D. insignis and D. lutrae are not transmissible to man, and therefore, are not of public health significance

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Gravid adult female D. insignis and D. lutrae are found in the subcutaneous space of the front and hind legs, thorax, abdomen, and groin. The worms are generally in the fascia in the tibial region of the hind leg. The anterior end of the viviparous female penetrates the dermis resulting in the formation of a blister. The blister soon ruptures and an ulcer forms. When the ulcerated area contacts water, the skin over the gravid female ruptures. First-stage larvae are liberated into the water and are ingested by suitable intermediate copepod hosts, the cyclops, Cyclops vernalis and C. bicuspidatus, and possibly other species. The infected cyclops may contain from 1 to 23 larvae, but usually has only 4 or 5 present. After larval ingestion, the copepods may become lethargic and may live only 50 days. The first-stage larvae develop to the infective third-stage larvae in a few weeks.

A paratenic host, such as frogs (leopard frog, Rana pipiens, and green frog, R. clamitans) or fish (rainbow trout, Salmo gairdneri, and white sucker, Catostomus commersoni) may serve as an accumulator of the D. insignis and possibly D. lutrae infective stage larvae by eating the infected cyclops. The accumulation of infective larvae maintains the high prevalence of the worm in the definitive hosts. The infective third-stage larvae probably remain viable in frogs for extended periods of time, so that large numbers of larvae can be ingested by eating a single frog.

The definitive hosts become infected by eating infected reservoir hosts or by drinking water containing parasitized cyclops. The infective larvae are released in the intestinal tract. The larvae penetrate the wall of the host's intestine and migrate through the body cavity to the connective tissues of the abdomen, thorax, and groin. In these preferred locations, the larvae mature, with the prepatent period usually being a year but possibly being as short as 77 days. Following maturity, the worms mate, and egg development in the female occurs.