Wisdom From Flyers With Nut Allergies

Credit Tony Cenicola/The New York Times

When Roxanne Palin of Manhattan travels by plane with her family, some of whom are allergic to tree nuts or peanuts, she has a standing battle plan. She books flights in advance so that the three with allergies can sit together, and makes sure they bring their own food and beverages. She swabs their seats and table trays with alcohol pads or baby wipes. She packs eight doses of self-injectable epinephrine, including back-ups, in case any of them has an allergic reaction.

Once onboard, she begins her polite campaign of explanation and entreaty. To flight personnel. To nearby passengers. “If I see them being offered nuts,” said Mrs. Palin, “I say, ‘Would you mind? I have children with life-threatening food allergies and it makes them nervous to be on a plane where there are nuts. Would it be possible for you to elect to eat something else?’” Many people comply without a murmur. “And some people say, ‘O.K.’ and they eat the nuts anyway.’ ”

In-flight allergy reactions to tree nuts and peanuts have been reported by only small numbers of passengers, and scientists are uncertain whether dust from the nuts poses serious airborne risks to travelers with allergies. But Mrs. Palin is far from alone in taking a pro-active stance, as a new study of 3,273 air travelers with these types of allergies affirms.

“Even though it’s a rare event, we wanted to determine what would influence that rare event from happening,” said Dr. Matthew Greenhawt, a clinician and researcher at the University of Michigan Food Allergy Center, and the lead author of the study, which was published in the latest issue of The Journal of Allergy and Clinical Immunology: In Practice.

He and his colleagues asked peanut and tree nut allergy sufferers from 11 countries, only some of whom had in-flight reactions, what precautions they routinely took when they flew. The most common strategies cited included requesting a buffer zone around the allergy-affected passengers, in which peanuts or tree nuts would not be served; requesting a general announcement that passengers not eat peanut or tree nut-containing food; and ordering a peanut or tree nut-free meal. Other common safety measures included wiping their tray tables, bringing their own food and avoiding use of airline pillows and blankets.

In addition, travelers reported bringing their own epinephrine (even though American carriers must include them in their emergency medical kits); asking to preboard the plane (presumably to clean); wiping seat backs, seat belts and other surfaces like bathroom door handles; and requesting to sit in a particular seat or area that they believed would mitigate their risk.

Perhaps reflecting cultural differences, Canadian and European travelers were far more likely than Americans to request an announcement that fellow passengers not eat food with nuts. But Americans were more likely than travelers from Europe, Asia and Canada to wipe their tray tables, decline airline pillows or blankets, and request preboarding.

“If you’re as careful as you can be, the chances of having a reaction are less,” said Dr. Julie Wang, an assistant professor of pediatrics, allergy and immunology at the Icahn School of Medicine at Mount Sinai, in New York, who was not involved in the study. The study, she noted, was observational; it did not state that taking such precautions directly prevented allergic reactions.

Just over 1 in 10 passengers who responded to the questionnaire reported having had an allergic reaction on an airplane within the previous five years. Some who had reactions reported taking precautions, while others who made no such efforts reported being fine.

Strikingly, and consistent with other studies, when a reaction occurred, epinephrine was sparsely used. “Perhaps they didn’t perceive their reaction to be severe enough to merit epinephrine,” said Dr. Greenhawt. “But past evidence has shown that many of these reactions are quite severe and the EpiPens should have been used.” Dr. Greenhawt speculated that travelers might not have understood the gravity of their reaction or wanted to avoid drawing attention to themselves.

Federal legislation prevents regulation of in-flight nut restrictions until a scientific study shows that the dust circulates in the air and also triggers reactions in those with the allergies.

But the dust may have other ways of spreading besides being airborne: Mrs. Palin’s husband once had an in-flight reaction, the family believes, because he touched a bathroom door handle with peanut residue from another passenger.

“The looming issue is: should peanuts be taken off airplanes?” said Dr. Greenhawt. Absent hard evidence of airborne transmission, he added, “There are protective measures that passengers can consider taking themselves that might make their flying experience safer.”