Pathogen: There are three different worms that can cause elephantiasis. The most common being Wuchereria bancrofti, and the other two are Brugia malayi and Brugia timori.
Kingdom: Animalia; Phylum: Nematoda; Class: Secernentea
Category of Pathogen: Nematode
Symptoms of Infection: *Initial symptoms such as: fever, shaking chills, sweating, headaches, vomiting, and pain may occur due to the body’s allergic reaction to excretions and secretions of the worm. *Long term symptoms include: swelling and enlargement of the arms, legs, head, genitals, and breasts due to damage of the lymphatic system by the parasitic worm.
Primary host: Human
Other host: Mosquito (resevior host)
Route of transmission: An infected person carries the worm in the lymphatic system. The adult worms begin producing many live embryos called microfilariae. The microfilaria make their way to the blood stream where they can be ingested by a feeding mosquito. The infected mosquito then feeds on the blood of an uninfected person, passing the microfilariae into the persons blood stream where they make their way to the lymphatic system to mature.
Prevalence: Currently elephantiasis affects about 120 million people. About 2/3 of the infected people are in India and Africa. The remaining 1/3 of infected people live in South Asia, the Pacific and the Americas. In these endemic communities up to 10-50% of men and 10% of women can be affected.
Generation time: Once the larvae enters into the blood stream, depending on the species of worm, development can take anywhere from a few months to over a year. They grow in size anywhere from 1-4 inches long. After maturation the worm can survive in their human host for an average of three to eight years. Some cases have gone up to 20 years and in one case 40 years!
Morbidity rate: Currently there are about 120 million people infected with about 40 million that are seriously incapacitated and disfigured.
Is it preventable? How?: The treatment drug currently used is diethylcarbamazine (DEC), which can also be used to prevent infection. It has also been shown to reduce the number of carrier insects in a particular area. Other forms of preventability are the use of insecticides, insect repellents, and bed netting.
Does the disease trigger long lasting immunity?: No, the body does not build an immunity to the worm after the person is no longer affected, only continuing to take DEC or other treatment drugs can prevent a re-occurence.
When was the pathogen first described and is there evidence that it was around much earlier than that?: The term Elephantiasis was first used by Celsus (30 BC-50 AD). Throughout time there have been many paintings, sculptures, ect.. that depict the effects of this disease. It is thought that the soldiers of Alexander the Great broght elephantiasis to southern Europe and northern Africa when returning from India. The crusades are said to have brought it to northern and western Europe. Later it was introduced to the Americas through African slave trade. In 1866 Otto Wuchereria first described the embryo form of a worm, that in 1876, Joseph Bancroft identified in cases of filarious disease.
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What is the economical impact of the disease?: In the affected areas the economical impact is great. People who have and are disfigured by the disease often cannot work or are extremely limited in their abilities. They have trouble standing for long periods of time and it can be extremely dificult to walk at all.
The coolest thing about the disease: I think the coolest thing about elephantiasis is that research on the worm that cuases it may help in preventing organ rejection after a transplant. Scientistis have mapped out the genome of the worm Brugia malayi, which causes elephantiasis. Whats cool about these worms is the chemicals they release to lessen the response of the immune system. By studying the genes associated with different functions of the worm, there might potential in finding a medicine that can reduce the number of rejected transplanted organs. Pretty cool!!
Citations
Dunham, By Will. “Genome Deciphered for Elephantiasis-causing Worm | Reuters.”Business & Financial News, Breaking US & International News | Reuters.com. 20 Sept. 2007. Web. 01 Sept. 2010. <http://www.reuters.com/article/idUSN2042109920070920>.
“ELEPHANTIASIS.” The Human Marvels. Web. 02 Sept. 2010. <http://thehumanmarvels.com/?p=119>.
“Elephantiasis – Definition of Elephantiasis in the Medical Dictionary – by the Free Online Medical Dictionary, Thesaurus and Encyclopedia.” Medical Dictionary. Web. 01 Sept. 2010. <http://medical-dictionary.thefreedictionary.com/elephantiasis>.
“Lymphatic Filariasis Facts.” Directors of Health Promotion and Education. Directors of Health Promotion and Education. Web. 01 Sept. 2010. <http://www.dhpe.org/infect/Lymphfil.html>.
“People’s Knowledge and Attitude to Elephantiasis and Its Prevention in Southwest Ethiopia | International Journal of Health Promotion and Education | Find Articles at BNET.” Find Articles at BNET | News Articles, Magazine Back Issues & Reference Articles on All Topics. Web. 02 Sept. 2010. <http://findarticles.com/p/articles/mi_6793/is_4_44/ai_n28405791/>.
Hajdu, Steven I. “A Note from History: Elephantiasis.” Annals of Clinical & Laboratory Science 32.2 (2002): 207-08. Print.
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