Why do gnats swarm around a open sore or cut?

Gnats are attracted to open sores or cuts due to the moisture and the presence of proteins and nutrients found in the blood and bodily fluids. These insects are drawn to the scent of decay and organic matter, which can be associated with wounds. Additionally, the warmth and humidity of the skin can create an inviting environment for them. Their swarming behavior can also be a response to the pheromones released from the site of injury.