Environmental Control Procedures for Common Allergens

An important way to reduce the severity and frequency of your allergy attacks is to avoid allergens and irritants that make them worse. Many of them exist in the home and here are a few suggestions to reduce your exposure to them.

HOUSE DUST

House dust has been recognized since many centuries as one of the major causes of allergic asthma and allergic rhinitis. It is unique among airborne allergens in that it is prevalent in the atmosphere throughout the world and present even in the cleanest room. House dust is a mixture of materials both living and non-living. It consists of human scales, dried disintegrated parts of domestic insects likes flies, mosquitoes and cockroaches. It also contains particles of wool, cotton, bed clothes, cracked paint, fibers from furnishings, bird feathers, flakes and fur of animals. It is now well known that the most important allergenic component of house dust is the house dust mite. Patients with house dust and house dust mite allergy usually have bouts of sneezing an watery nasal discharge and / or asthmatic attacks when bedroom dust is disturbed by shaking the bedding or switching on the fan which churns up the dust. Attacks usually occur early in the morning or just awaking from sleep. The patient is much better when he is outdoors where house dust exposure is less.

 HOUSE DUST MITE

House dust is composed of small particles of paint and animal material in the home. While this mix is not appealing to us, microscopic creatures called house dust mites thrive in it. The droppings of these mites are the most common trigger of perennial (round the year)allergy and asthma symptoms. Dust mites are found throughout the house, but they especially thrive in high humidity and in areas where human dander (dead skin flakes) is located. It measures approximately 0.1 mm in size and is invisible to the naked eye. It thrives in the human environment and is therefore found wherever human beings live and especially where they sleep. It feeds on remnants of house hold food and especially on the skin scales shed by human beings. Every minute, 40,000 dead skin cells fall from our body. 70% of the dust in our home consists of shed human skin.

Each of us sheds approximately 5 grams of skin scales and hair every week. 1 gram of this accumulates in the bed and bed clothes – an amount that can support upto 10,000 mites. In the bedding, upto 400 mites may be found in 1 gram of dust. Not only mites but their excreta and dead mites are allergenic.

Symptoms of dust mite allergy can include a. congested or runny nose with sneezing (particularly in the morning), itchy, watery eyes, coughing and wheezing. .

To reduce dust mites, it is important to control humidity to below 50 % throughout the home by using a dehumidifier or central or window or air conditioning.

Wall-to wall carpeting should be removed as much as possible, especially that which is laid over concrete floors. Hardwood, tile or linoleum is better for those with allergies. Washable throw rugs may also be used if they are regularly washed in hot water.

Because people spend more time in the bedroom than in any other room, it is essential to reduce mite levels there.

Cover mattresses box springs and pillow in airtight zippered plastic or special allergen-proof fabric covers. Bedding should also be washed weekly in hot water ( 130 degrees F ) and dried in bright sun light. Mattresses should be aired regularly at least once a week. Pillow and razias ( comforter) made of natural materials such as down feathers or cotton should be replaced with items made from synthetic fibers or covered with allergy-proof encasings.

It is also best to have smooth, uncluttered surfaces with dust collecting objects placed in drawers or closed cabinets. Avoid using the room where you sleep as a library or study. .

Weekly vacuuming can help to further remove dust mites. Those with allergies should use a vacuum with a HEPA ( high efficiency particulate) filter or a double bag, since using standard or water filtered vacuum cleaner stirs dust up into the air. Allergic individuals should also wear a dust mask while house cleaning.

House dust mites live in textile items preferably in deeper zones of the mattresses, carpets, upholstery and clothing. They live where people live even in excellent hygienic or unhygienic conditions and are not seasonally restricted. Allergenic character of mites shows cross reactivity with crustaceans ( shellfish) and insects. They are implicated as triggering factor in as many as 70 % of allergic asthma cases. Cross reactivity between mites and grass pollens has been observed. Remove carpets from bed rooms, dry clean all other carpets in the house, clean heavy drapes and dust regularly. Expose mattresses to sunlight, use mite proof sheets/pillow covers.

