Alternate Host
An alternate host is one of two (or more) hosts that a parasite requires to complete its life cycle. The parasite alternates between hosts to reach different developmental stages.
A common example is schistosomes, which alternate between snails (intermediate host) and humans (definitive host). Each host supports specific developmental steps that cannot occur in the other.
Why it matters: Understanding alternate hosts helps identify intervention points (e.g., snail control, sanitation, reducing water exposure).
