Flying with peanut allergy or any nut allergy has been a source of fear for many patients. Food allergies affect up to 5-8% of children in the United States and may be increasing in prevalence. The most common causes of significant allergic reactions are milk, egg, wheat, soy, peanut, tree nuts, fish, shellfish and seeds. Although there are treatment options for food allergies such as immunotherapy, they are not currently FDA approved for general use. The current management relies on avoidance of the allergen.
Because the most common food allergens are ubiquitous, complete avoidance can be difficult and unintentional ingestions are common. Fatalities caused by food allergy are rare but accidental exposures can lead to potentially severe reactions.
Appropriate avoidance includes correctly reading ingredient labels, understanding the risks of casual contact with an allergen and use of appropriate practices to prevent cross contact.
A big question commonly asked amongst allergists is the safety of flying with peanut allergy. The New York Times last year reported a story of family removed from a flight because the children had nut allergy and the pilot did not want to be liable. The statement released by the airline was “The pilot determined it would be best for the family not to travel based on the severity of the allergy and the need to divert the airline if anyone were eating nuts.”
A recent study sought to identify potential risk-mitagating factors among individual reporting inflight peanut or tree nut reactions on international flights. Behaviors that were found mitigating were:
- making any requests of the airline
- requesting a buffer zone
- requesting an announcement that passengers no eat goods that contain peanuts or tree nuts
- requesting a peanut or tree nut free meal
- wiping their tray table
- bringing their own food from home
- avoiding an airline provided pillow and blanket
- having an epinephrine autoinjector readily available (2 of them)
Overall, inflight medical emergencies are rare with allergic reactions contributing to a small portion of events and most peanut allergic passengers fly without event. There is no evidence to support that commercial air travel is dangerous or should be contraindicated for the peanut allergic patient. In addition, they are not at an elevated risk relative to any other situation. However, many patients and advocates do not advocate this view and consider air travel risky. Studies on inhalational and contact exposures to allergens do not support the notion of systemic reactions with casual contact.
In terms of peanut inhalation, Perry et al simulated real-life situations in which one may be exposed to peanut protein, such as a school cafeteria, attending a sporting event and commercial airline travel by using 19 people wearing a personal air monitor with to measure of Ara h 1 (a peanut component). Ara h 1 was undetectable in all simulated situations. Another study by Brough et al evaluated the presence of peanut protein in homes with household peanut consumption. The airborne levels were lower than the limit possible for quantification except for immediately after a peanut was shelled. Roberts et all identified 5 patients who reacted to aerosolized forms of food while being cooked, the symptoms were similar to inhalation of aeroallergens. The evidence demonstrates that inhalation exposures to peanut products are unlikely to trigger allergic reactions.
The decision to travel on a commercial airline that serves a culprit allergen is individual, but the available evidence demonstrates that the presence of an allergen is of low risk, likely not to cause any problem as long as the allergen is not directly ingested. Tree nut or peanut allergy should not serve as a contraindication for travel in most circumstances, given a low likelihood of an event occurring and multiple risk-reducing behaviors that passengers can implement.
Perry TT, Conover-Walker MK, Pomes A, Chapman MD, Wood RA. Distribution of peanut allergy in the environment. Journal Allergy Clinical Immunology. 2004; 113: 973-976
Brough HA, Makinson K Peanagos M, et al. Distribution of peanut protein in the home environment. J Allergy Clin Immunology. 2013; 132: 623-629
Roberts G, Golder N, Lack G. Bronchial challenges with aerosolized food in asthmatic, food allergic children. Allergy. 2002;57: 713-717.