Oral vaccines against House Dust Mite allergy are now available.

MOLD CONTROL

Mold is commonly found in outdoor air. However, any house can develop a mold problem given the right conditions. You might not see it growing on walls, but it may still be present in your home. Molds require two factors to grow indoors.

1.) Free moisture that can occur in the form of relative humidity above 5.0%.

2.) Something to grown on like food, fabrics, in bathrooms behind the sink, toilets, tubs, washing machines, leaking roofs, poorly sealed basement, refrigerator drip  pans, air conditioner reservoirs.

These areas should be cleaned regularly and repaired. House plants, stuffed toys, wool carpets should be removed as far as possible. Mold colonies grown on the side of the house, windows next to outdoor plants debris or out side walls that are covered by or adjacent to growing plants. Hence as far as possible keep this area clean. Seal clothing, mattresses and pillows in plastic bags. Use synthetic furnishings. Indoor humidity can also be controlled by good ventilation, bright lights and air conditioning.

Unlike pollen, mold do not have a specific season, but are affected by weather conditions such as wind, rain or temperature. Outdoor mold spores begin to appear and reach their peak in July in warm states and October in cold. Common airborne molds include Alternaria, . Cladosporium and Aspergillus.

People allergic to mold should avoid fermented foods, beer, mushrooms, etc. Use of cleaning solutions containing 5% bleach and small amount of detergent is recommended.

FUNGUS/MOLDS

Alternaria This is a second most common fungal spore found in the atmosphere on dry days commonly seen on ripening cereal and during harvest time. It is associated with bakers asthma and atopic dermatitis ( skin allergy).

Aspergillus Fungus commonly found in humid tropical areas and associated       with atopic dermatitis, asthma and alveolitis. Cross reactive with Candida.

Penicillum This fungus is associated with climatically cold conditions e.g. in humidifiers and air conditioners. It is commonly implicated in atopic dermatitis and find a good nutrient source in the form of paint, wool, cotton, and food scraps.

Cladosporium It is the most widely found universally present airborne fungal spore limited largely to cool dry seasons.

Candida There is a wide cross reactivity between various fungi and food mainly wine, cheese, beer and other fermented foods. It is commonly found on mucosal surfaces and cross reacts with Aspergillus

 

Botrytis Fungus associated with dry dusty areas. Cross reacts with Aspergillus fumigatus

Mucour Mold seen in bakeries, on floor, wood, dust and dried fruit.

In general for those allergic to fungi ( molds) like Alternaria, Aspergillus, Penicillum, Candida, Cladosporium, Botyritis etc. should follow these restrictions.

1.       Remove all damp area on wall by white washing

2.       Eat fresh food/ not left over food especially bread and roti

3.       Avoid using wet towels/ shoes/ socks and dry well before use.

4.       Dust the house regularly.

TREES GRASSES AND POLLENS

Pollens are the tiny, egg-shaped male cells of flowering plants. These microscopic .powdery granules are necessary for plant fertilization. The average pollen particle is less than the width of an average human hair. Pollens from plants with bright flowers such as roses, usually do not trigger allergies. These large, waxy pollens are carried from plant to plant by bees and other insects.

On the other hand, many trees, grasses and low growing weeds have small light, dry pollens that are well suited for dissemination by wind currents. e.g. Parthenium (congress grass), Lawsonia (mehndi), Bermuda grass (dhoob grass ).These are the pollens that trigger allergy symptoms. Each plant has a period of pollination that does not vary greatly from year to year. However, weather conditions can affect the amount of pollen in the air at any give time.

Generally the pollen season lasts from February or March through October.

Tress pollinate earliest, from February through May. Although this may fluctuate in different location starting in April in colder northern regions or as early as January in the south. Grasses follow next in the cycle beginning pollination in May and continuing until mid July. Weeds usually pollinate in late summer and early autumn.

