Nematodes

Microbiology

• Wuchereria and Brugia (and Loa Loa) all have a sheath. Onchocerca is only pathogenic nematode that doesn't have a sheath.

Lymphatic filariasis

• Pattern of nuclei in the tail (Loa Loa goes all the way to the tail, others don't). Draw blood at midnight for lymphatic filariasis (elephants come out at night). Can also give small dose of DEC and then sample a few hours.
• Stain blood with Giemsa for microfilaria. Treated with DEC +/- albendazole.

Onchocerca

• Onchocerca transmitted by black fly Simin....
• Subcut lumps and bumps, skin thickening and hyperpigmentation, eye involvement with dense cataract. Ivermectin every 6 months for 10 years, but rule out Loa first.

Loa loa

• Crysops? transmits it. Eyeball with worm is almost always Loa. Calabar lump sp? In West Africa, after Crysops bite. May be on and off for years. If going to treat Onchocerca with ivermectin, need to rule out Loa, which can cause fatal encephalitis.

Guinea worm

• Dracunculis. Spread through water, needs to life cycle through water borne Cyclops copapods? Now only present in small number of areas, down to very few cases, through clean water control.
• May also be maintained in dogs, which may make eradication more difficult.