The only associated symptom in the Peace Corps study was nausea.Researchers believe that geo-mapping of appropriate habitat and human settlement patterns may, with the use of predictor variables such as forest, land cover, rainfall, temperature, and soil type, allow for estimation of Loa loa transmission in the absence of point-of-care diagnostic tests. In addition to geo-mapping and chemoprophylaxis, the same preventative strategies used for malaria should be undertaken to avoid contraction of loiasis. Specifically, DEET-containing insect repellent, permethrin-soaked clothing, and thick, long-sleeved and long-legged clothing ought to be worn to decrease susceptibility to the bite of the mango or deer fly vector. Because the vector is day-biting, mosquito (bed) nets do not increase protection against loiasis.Vector elimination strategies are an interesting consideration. It has been shown that the Chrysops vector has a limited flying range, but vector elimination efforts are not common, likely because the insects bite outdoors and have a diverse, if not long, range, living in the forest and biting in the open, as mentioned in the vector section. No vaccine has been developed for loiasis and there is little report on this possibility. Treatment
Treatment of loiasis involves chemotherapy or, in some cases, surgical removal of adult worms followed by systemic treatment. The current drug of choice for therapy is diethylcarbamazine (DEC), though ivermectin use while not curative (i.e., it will not kill the adult worms) can substantially reduce the microfilarial load. The recommended dosage of DEC is 8–10 mg/kg/d taken three times daily for 21 days per CDC.
Reservoir
Humans are the primary reservoir for Loa loa. Other minor potential reservoirs have been indicated in various fly-biting habit studies, such as hippopotamus, wild ruminants (e.g. buffalo), rodents and lizards. A simian type of loiasis exists in monkeys and apes but it is transmitted by Chrysops langi. There is no crossover between the human and simian types of the disease. A related fly, Chrysops langi, has been isolated as a vector of simian loiasis, but this variant hunts within the forest and has not as yet been associated with human infection. Vector
Loa loa is transmitted by several species of tabanid flies (Order: Diptera; Family: Tabanidae). Although horseflies of the genus Tabanus are often mentioned as vectors, the two most prominent vectors are from the tabanid genus Chrysops—C. silacea and C. dimidiata. These species exist only in Africa and are popularly known as deer flies and mango, or mangrove, flies.Chrysops spp. are small (5–20 mm long) with a large head and downward-pointing mouthparts. Their wings are clear or speckled brown. They are hematophagous and typically live in forested and muddy habitats like swamps, streams and reservoirs, and in rotting vegetation. Female mango and deer flies require a blood meal for production of a second batch of eggs. This batch is deposited near water, where the eggs hatch in 5–7 days. The larvae mature in water or soil, where they feed on organic material such as decaying animal and vegetable products. Fly larvae are 1–6 cm long and take 1–3 years to mature from egg to adult.