Why is there an Allergy Epidemic? Twitter summary from 2014 #ACAAI meeting

This is a summary of the debate Hygiene Hypothesis/Microbiome vs Climate Change.

According to Dr Portnoy, CO2 on Mauna Loa went from 320 ppm to 400 ppm from 1960 to 2010, sunlight goes in, heats up the Earth and can't get out. Health effects of CO2: rodent and insect borne diseases, changes in seafood borne diseases, contamination of drinking H2O, etc. There's an association with CO2 and allergy epidemic. Increasing levels of CO2 production lead to increase of ragweed pollen production and potency. This also explains increased ragweed allergy in cities (where there is more CO2) than in rural areas. However, even he admits that association does not prove causation.

Dr Ownby is arguing for hygiene hypothesis and microbiome. His declaration is that he is happy that he was raised on a farm.

It should really be the Microbiota Hypothesis rather than the Hygiene Hypothesis.

Most people moved off farms in last century and access to clean water was not really universal until the 1970s, the start of epidemic.

90% of antibiotics given to livestock are for non-infectious reasons (ie to make them fatter). TV dinners started in 60s/70s. We also don't buy fresh foods that may have soil contamination but prepackaged sterile foods.

Allergic (atopic) march (click here to enlarge the image). Allergic (Atopic) March refers to the natural history or typical progression of allergic diseases that often begin early in life. These include atopic dermatitis (eczema), food allergy, allergic rhinitis (hay fever) and asthma.

There is an allergy gap between Russian and Finnish kids, with differences in cat exposure and ground H20 contamination as proof - Allergy 66:886. Here's the link to the Allergy Gap paper in Allergy http://t.co/gv1rJmdQNr

Dr Stan Szefler discussed acetaminophen as a suspected reason for allergy epidemic. “When we experienced Reye's Syndrome in the 1970s, we changed from ASA to acetaminophen, so the timing is right.”

Two hypothesis for acetaminophen making asthma worse 1) in utero exposure, 2) childhood exposure - #2 is stronger. You should be familiar with Beasley article - AJRCCM 2011 http://t.co/d53sOX5ZgZ

Dr Peden discussed smoking, air pollution and indoor triggers as root cause for allergy epidemic. Ozone and environmental smoke exposure enhance allergic airways disease. Ambient air pollution impairs T regs in humans - JACI 126:845. Exposure to tobacco promotes IgE, DNA methylation resulting in Th2 and genetic factors increase risk of response to irritants.

Dr Portnoy still claims it's still climate change at the root - driving people indoors and thus winning Dr Peden's arguments indirectly. Dr Peden continued to argue convincingly that tobacco smoke and pollution contributes to microbiome, climate change and all others.

Dr Tom Platts-Mills said there were multiple allergy epidemics, not just one. Hay fever started around 1905, peanut food allergy around 1995 and pediatric asthma epidemic 1970s. Dr Platts-Mills: Allergy Epidemic actually followed 3 phases - SAR 1st, then pediatric asthma, and finally food allergy, decades apart.

What happened in 1954, the origins of the pediatric asthma epidemic?... Introduction of TV. Most children are not exposed to pollen these days. Inactivity due to indoor living leads to asthmatic changes.

This is a Twitter summary from 2014 #ACAAI meeting. The post is a part of series. See the rest here: http://allergynotes.blogspot.com/search/label/ACAAI

The Twitter summary was made possible by @DrAnneEllis and @MatthewBowdish

Several allergists did a great job posting updates from the 2014 meeting of the #ACAAI. I used the website “All My Tweets” to review the tweets. For comparison, here are the tweets from previous #ACAAI meetings (scroll down the page for the past years): http://allergynotes.blogspot.com/search/label/ACAAI

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