Table 1.
Overview of parasitic filarial nematodes pertinent to the antiwolbachial approach.
| Filarial Nematode | Common Host | Wolbachia | Vector | Disease | Location in Host | General Symptoms |
Geographical Distribution | Ref. |
|---|---|---|---|---|---|---|---|---|
| Onchocerca volvulus | humans | yes | black flies, Simulium spp. | onchocerciasis, aka. river blindness | adults in subcutaneous nodules, mf migrate through skin and eyes | skin disease (onchodermatitis: itching, depigmentation), onchocercomata (nodules), blindness, neurological disease (nodding syndrome, Nakalanga syndrome, epilepsy) | sub-Saharan Africa, small foci in South America and Yemen | [1,2] |
| Onchocerca ochengi | cattle (experimental models: mice) |
yes | black flies, Simulium spp. | onchocerciasis aka. onchocercosis | adults in intradermal nodules, occasionally in subcutis | intradermal nodules (noted due to damage to bovine hides); other clinical impact unknown | documented in Uganda and Cameroon; used as a model to study filarial infection | [3,4] |
| Wuchereria bancrofti | humans (~90% of LF cases) | yes | mosquitoes | lymphatic filariasis, aka. Bancroftian filariasis | adults in lymphatic vessels; mf in peripheral blood with varying periodicities | mostly asymptomatic but with time cause damage to lymphatic system and kidneys; chronic symptoms include lymphoedema, elephantiasis, hydroceles;acute symptoms include local inflammation, fevers, secondary bacterial infections, acute filarial lymphangitis, acute dermatolymphangioadenitis |
tropics in Asia, Africa, Pacific, and Americas | [1,5,6,7,8,9,10] |
| Brugia malayi | humans (experimental models: mice, jirds) | yes | lymphatic filariasis, aka. Brugian filariasis |
East and South Asia | ||||
| Brugia timori | humans | yes | Indonesia and Timor-Leste | |||||
| Brugia pahangi | cats, dogs, rarely humans (experimental models: jirds) | yes | Malaysia, Thailand, and Indonesia | |||||
| Mansonella ozzardi | humans | yes | biting midges (mostly Culicoides) and black flies, Simulium spp. | ozzardi mansonellosis | uncertain; adults potentially in subcutaneous tissues/thoracic and peritoneal cavity; mf in blood and skin | potential ocular lesions; mostly asymptomatic but also fever, headaches, itching, joint pain, rash, sensation of coldness in the legs, foot and face edema, keratitis | Caribbean, the Amazon, border between Bolivia and Argentina | [11,12] |
| Mansonella perstans | humans and primates | yes (potentially strain dependent) | biting midges (Culicoides) | mansonellosis | adults in serous body cavities, may also appear subcutaneously; mf in blood | mostly asymptomatic; occasionally Calabar swellings, itching, pruritus, joint pain, enlarged lymph glands, neurological symptoms | western, eastern, central Africa; equatorial Brazil to Caribbean | [13,14] |
| Mansonella streptocerca | humans and primates | not reported | biting midges (Culicoides) | mansonellosis | adults in subcutaneous tissues; mf in skin | mostly asymptomatic; occasionally dermatitis, pruritus, rash, papular skin, inguinal adenopathy, dizziness | western, eastern, central Africa | [13] |
| Litomosoides sigmodontis (aka. Litomosoides carinii in older literature) | cotton rats Sigmodon hispidus (experimental models: rats, Mastomys, mice, jirds) | yes | rat mites (Ornithonyssus bacoti) | cotton-rat filariasis | adults in pleural cavity (less commonly in peritoneal cavity); mf in peripheral blood | can cause wasting and affect survival; pathological changes in lungs, spleen and lymphatics; scattered myocarditis | likely southeastern United States, Mexico, and Central America; used as a model to study filarial infection | [15,16,17,18,19] |
| Dirofilaria immitis | companion animals (mainly dogs but also cats, ferrets) and wild animals (wolves, coyotes, foxes, pinnipeds, raccoons, etc.); can also infect humans with D. repens infecting humans to a greater extent than D. immitis | yes | mosquitoes | dirofilariasis/ dirofilariosis, aka. heartworm disease | heart and pulmonary arteries | in dogs: cough, exercise intolerance, fainting, coughing up blood, severe weight loss, congestive heart failure | most countries with temperate, semitropical or tropical climates | [20,21] |
| Dirofilaria repens | subcutaneous dirofilariasis/ dirofilariosis | adults in subcutaneous tissues; mf in peripheral bloodstream | mostly asymptomatic; occasionally pruritus, dermal swelling, subcutaneous nodules containing the parasite, and ocular conjunctivitis | Europe, Asia, Africa | [22] | |||
| Loa loab | humans (experimental models: primates (e.g., baboons), rodents) | no | deerflies, genus Chrysops | loiasis, aka. African eye worm | connective tissue | mostly asymptomatic, eye worm, Calabar swellings, itching, tiredness, muscle and joint pain, hives | West and Central Africa | [23] |
* in specified host; LF, lymphatic filariasis; mf, microfilariae.