Neuroshima Hex 3.0 Death Breath

From the publisher:

The Death Breath is a terrifying virus which began spreading forth from the eastern enclaves of the Moloch. It infects every living thing, changing them into brainless, bloodthirsty beasts. Victims of these attacks become infected with the virus, and so it spreads.

So far, the most effective way of dealing with the infected are strong ammunition, grenades, and a sharp axe.