Neglected Tropical Parasites

A) Elephantiasis:  Tissue Roundworms... Distribution of Elephantiasis in Africa/Asia 2008       
    (1) Scientific name ... Tissue Filariasis caused by..
Wuchereria bancrofti ,     Animal Helminth Tissue Roundworm (larvae), filarial nematode
Brugia malayi     Animal Helminth Tissue Roundworm (larvae), filarial nematode
*Onchocerca volvulus  , Animal Helminth Tissue Roundworm (larvae),filarial nematode (see *)
**Dirofilaria immitis ,  Animal Helminth Tissue Roundworm (larvae), filarial nematode
***Filariasis, Loaiasis, The African “Eye Worm”
(2) Common names
Filariasis;  Big Leg,  Elephantiasis
(3) Life cycles including Hosts/Vectors/Reservoir of infection (a source of infection in animals "other" than a host where parasite persist and maintain their ability to infect)...| |
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     (a) Alternate host (asexual reproductive host)...
    Mosquito, bites an infected human and ingests microfilariae, microfilariae bore through mosquito stomach and thoracic muscles and develop into larvae
    (b) Definitive host (sexual reproductive host)...
Man….infected mosquito bites human, larvae emerge from mouthparts onto skin and enter body through the bitewound, larvae migrate to lymphatic vessels and lymph nodes then mature, adult worms mate and release microfilariae which migrate to peripheral circulation between 10 pm and 4 am (particularly malayi when mosquito’s will bite) remaining in tiny capillaries of lungs during the day (when mosquito’s are not around), the death of the adult worm results in calcification and inflammation and closure ofthe lymph vessels blocking drainage, repeated infection  causes elephantiasis  
     (3) Vector (the "way" the parasite is "brought" to humans - usually an insect)
Vector is Mosquitoes of the genera Aedes, Culex, Anopheles and Mansoni
    (4) How does each parasite "hide" from the human immune system (they are large!)
Produce enzymes that "cut" antibodies
    (5) Which "form" of theparasite's life cycle does the most DAMAGE to us...
The adult female
    (6) What potential do we have to control the parasite by treatments, vaccines, vector control or other means...
a) Ivermectin (disease control) – puts the adult female on birth control, prevents transmission of the disease
b) Diethycarbamazine (drug of choice) – kills the adult worm may require antihistamines or corticosteroids tolessen allergic response and prevent allergic emergency 
 c) Diethycarbamazine + Suramin – same as above but more toxic  
 d) antibiotic treatment for secondary infection and blood poisoning 
 e) pressure bandages for early elephantiasis surgical removal of excess tissue      
 f) Early detection and treatment to eliminate carriers in man  
g) Vector control  by less toxic insecticides,personal repellants. genetic control of the vector?          
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*(B) RIVERBLINDNESS
    (1) Scientific name
              Onchoceriasis caused by..
Onchocerca volvulus  , Animal Helminth Tissue Roundworm (larvae),filarial nematode
   (2) Common names:
Riverblindness 
    (3) Life cycles including Hosts/Vectors/Reservoir of infection (a source of infection in animals "other" than a host where parasite persist and maintain their ability to infect)...

             (a) Alternate host (asexual reproductive host)...
Simulium fly (blackfly) breeds in fast running water (river), the black fly bites aninfected human and ingests microfilariae, microfilariae bore through the fly’s stomach and thoracic muscles and develop into larva
(b) Definitive host (sexual reproductive host)...
Man….infected blackfly bites human, larvae emerge from mouthparts onto skin and enter body through the bite wound, the larvae migrate in the subcutaneous tissue, form nodules and slowly mature into adult worms, After...