Welcome to the indoor allergy season

John P. Lapotaire, CIEC

Central heating and double glazing keeps us warm in the winter months, but the house dust mite loves them too.

The cold weather’s arrived and the nights are drawing in: it’s that time of the year again to turn on the central heating and be glad of double glazing. However, allergy experts are warning that we are not alone in finding our homes a winter haven.

For the house dust mite the warm and slightly humid atmosphere of our centrally heated, hermetically sealed houses are a perfect place to survive and propagate – and they are a major cause of allergies at this time of year.

This is the start of the indoor allergy season. Allergies are very common, with estimates of one in three people having an allergy at some time in their lives. People have an allergic reaction when their immune system reacts to a harmless substance by making a specific antibody to fight it. This releases histamine and other chemicals which are the cause of inflammation and irritation.

What causes indoor allergies? House dust mites are the leading cause of indoor allergies. Most of the problems stem from the mite’s droppings which break up into extremely small particles – tiny enough to be inhaled deep into the lungs.

However, they are not the only cause of indoor allergies.

Everywhere in the house there will be microscopic mould allergens, unable to be seen by the naked eye. Mold favours warmth and dampness, so expect to find it in bathrooms, kitchens, fridge door seals, shower curtains and the corners of window frames. Mold may also be present in the moist soil of pot plants.

A pet – such as a dog or a cat – is also a source of allergens. These come from their dried saliva and skin flakes that they shed. Smaller domestic animals, such as guinea pigs and hamsters can distribute allergens from their urine-soaked bedding as they scurry around their cage.

So, what are the symptoms of indoor allergies? According to the Asthma, Allergy & Inflammation Research charity (AAIR), the principle culprit of indoor allergies – the house dust mite – can trigger allergic reactions such as asthma, eczema and rhinitis – a condition where the inside of the nose becomes inflamed, causing cold-like symptoms such as sneezing and a blocked or runny nose.

Other symptoms of indoor allergies are: Coughing, wheezing shortness of breathItching, watering and inflammation of the eyesHeadacheDisturbed sleepPoor concentration

Symptoms are often worse while in bed or first thing in the morning.

“Sneezing is the obvious symptom,” says Rosie Bradshaw from Guernsey describing her winter allergies. “It makes me very tired,” she tells us. She says house dust mites, fluff, animals, household cleaners and open fires have all triggered allergies.

Combating the indoor allergies The experts say there are ways to fight back against indoor allergies.

One of the first things to do is to reduce dampness. The AAIR charity recommends opening windows while cooking, washing and bathing. Also, avoid hanging clothes up round the house to dry: the evaporated moisture has to go somewhere.

“I try to open the windows as much as possible,” says Bradshaw, who would rather put on extra clothes than turn the heating up. “Fresh air is wonderful,” she adds and helps her avoid any problems with condensation in the house.

Its recommended that you encase mattresses, duvets and pillows with allergen-proof barrier covers and washing all other bedding once a week at 60 degrees or above – a temperature high enough to kill house mites.

It also recommended that you remove carpets and cartpeting whenever possible or vacuuming them regularly with a high-filtration HEPA vacuum cleaner.

“We have wooden floors in the bedroom because they’re easier to clean and you don’t get the dust that you get with a carpet,” says Bradshaw. “And we have cotton linen, which we wash very hot, and we have protectors on our mattresses and pillows,” she says.

Cats and dogs As for pet allergies, the experts at the AAIR charity say households who do not currently have a pet should think carefully before acquiring one, particularly if there is a family history of asthma or allergies. Asthma UK says people who have cats and dogs should bar them from the bedrooms and preferably living areas too. Dogs and cats should be washed regularly, groomed outdoors and their bedding should be laundered.

Bradshaw says that people should try to discover what causes their allergic reaction. However, she cautions that finding out – and then making any necessary changes – could be a lengthy process. “It’s trial and error. You have to do it over a period of time because all these changes are major changes affecting the whole family,” she says.

• John P. Lapotaire, CIEC• Certified Indoor Environmental Consultant• Microshield Environmental Services, LLC• www.Microshield-ES.com