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The dawn of allergies

In this article Andreas J. Bircher explains how major epidemics in human history led to a better knowledge on immunity and the discovery of allergies.
© University of Basel

Infections are known since antiquity. In the 19th century, the discovery of particular bacteria causing diseases led to a better understanding of immune processes and, in turn, to the development of vaccinations. By exact observations this ultimately resulted in the discovery and definition of a new phenomenon – the manifold allergic reactions and diseases.

‘Ring-a-round the rosies,
A pocket full of posies,
Ashes! Ashes!
We all fall down.’

Some scholars suggest that this well-known nursery rhyme might refer to the plague and describes the red swellings and purulent lesions (the ‘posies’). Others believe it is a reminiscence to smallpox, describing the central blisters later turning purulent (‘posies’), surrounded by a red aura (‘ring-a-round the rosies’), and often leading to death (‘ashes, we all fall down’).

For centuries in human history, infections were among the most common causes of death. Some infectious diseases – such as anthrax, rabies, gangrene, or tetanus – were continuously present menaces. Others typically spread from one individual to another and caused devastating local epidemics, often changing the course of history. Among the ones which caused several pandemics were the plague, syphilis, smallpox, cholera, tuberculosis. And in the last 120 years: from 1918-20 the Spanish flu, from 1957-58 the Asian flu, from 1968-69 the Hong Kong flu, and from the 1980s onwards AIDS. More recently in the 21st century smaller outbreaks of SARS, MERS, Ebola, swine flu, avian flu followed, and now most recently the pandemic of COVID-19 caused by the SARS Coronavirus-2 broke out. Below you find three historical examples of diseases causing millions of deaths.

This overview offers abridged historical information about some of these diseases.

In the 19th century, the investigation and identification of the manifestations and causes of infections lead to an increasing understanding of the complex mechanisms of the immune system. It allowed to develop vaccinations, ie preventing the diseases and saving millions of lives. Untoward reactions to vaccines, in turn, lead to the discovery of previously unknown phenomena – hypersensitivities, later called allergies. The investigation and description of such problems laid the basis for a new clinical discipline – Allergology.

Some people say that allergies, although not contagious, are one of the epidemics of the 21st century (D’Amato et al. 2015; Ober & Yao 2011). Do you think this assertion is accurate? Please leave a comment in the section below and share your reasoning.

Additionally, we would like to invite you to a rather playful approach that we have nicknamed ‘Catch an Allergy’: think of images that you associate with allergies – plants, animals, or food causing reaction etc. Take a photograph or make a scribble and share it on this Padlet with your explanation. Please make sure that you do not infringe any copyrights or personal rights with your contribution. We look forward to your arguments and creative output!


D’Amato, G. et al. (2015). Meteorological conditions, climate change, new emerging factors, and asthma and related allergic disorders: A statement of the World Allergy Organization. World Allergy Organization Journal, 8(25), 1-52. DOI: 10.1186/s40413-015-0073-0

Ober, C. & Yao, T. (2011). The genetics of asthma and allergic disease: a 21st century perspective. Immunological Reviews Special Issue – Allergic Responses, 242(1), 10-30. DOI: 10.1111/j.1600-065X.2011.01029.x

Platts-Mills, T. A. E. (2015). The Allergy Epidemics: 1870–2010. Journal of Allergy and Clinical Immunology, 136(1), 3-13.

© University of Basel
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Allergies: When the Immune System Backfires

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