Allergy season 2021: Climate change exacerbates your allergies

The warm, inviting spring air along with vaccinations for Covid-19 encourage people to gather outside. But for allergy sufferers, the air is packing a massive wall disc that could scare them indoors.

From Maine to Alabama, clouds of allergens run like pollen across cities, leaving millions of people with watery eyes, headaches and rashes. 2021 is becoming a cruel year for allergies again. Just like 2020, 2019 and 2018 …

The trend is real: allergy risk is getting worse over time. The length and intensity of pollen times are increasing, mainly due to climate change. And as the planet continues to warm, more misery is in the offing.

It is estimated that up to 50 million Americans have allergies, and as pollen counts increase, more people can become allergic.

“I think what will happen is that more people will become sensitive and then they will present themselves earlier because of the higher pollen count, especially with tree pollen,” said Sunil Perera, an allergist in Roseville, California, near Sacramento.

It will again become a greater burden on health and the economy, as even people with mild symptoms struggle to stay active and productive. The cost of treating nose allergies is already $ 3.4 billion a year in the US. Asthma attacks caused by pollen lead to 20,000 emergency visits a year in the US.

One complication this year, like last time, is the Covid-19 pandemic. Many people wonder if their suffering is caused by the virus or pollen. There are some overlapping symptoms between Covid-19 and allergies, such as a runny nose and a loss of smell, but allergies also show some obvious signs, such as itchy eyes and sneezing, according to the American Academy of Allergy, Asthma and Immunology. The more unique symptoms of Covid-19 are fever, cough and shortness of breath.

American Academy of Allergy, Asthma and Immunology

However, many people with Covid-19 have no symptoms at all. And there is no reason why someone could not have Covid-19 and allergies at the same time.

In fact, doctors warn that severe allergies can make people more vulnerable to respiratory infections. ‘When allergic inflammation occurs in the airways, [infections] is easier, ”Perera said. ‘We see simultaneous allergies and infections when [patients] come see us. ”

Face masks can provide allergies with some relief even when their eyes are exposed. But as the planet continues to warm up, allergy sufferers will find it harder to take refuge. Pollen grains range in size from 200 microns to 10 microns, with smaller grains that can penetrate deeper into the lungs. Small pollen grains can even seep indoors. And researchers are finding out how much our own insults are to blame for the environment.

How climate change exacerbates allergies

Allergies are the result of the immune system reacting to something that is otherwise benign. This can lead to irritating but mild symptoms such as hives or itchy eyes. But it can also cause life-threatening complications, such as anaphylaxis, where blood pressure drops and airways begin to swell.

Pollen is one of the most common allergens. It is produced as part of the reproductive cycle of plants. The timing of pollen production varies depending on the plant species, with trees peaking in spring, grass during summer and ragweed in autumn.

Johns Hopkins University, Division of Allergy and Clinical Immunology

There are mainly two ways in which humans can alter pollen production. One mechanism is that humans increase the concentration of carbon dioxide in the atmosphere by burning fossil fuels. Atmospheric carbon dioxide concentrations rose from 280 parts per million in the 1800s to 420 ppm.

“As CO2 rises, plants tend to get a little bigger,” said William Anderegg, an assistant professor of biology at the University of Utah. “They tend to have more flowers than a fraction of their mass, and individual flowers have more pollen.”

Plants that produce more pollen tend to produce more seeds. It also means more pollen-spitting plants in the next season.

The other mechanism is the warming caused by carbon dioxide. As it traps heat, higher concentrations of carbon dioxide in the atmosphere cause the planet to warm up. This leads to warmer winters and earlier springs, giving plants an advantage over pollen production. “As spring rises, all of these life cycle events, including pollen times, tend to shift earlier,” Anderegg said.

The combination of these two factors leads to more pollen production and over a longer period of time.

Mankind’s fingerprints are becoming more visible in the air with pollen

Attribution is the growing field of climate science that not only wants to find out how the climate is changing, but also the extent to which human activity is specifically to blame – and how much change would otherwise have taken place without human intervention. Scientists use observations and models to find out how phenomena, ranging from extreme floods to wildfires, would be different if humans did not spew gigatons of carbon dioxide into the atmosphere.

“Think of it as looking at a baseball player before and after they started using steroids,” said Lewis Ziska, an associate professor at the Mailman School of Public Health at Columbia University.

Researchers have now begun to attribute changes in allergens to human activity. In a study conducted in February in the Proceedings of the National Academy of Sciences of the United States of America, Ziska, Anderegg and their colleagues calculated that the human impact on the climate is about half of the increase in pollen times in North America. Climate change by humans also causes 8 percent of the observed increase in pollen concentrations.

“There is a very clear climate signal that it appears that we can be directly associated with these changes in pollen, both in terms of tax – how much pollen – but also in terms of the entire exposure time,” Ziska said.

Karl-Josef Hildenbrand / Picture Alliance via Getty Images

These effects are already visible, and as mankind continues to burn fossil fuels, these effects are poised to grow. Some estimates show that by 2040, the number of pollen in all parts of the country will double in some parts of the country, depending on the path the world follows on greenhouse gas emissions.

The northern latitudes are likely to sneeze the most, as they are the fastest warming parts of the planet. And pollen is not the only allergen that is of concern. As permafrost melts in places like Alaska, moisture flows into homes, creating an inviting habitat for mold. That form can then produce spores that cause allergies. Stinging insects are another concern in the far north. Warmer winters mean that more insects survive until spring, which increases their numbers. People who may not have realized that they are allergic to sting can eventually find out the hard way that they are vulnerable.

Jeffrey Demain, director of the Allergy, Asthma and Immunology Center of Alaska, told Vox in 2018 that he noticed that the northernmost part of Alaska had a 626 percent increase in insect bites and stings between 2004 and 2006, compared to the period between 1999 and 2001.

What emerges from the haze is that the health burden of all kinds of allergies is ready to grow, and that there will be little relief for allergy sufferers on the horizon. But it also highlights how the impact on climate change is already here, and it’s going to get worse. “It emphasizes the urgency of reducing greenhouse gas emissions and tackling climate change as quickly as possible,” Anderegg said.