Some cases may "have gone unexplained and unreported," the researchers warned.
"We must analyse when this happens and how often it happens," Jacobs said. "We must create awareness that this phenomenon can take place."
Dr Dan Waxman, president of America's Blood Centres and chief medical officer at the Indiana Blood Centre, agreed that in the United States as well, there is a need for a national system to record how often these types of reactions occur.
He suspects that a peanut allergy-related reaction is extremely rare. What may be more of a worry, and what blood banks are addressing, he said, is the case of a patient who is allergic to penicillin, for example, getting a transfusion from someone who was taking the drug.
"We're really good about donor questionnaires about medication these days, or if someone's taking an antibiotic," Waxman, who was not involved in the new report, said.
"We ask a certain amount of health history (from donors), but in terms of what people might have eaten, we really don't ask." (Reuters Health/ May 2011)