Alive but probably not healthy. Behind the damselfly's head and between its large compound eyes is a small dark brown, circular structure, which I understand is the anterior thoracic spiracle. This provides oxygen to the damselfly’s wing muscles and brain and has a flap-type valve which opens and closes as necessary. This feature is usually hidden from view behind the head/eye structure, but is visible in the first image. A close look at the spiracle shows its valve to be closed and a grub like parasite stretched across it, attached to the damselfly.