You conjure a field of mosquitos in a 30 foot radius area within range. The insects are infected with the disease used in the casting of the spell, and will spread it to whomever they bite.
The swarm is sparse and hard to immediately notice. A creature can make a Wisdom (Perception) check against your spell save DC to notice that there are more insects in the area than normal. A creature will instantly notice the swarm when it is bitten.
A creature that enters the area for the first time or starts its turn in the area is bitten, and must make a Constitution saving throw. On a failed save, it becomes infected with the disease you used in the casting of this spell. On a successful save, it cannot be infected by the insects in the area for the duration.
* - (25 gp worth of herbal reagents and a vial containing a sample of a contagious disease, which the spell consumes)
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