The smell of spring blossoms, or indeed, hay, might get your nose and eyes running and itching but neither is likely to cause hay fever. Pollen particles are usually the culprit behind hay fever, also known as seasonal allergic rhinitis, which packs a sneezy punch to many of us during spring and summer.
New Zealand is in the top three countries in the world to be affected by allergies. About 30 per cent of us will experience hay fever, according to clinical immunologist/allergist Dr Andrew Baker. He says it’s pollen from grasses, birch trees and the English plantain plant, a broadleaf weed that’s often mixed in with grass, that get up people’s noses during spring and summer.
Allergens that cause allergic rhinitis, or allergic rhinoconjunctivitis if the eyes are affected, are airborne. People can assume food allergens cause hay fever but that’s not the case, Dr Baker says. The allergen has to land in your eyes, up your nose or be inhaled through your mouth to start creating allergy havoc.
If you’re allergic to grass, for example, the reaction starts with a protein of the grass allergen landing in the lining of your nose or eyes. It will then bind to your IgE (immunoglobulin) antibodies to grass, and then to a mast cell. The mast cell then becomes activated and releases mediators, such as histamine. This is when you can start sneezing and feel dreadful with a runny nose and itching in the eyes and throat.
For many, a bout of hay fever may simply require reaching for some tissues or heading to a pharmacy for antihistamines and perhaps a nasal spray. If an ad-hoc, over-the-counter approach doesn’t provide lasting relief, a visit to a GP or an allergy specialist for a longer-term treatment plan is probably necessary.
“Some people will only sneeze a few days out of the year, but others are affected so badly that they can’t leave their house during spring and summer,” Baker says.
Treatments for chronic hay fever include daily doses of corticosteroid nasal sprays and antihistamines. Allergy testing, where a tiny dose of an allergen is pricked into the skin to test for an allergic reaction, can be useful to identify allergens but is not entirely accurate, Baker says.
“Some people can have positive skin tests but don’t actually have an allergy.”
Severe hay fever sufferers can also undergo immunotherapy. Essentially, it’s desensitisation therapy where the immune system is trained to become less sensitive to allergens over time. Tiny doses of the allergen are usually administered in monthly injections across three years, but tablets and sprays can also be used. Results vary but Baker says most people who try immunotherapy get some sort of relief.
Intranasal phototherapy, where a UV light-emitting device is inserted into the nose to reduce inflammation, is a therapy sometimes used overseas but is not widely adopted in New Zealand.
Avoiding the allergen in the first place might be obvious but is not straightforward, even when you know what’s setting your hay fever off. Grass pollen, easily a top allergy offender during spring and summer, has a light structure and can be transported by wind over hundreds of kilometres.
“You can be in a concrete jungle and not see a blade of grass but still be affected by grass pollen that may have blown in from a farm 100km away,” Baker says.
Hay fever-type symptoms can also be caused by irritants such as the pollen from pine and privet, smoky air or fragrances. This is not true allergy but can further irritate allergy sufferers, who may be confused about what they’re reacting to.
“Basically their nose and eyes are already inflamed and irritated by the allergy and being further aggravated by irritants. True allergy usually causes itching, and a watery and runny nose and eyes.”
Hay fever can also look like a cold, but the trick is to test the symptoms by trying an antihistamine. If the symptoms get better, it could be an allergy.
Nasal blockage is another condition that can be mistaken for hay fever, Baker says. When they’re sneezy, people might grab a short-term nasal spray from the pharmacy that seems to alleviate symptoms but can end up exacerbating the problem. These sprays, which should only be taken for two or three days at the most, can cause rhinitis medicamentosa, otherwise known as rebound blockage.
“People can think these sprays are so helpful because the moment they spray them up their nose, they feel way better and they think it’s the only thing that’s working, but it’s actually clearing the nasal blockage that it’s causing in the first place.”
Not all hay fever symptoms run through spring and summer. Dust mites, for example, are common airborne allergens and can affect people year-round. They thrive in New Zealand’s temperate, humid climate and most of our homes will host them to some degree. The mites nest and breed in soft furnishings, which means carpet, furniture and bedding can be riddled with them. Though eradicating dust mites might be an impossible task, paying close attention to bedding can help, Baker says.
“People can be lying on pillows that are five years old that will have a huge amount of dust mites and they’re breathing it in all night.”
Washing bed linen, pillows, blankets and duvet inners is generally ineffective, as is airing these items outside in the sun. “Washing the pillow covers usually won’t help because the dust mite is on the inside fluffy stuff. You need specialised covers impermeable to dust mite, or else you need to change the pillow or duvet every two years.
