Which stage of chiggers is known to be the parasitic stage that causes skin irritation?

The larvae stage of chiggers is known to be the parasitic stage that causes skin irritation. During this stage, chigger larvae seek a host to feed on, typically attaching themselves to the skin of animals or humans. They inject digestive enzymes into the skin, which breaks down skin cells, allowing them to feed on the resultant fluid. This feeding process is what leads to the intense itching and irritation often associated with chigger bites.

The other life stages—eggs, nymphs, and adults—do not contribute to skin irritation in the same manner as the larvae. While adult chiggers are present in the population, they are not parasitic and primarily feed on plant material. The egg stage is non-parasitic as well, with no interaction with hosts, and nymphs feed on similar materials to adults. Thus, the larvae stage is uniquely responsible for the skin irritation that people experience during chigger infestations.