Peanut allergy is one of the most common food allergies found worldwide. In the Western world, the prevalence can be as high as 1 in 200 individuals in some populations. In the United Kingdom, peanut allergy is present in between 0.4 and 0.6% of the whole population.
Studies show that peanut allergy forms around 28% of all food allergies in children and develops before the child reaches their first birthday in about half of cases. The allergy rarely develops after 15 years of age (in only 7% of cases).
Peanut allergy is one of the largest known causes of food allergy induced anaphylaxis, the most severe form of allergic reaction. Anaphylaxis is a life threatening condition that needs immediate treatment. In a 2001 report, it was found that of 32 anaphylaxis cases recorded in a US national registry, the peanut allergen caused 14 reactions and was a possible trigger of a further 6.
While peanut allergy looks like a serious problem in the West, it is much less common in other regions of the world, especially China. In Beijing for example, food allergies make up only 3.4 to 5.0% of all allergies and are triggered by fish, shrimp, seaweed, and crab, but not the peanut. However, the Chinese-American population in the USA has a similar prevalence of peanut allergy as other US populations.
In Australia, severe peanut reaction has a prevalence of only 0.25% and fatalities in those aged under five years are rare. A study of 456 Tasmanian children, for example, showed that no child reacted to peanut protein.