You hear a rattling cough and the shuffling of feet, as someone walks through the ruins of a destroyed hab-block. Said someone seems to mumble to himself, probably something about Nurgle's glory, as indeed this slow, shambling step can only be that of an infected cultist.

turning to see the person that produces these noises, you see indeed that the one to make this noise is a cultist of the cult of admonition, as he walks through the ruins, seemingly on guard.