Red blood cells and other tissues in the body become partially digested and tissue debris is carried to the kidneys, to be eliminated from the body. Too much debris can cause blockages in the kidneys, resulting in renal insufficiency or renal failure. Patients in this condition require medical intervention, even dialysis. The best way to prevent unpleasant encounters with social wasps is to avoid them. If you know where they are, try not to go near their nesting places.
Wasps can become very defensive when their nest is disturbed.
Be on the lookout for nests when outdoors. Scavenging wasps will not become a problem if there is no food around to attract them. When nuisance wasps are present in the outdoor environment, keep foods and drinks covered or inside and keep garbage in tightly sealed garbage cans. Once food is discovered by wasps, they will continue to hunt around that location long after the source has been removed. If wasps must be eliminated, it is easiest and safest to call for professional help.