Although spring most readily comes to mind when we think of allergies, many of the same allergic triggers that can make us miserable in the spring persist into summer. Add heat, humidity, and air pollution into the mix, and you have the recipe for summer allergy misery.
What causes summer allergies?
Just as in spring, the biggest summer allergy trigger is pollen - tiny grains released into the air by male trees, grasses, and weeds for the purpose of fertilising other plants. When these pollen cells get into the nose and eyes of susceptible people, they send the immune system into overdrive.
The immune system, mistakenly seeing the pollen as foreign invaders, releases antibodies - substances that normally identify and go after bacteria, viruses, and other illness-causing organisms. The antibodies attack the allergens, which leads to the release of chemicals such as histamine into the blood. These chemicals trigger the runny nose, itchy eyes, and other allergy symptoms.
Pollen can travel for miles, spreading a path of misery for allergy sufferers along the way. The higher the pollen count, the greater the misery. The pollen count measures the amount of allergens in the air in grains per cubic metre. You can find out the daily pollen count in your area from the TV, radio, internet or newspaper weather forecasts.
Trees generally finish pollinating by late spring, leaving grasses and weeds as the biggest contributors to summer allergies.
Here are some of the worst summer allergy offenders:
- Weeds like plantains, mugwort, nettles and docks produce bothersome pollen
- Wind-pollinated flowers such as the daisy family are another common source of problems
- Spores are produced by fungi such as mushrooms, and moulds like those in compost heaps
Some people's hayfever symptoms are triggered by just one or two of the above. Others are affected by more. Different pollens and spores are released throughout the year. To identify which ones you are allergic to, make a note of when your symptoms occur.
As if all of these airborne allergens aren’t bad enough, add summer air pollution to the mix. One of the most common pollutants is ozone, which is created in the atmosphere by a combination of sunlight, nitrogen oxide, and hydrocarbons from burning fuel. The stronger sunlight and calmer winds during the summer months can create clouds of ozone around some cities. Studies have found that ozone and other air pollutants worsen symptoms of allergies and asthma.
Another airborne allergen is of the flying, stinging variety. Bees, wasps, hornets, and other insects can cause allergic reactions in some people when they sting. Most stings are painful but harmless, and only affect the area around the sting. However, some people can have an immediate and more widespread allergic reaction to being stung, such as an anaphylactic shock, which can be fatal.
Although most summer allergens are found outdoors, culprits exist indoors as well. Moulds flourish in damp areas of homes such as bathrooms. Their spores get into the air and can cause problems for allergy sufferers both in the summer, and throughout the year.
House dust mites - microscopic, spider-like insects - are another common indoor allergen. Because they thrive in warm, humid temperatures, house dust mite populations peak during the summer months. They nest in beds, fabric, and carpets. Their residue can get into the air, and into your nose, triggering sneezes, wheezes, and runny noses.