The Protective Role of Helminths in Autoimmunity

For the past several decades, Western industrialized countries are facing a high rate of auto-inflammatory disorders, which are being expressed by a higher prevalence of autoimmune diseases and allergies. The lifestyle in industrialized countries had led to a decrease in infectious burden; however, a reverse correlation has been seen with the prevalence of autoimmune diseases. Limited exposure to microorganisms such as helminths and microbes during childhood eventually leads to an off-balanced immune system. This theory, known as the hygiene theory or the hygiene hypothesis, was first proposed by Strachan, who observed an inverse correlation between hay fever and the number of older siblings while following up more than 17,000 British children born in 1958.