提供: Vaccipedia | Resources for Vaccines, Tropical medicine and Travel medicine
ナビゲーションに移動
検索に移動
Navigation Menu
|
|
General issues of Vaccine
|
|
General issues of Tropical med.
|
|
General issues of Travel med.
|
|
Trematode (fluke, distoma)
|
|
Onchocerca volvulus
Intermediate host
|
Category
|
blackfly ブヨ, female
|
Latin
|
genus Simulium
|
Inward infection
|
blood-feeding of human
|
Organ
|
midgut
|
Reproduction
|
asexual
|
Course
|
microfilariae has no sheath
- migrate to thoracic muscle
- metamorphoses L1→L2→L3 in thoracic muscle
- L3 migrate to proboscis
|
Detection
|
|
Outward transmission
|
blood-feeding of human
|
Definitive host
|
Category
|
HUMAN
|
Latin
|
|
Inward infection
|
blood-feeding by female blackfly
|
Organ
|
skin, lymphatics, blood, urine
|
Reproduction
|
sexual
|
Course
|
- L3 into adult in subcutaneous
- subcutaneous nodule
- female 33-50 cm (not mm), male 2-5 cm
- live 15 years
- Wolbachia spp. is endosymbiotic bacteria in female uterus, which is essential to survival of female adult
- female produce microfilariae 9 years
- 220-360 µm
- 2 years
- mainly skin, connective tissue, sometimes lymphatics, blood, urine, sputum
- allergy and inflammation resulting in serious skin pruritis (leopard skin, anterior tibia) and keratitis (river blindeness)
|
Detection
|
- skin snipping
- no nocturnality, every time in a day available
- microfilariae has no sheath
|
Outward transmission
|
blood-feeding by female blackfly
|
診断
- Skin snipping による皮膚断片の培養と顕微鏡下観察
- 高浸淫地では有用だが,低感度なので有病割合が低下すると有用性が劣る
- RDT
- Onchocerca vulvolsのIgG4抗体および抗原をimmunochromatographで検出
treatment
- for microfilariae
- ivermectin is effective only for microfilariae
- only one dose of ivermectin 150 µg/kg (both for children and adults) significantly decrease microfilariae load that lasts a year or more
- every 6 month repetition
- If use diethylcarbamazepine (DEC) for onchocerciasis it kills microfilariae inside skin and develops severe allergic reaction against dead microfilariae on skin
- for adult
- doxycycline is effective for Wolbachia resulting in killing of 60% and sterlizing 80-90% of female adult