No evidence for belief that nut allergens spread through aircraft ventilation systems, say experts

There isn’t any proof for the generally held perception that nut allergens will be unfold by way of plane air flow programs, say allergy and aviation drugs specialists in an proof overview printed within the Archives of Illness in Childhood.

Allergen residues on surfaces, reminiscent of tray tables, and seat-back video screens, pose the primary threat—a threat that’s probably heightened by the quick turnaround occasions deployed by many low-cost carriers, they counsel.

And allergic reactions to meals are round 10 to 100 occasions much less widespread throughout flights than they’re “on the bottom,” they level out, though this may very well be on account of passengers with meals allergic reactions taking extra precautions when flying, they acknowledge.

Round 2–3% of youngsters and 1–2% of adults within the UK have a meals allergy, say the authors. And comparable charges are noticed in medium to excessive earnings international locations. Meals allergy is the commonest reason for anaphylaxis, a doubtlessly life threatening allergic response.

In a bid to dispel a few of the misconceptions in regards to the perceived dangers posed to passengers with meals allergic reactions on business flights, the authors drew on the systematic overview of the printed proof courting again to 1980, commissioned by the UK’s Civil Aviation Authority (CAA) in 2023.

With the notable exceptions of vapors from fish/seafood and publicity to occupational wheat flour, allergic reactions to aerosolized meals are uncommon, and infrequently reproducible, say the authors.

Whereas peanut allergens will be detected at very low ranges within the air when shelling nuts, the mud settles shortly and might solely be detected in very shut proximity to the nuts, implying that little or no mud circulates within the air.

What’s extra, plane cabin air flow programs are designed to flow into air throughout the plane, slightly than alongside the cabin, so minimizing the potential for spreading passenger-generated contaminants by way of the cabin, clarify the authors.

Air is totally exchanged each three to 4 minutes throughout a flight. This compares with each 10 minutes for hospitals and lecture rooms. In trendy massive business plane, round half of the air consumption is recirculated air that has handed by way of particulate air filters which successfully take away mud, vapors, microbes, and seize aerosolized meals particles on the identical time. The opposite half comes from outdoors.

Meals proteins are sometimes “sticky,” and any unintentional publicity probably stems from floor contamination on seats, seat-back leisure programs, and tray tables. This may very well be transferred from the palms both to meals being eaten or on to the mouth and/or face.

Cleansing these surfaces firstly of a flight with sanitizing wipes will decrease this threat, and is “notably necessary, given the minimal cabin cleansing which regularly happens in between flights, particularly with low-cost carriers,” spotlight the authors.

Permitting food-allergic passengers to pre-board could also be useful on this respect, say the authors, who be aware that the US Division of Transportation already requires airways to permit passengers with nut allergic reactions to do that.

However bulletins requesting passengers to not devour nuts throughout the flight are unlikely to cut back the danger of in-flight reactions, and may present false reassurance, they add.

Whereas many passengers with meals allergic reactions want to convey their very own meals, the place an in-flight meal service is offered, most airways provide allergen-free choices, if requested upfront.

And passengers prone to meals anaphylaxis ought to carry adrenaline [epinephrine] auto-injectors, reminiscent of an EpiPen of their hand baggage, as these aren’t at all times included in onboard medical kits, nor are cabin crew at all times allowed to make use of them, advise the authors.

“There isn’t any proof that peanut or tree nut allergens are unfold by way of plane cabin air flow programs. Reasonably, the primary dangers are on account of both failure of dietary avoidance, or allergen residues on surfaces, which may then be transferred by way of contact—a scenario exacerbated by the very brief turnaround occasions with many low-cost carriers,” conclude the authors.

“Airways ought to have clear insurance policies referring to meals allergic reactions that are simply out there from their web sites or on request. These insurance policies needs to be utilized constantly by each floor employees and cabin crew, with a purpose to present reassurance to food-allergic passengers and their caregivers,” they add.