Schistosoma mansoni:
http://www.bing.com/images/search?q=schistosoma+mansoni&FORM=HDRSC2#view=detail&id=7C7C53DD1CB517210E8E9FC8B8879EBE309B64F4&selectedIndex=8
This species of schistosoma is known to cause the disease schistosomiasis. There are two variants of schistosomiasis, one type affects the urinary tract and the other affects the intestinal tract. The schistomosomiasis that affects the urinary system results in a damaged bladder, ureters and kidneys. The intestinal variant causes enlargement of the liver and spleen. It also causes hypertension of blood vessels found in the abdominal region, while damaging the intestine. Schistosomiasis causes a rash, a fever, chills, a cough and muscles aches.
The organism enters the host's body through the skin during its larval stage. It makes its way into blood vessels that surround the intestine and matures into an adult. The male and female organism mate by the female being held by the male. Thousands of eggs are released by the female worm and will become lodged in tissue or leave the body with waste. The eggs, still trapped within the host, cause an immune reaction.
In order to treat the disease, medication is issued. The drug used is called Praziquantel, which is taken for one to two days. There is no vaccine available, it is advised that people traveling in areas where the worm is present avoid swimming in freshwater. Countries where the parasite is found try to control the snail population which spread it. The snails are an intermediate host for the worm before infecting humans.
Schistosoma mansoni has not been recorded in the United States. It is most commonly found in Brazil, most African countries, India, China, Malaysia and the Middle East. It is the second most common parasitic disease below malaria. Currently, there are 200 million people infected with the schistosoma mansoni worms in the world.
Sources:
http://www.nhm.ac.uk/nature-online/species-of-the-day/scientific-advances/disease/schistosoma-mansoni/index.html
http://www.cdc.gov/parasites/schistosomiasis/gen_info/faqs.html
Fasciola hepatica:
http://upload.wikimedia.org/wikipedia/commons/3/30/Fasciola_hepatica.JPG
The common liver fluke, (Fasciola hepatica), is known to cause the disease fascioliasis, can be found in areas where livestock, such as sheep and cattle, are raised. It can be found on all continents except and in over 50 countries. Cases are most abundant in developing countries where water quality isn't very sanitary.
The parasites infect humans when infected watercress or other plants are consumed. Larval flukes make their way into the bile ducts, there they mature and begin producing eggs. Symptoms of a Fasciola infection arise at different times depending on the person. It can take a few days to a few weeks for symptoms to begin presenting themselves in the victim. Signs of infection include nausea, vomiting, abdominal pain, fever, rash and difficulty breathing. The disease is treatable using the drug triclabendazole, which has a high success rate.
In order to control the parasite, people are advised to not eat raw watercress and other water plants. Travelers should avoid eating or drinking in areas where sanitation is bad. Countries or regions will enforce a control on the grow and sale of water plants.
Sources:
http://www.cdc.gov/parasites/fasciola/
Taenia saginata:
http://missinglink.ucsf.edu/lm/virus_and_parasites/images/Taenia_saginataadult.jpeg
Taenia saginata is a tapeworm that infects cows and humans. The worm causes taeniasis, which exhibits constipation, diarrhea, dizziness, headaches, loss of appetite, nausea, weight loss and stomach aches as symptoms. Diagnosis of the disease is done by identifying the eggs and proglottids. A stool sample will show this after three months after the start of the infection.
Taeniasis occurs all over the world, but is more prevalent in Africa, Eastern Europe, Latin America and the Philippines. In order to prevent the disease, it is advised that beef be cooked above 60 degrees Celsius until well done. Freezing meat below -5 degrees Celsius has the same effect. Farmers are advised to keep in mind where their cattle are grazing. Cattle that eat in areas where their food source could be contaminated with human waste are at risk of being infected.
Sources:
http://www.parasitesinhumans.org/taenia-saginata-beef-tapeworm.html
