct species. It was suggested that other Dracunculus nematoes previously reported in North America were also D. insignis (Ewing, 1966). Though the species is found in carnivorous mammals including raccoons, dogs, and skunks, the study of this species could lead to a better understanding of D. medinensis infections in humans (dracunculiasis).
Dracunculus larvae are eaten by copepods in bodies of water. When the infected copepods are ingested by larger mammals, the larvae will mature and migrate to muscle tissue causing severe pain and swelling which can be problematic to people in poorer areas who must do strenuous work to survive (Fargo, 2003). Though D. insignis does not infect humans, drugs may be tested on it in infected mammals which may lead to better drugs to combat D. medinensis. Treatment of drinking water to kill larvae-containing copepods, though effective, may not always be feasible in certain areas of the world. Boiling of water or chlorine tablets may be too time consuming or expensive for local people to bother doing. Treatment of the drinking water source may be done, but that will not be permanent as new copepods may be introduced to the water. As soon as a person infected with a fertile female nematode comes in contact with the water, the worm may release larvae into the water, once again infecting the copepods present (Fargo, 2003). Deep wells would create clean sources of water, but would be too expensive for all communities to build.
There is currently no specific drug of choice for treatment of dracunculiasis in humans. The most common way to remove worms is by manually extracting ones which have created a pustule near the surface of the skin by wrapping the nematode around a stick to slowly pull them out. If a cheap, easily accessible drug could be found to kill the worm, then control of the disease may be more feasible. As D. medinensis is not known to have a reservoir host (Bimi et.al. 2005), D. insignis would be the easiest way to study new drugs without having to resort to human subjects.

Works cited:
Ewing, S. A., Hibbs C. M. 1966. Dracunculus insignis (Leidy, 1858) in Dogs and Wild Carnivores in the Great Plains. American Midland Naturalist. 515-519

L. Bimi, A. R. Freeman, M. L. Eberhard, E. Ruiz-Tiben and

N. J. Pieniazek. 2005. Differentiating Dracunculus medinensis from D. insignis,

by the sequence analysis of the 18S rRNA gene.
Annals of Tropical Medicine & Parasitology, Vol. 99, No. 5. 511-517.

Fargo, D. 2003. "Dracunculus insignis" (On-line), Animal Diversity Web. Accessed September 20, 2012 at http://animaldiversity.ummz.umich.edu/accounts/Dracunculus_insignis/

Fargo, D. 2003. "Dracunculus insignis" (On-line), Animal Diversity Web. Accessed September 20, 2012 at http://animaldiversity.ummz.umich.edu/accounts/Dracunculus_insignis/

Fargo, D. 2003. "Dracunculus insignis" (On-line), Animal Diversity Web. Accessed September 20, 2012 at http://animaldiversity.ummz.umich.edu/accounts/Dracunculus_insignis/

Fargo, D. 2003. "Dracunculus insignis" (On-line), Animal Diversity Web. Accessed September 20, 2012 at http://animaldiversity.ummz.umich.edu/accounts/Dracunculus_insignis/