My father donated blood some years ago, and the following morning, had a stiff elbow, that became really painful during the day.
Following day his elbow was red and badly swollen. Went to the quack, who freaked and sent him to casualty.
By the time he got to casualty, there were read and grey lines running up and down his arm a few inches, radiating from the red centre of his inside elbow.
They had to feed an antibiotic drip directly into the elbow (apparently hurt like nothing else), and systemic antibiotics as well.
7 days in hospital and no work for 2 weeks, hurt him badly as a self employed contractor.
Had Oz' foremost infection specialist treating him, who advised him that the only way he could have got an infection where he got it was for it to have been put there.
He approached the Red Cross re compensation. They responded with "sue us, you'll go broke before we do".