There is a new paper today “The Hygiene Hypothesis in the Age of the Microbiome“. Fortunately there is a strong paywall…
An impressive illustration of the hygiene hypothesis was found in the consistent farm effect on asthma and allergies, which has partly been attributed to immunomodulatory properties of endotoxin as emitted by livestock.
which is not aware of “Time to abandon the hygiene hypothesis: new perspectives on allergic disease, the human microbiome, infectious disease prevention and the role of targeted hygiene”
Although evidence supports the concept of immune regulation driven by microbe–host interactions, the term ‘hygiene hypothesis’ is a misleading misnomer.
see also “News Feature: Cleaning up the hygiene hypothesis”
Still, the catchy hygiene hypothesis continues to be widely embraced by the public, the media, and even scientists: Uses of the term in the scientific literature rose threefold over the past 10 years compared with the decade prior, according to a search on Thomson Reuters Web of Science. “In science, when something has been propagated for so long, it can be hard to change,” says Marsha Wills-Karp, chair of environmental health and engineering at Johns Hopkins Bloomberg School of Public Health.