https://news.ca.msn.com/top-stories/peanut-tainted-blood-triggers-allergic-reaction?wa=wsignin1.0
In 2007, for instance, an 80-year-old woman who'd recently received
blood developed an anaphylactic reaction within minutes of eating peanut
butter, according to a report in the journal Current Allergy and Asthma
Reports. She?d never been allergic before, but two days earlier she?d
been transfused with two units of blood from a 19-year-old donor who
turned out to have a severe peanut allergy.