A study carried out in fiscal 2022 showed 6.3 percent of school children in Japan suffer from food allergies, an increase of 1.8 percentage points in around nine years, with the rate of severe allergic reactions, or anaphylaxis, also on the rise.

The latest survey by the Japan Society of School Health showed public elementary, junior high and high schools were aware of 526,705 children who had some form of food allergy, up from 4.5 percent in the previous study in fiscal 2013. Only 2.4 percent reported allergies in fiscal 2004.

A child eats a school meal in an elementary school in Tokyo on Dec. 6, 2022. (Kyodo)

Medical experts said the rising trend may be attributable to the more widespread prevalence of hay fever, as people who are affected tend to develop fruit allergies.

Allergy sufferers who had an episode of anaphylactic shock made up 0.6 percent in fiscal 2022, up from the previous 0.48 percent.

The most commonly reported food allergies in a multiple choice question were chicken eggs at 25.8 percent, followed by fruit at 25.0 percent and shellfish at 14.9 percent.

The study also showed 12.4 percent and 11.2 percent were allergic to nuts and peanuts, respectively.

The organization found that although 64.1 percent of schools in fiscal 2021 held allergy courses for teachers, just 26.8 percent simulated an emergency response to a potentially life-threatening case of anaphylaxis.

The swift use of an EpiPen, or an epinephrine auto-injector, is considered effective in the event of anaphylactic shock, and the society recommends schools train staff in how to use the device.

The study was conducted between October and December last year, with some 25,000 schools with a total of 8.3 million students giving valid responses.