Spiruroids - Filarioids Flashcards
Filarioidia featuress
- Adults not in GI tract: feed on blood and lymph - primarily viviparous (L1=microfilaria) - indirect LC - long adults (10cm-1m)
General LC of filaria
Infective stages
L1 infective to fly
L3 infective to host
Zoonosis to humans?
Adults block lymphatics -> lymphoedema
secondary infections skin (elephantitis)
Program to eliminate by 2020 -> mass administration of albendazole + either ivermectin or diethylcarbamazine
Disease caused by filarioidea in humans
Onchocerca volvulus -> river blindness
Prurititic dermatitis
Death in eye - inflammation -> blindness
Filariodea of equids
Onchocerca cervicalis (nuchal lig)
Oncocerca reticulata (exotix; flexor tendon)
Onchocerciasis in horses
- Dying microfilaria in dermal tissue -> pruritic dermatitis
- skin of the ventral midline, face, neck, withers, forelegs and abdomen.
- scale, crusts, ulceration, alopecia and depigmentation
- Qld itch or neck worm
Diagnosis of Onchocerciasis
- Skin snip (warm saline) or biopsy
- response to treatment
How to treat Onchocerciasis?
- Ivermectin and moxidectin agains microfilaria
- Permethin pour on
Filarioidea of cattle
Onchocerca gutturosa (nuchal lig)
O. gibsoni (Dermal tissue of brisket)
O. lienalis (gastrosplenic ligament)
Stephanofilaria stilesi (dermis of ventral thorax)
Impact of Onchocerca gibsoni?
- Economic; carcass trimming and condemnation
Lesions from Stephanofilaria stilesi
- lesions on ventral thorax and abdomen
- ulcerated and exdative (attracts flies)
- chronic -> hyperkeratosis, pigmented
Diagnosis of filarioids in cattle
- ask abattoir whats common in the area
- skin snip, macerate in warm salin
- Stepanofilaria mff are timy (~50um) compared to onchocerca and Seteria (>230 um)
Control of Sephanofilaria
- no antihelmintic against adults
- Northern and coastal NSW
- Buffalo flies can’t live off host >1-2 hours
- Walk through fly trap
- dung beetles (control vector)
- Synthetic pyrethroids or OPs
