Interactions

                                        Who does this parasite interact with? Let's find out! 

     The parasite Onchocerca volvulus does not have a large interaction with many species. The blackfly carrying this parasite interacts with a host in which it infects. This species does not provide food for other organisms nor does it serve as a host to other organisms. The worms share a mutualistic and endosymbiotic relationship with the bacterium Wolbachia, which means that the bacterium lives within the worms and both organisms are benefiting (Tamarozzi 2011).
     Onchocerca volvulus has a major effect on us as humans. This parasite causes the disease of onchocerciasis, which infects nearly 17.7 million people around the world. This disease does not cause death, but can severely harm an individual. There are no positive outcomes if one is infected with this parasite. The negative effects, on the other hand, can range from minor inflammation to the severity of blindness. The minor inflammation a person may receive if infected is caused by live microfilariae. If the microfilariae are dead, it can cause intense itching, skin discoloration, thickening and cracking of the skin, severe dermatitis and loss of skin elasticity. An early sign of infection are large lumps seen in the skin. What commonly happens is the microfilariae move into the eye and when they die it causes many of the listed symptoms, which usually leads to blindness. This disease, which seems to affect males more often than females, disturbs the vision of 500.000 people and 270.000 people become blind (Dalton 2001).
     The adult worms get their nutrients from feeding on blood or by absorbing through complex cuticles. These worms are ingested more often than preyed upon directly. Death rates for egg and larval stages are high due to the parasite not being able to reach a host in time. These flies breed in river environments because of the high oxygen tension in the water (Onchocerca volvulus: The Causative Agent 2000).

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