COMMONLY FOUND POLLEN  ALLERGENS AND WHERE THEY ARE FOUND

 

 

POLLEN ALLERGEN               SITE / CROSS REACTANTS

 

 

Eucalyptus People allergic to pollen trees should avoid spices belonging to family anise, caraway, coriander (dhania), cumin, (jeera) parsley.

Parthenium Cross reacts with ragweed.

Pine Tree / Acacia The trees share common n-glycans, liquid transfer proteins Profilins (panallergens) with other nuts, e.g. cashew nuts, hazelnut, coconut, and recently reported cotton.

Mugwort /Artemesia This is a widely distributed weed in parks & gardens. It cross reacts with various fruits, e.g. melons, lychees, and vegetables like cucumbers, carrots.

Grass Smut / (Dhoob Grass) Bermuda Grass is seen in sub tropical areas. Pollination seasons from April to end August. It cross reacts with rye, tomatoes, carrots, wheat, raw potatoes, soybean, peas and peanuts. Individuals allergic to grass should avoid cereals during the harvest season.

MISCELLANEOUS

Latex

It is an active compound in rubber items e.g. gloves, chappals, condoms, elastic etc. It cross reacts with various fruits and vegetables e.g. papaya, bananas, avocados, kiwi fruit and berries, plums, tomatoes, potatoes, chestnut ( singhara).

Exercise

This acts as a cofactor in precipitating asthma attacks if allergenic food is ingested prior to an exercise program.

PREVENTING FOOD ALLERGIES

Food allergies can cause severe allergic reactions, ranging from rashes to complete systemic failure ( called anaphylaxis ).

The major strategy for preventing food allergies is to completely avoid or delay exposure to potentially allergenic foods and liquids for a month. This can be followed by gradual reintroduction done one at a time to see which particular food they are sensitized to. Please bear in mind foods are rarely taken in isolation and there may be many hidden additives in and various combinations in the food that we eat.

The only way to tell for sure whether you have intolerance is to eliminate suspect foods from your diet for five to ten days. Then reintroduce them one by one to see if they spark symptoms, which you should notice within a couple of hours and may last from a few hours to a day or so.

Keeping a food dairy will help identify culprits. Leave five days between reintroducing foods. .

Once you’ve identified troublesome foods, cut them out of your diet for three to six ” months. You may then be able to tolerate small quantities without provoking a reaction.

CONTROLLING HOUSE DUST MITES

House dust is composed of small particles of paint and animal material in the home. While this mix is not appealing to us, microscopic creatures called house dust mites thrive in it. The droppings of these mites are the most common trigger of perennial (round the year)allergy and asthma symptoms. Dust mites are found throughout the house, but they especially thrive in high humidity and in areas where human dander (dead skin flakes) is located.

Symptoms of dust mite allergy can include a. congested or runny nose with sneezing (particularly in the morning), itchy, watery eyes, coughing and wheezing. .

To reduce dust mites, it is important to control humidity to below 50 % throughout the home by using a dehumidifier or central or window or air conditioning.

Wall-to wall carpeting should be removed as much as possible, especially that which is laid over concrete floors. Hardwood, tile or linoleum is better for those with allergies. Washable throw rugs may also be used if they are regularly washed in hot water.

Because people spend more time in the bedroom than in any other room, it is essential to reduce mite levels there.

Cover mattresses box springs and pillow in airtight zippered plastic or special allergen-proof fabric covers. Bedding should also be washed weekly in hot water ( 130 degrees F ) and dried in bright sun light. Mattresses should be aired regularly at least once a week. Pillow and razias ( comforter) made of natural materials such as down feathers or cotton should be replaced with items made from synthetic fibers or covered with allergy-proof encasings.

It is also best to have smooth, uncluttered surfaces with dust collecting objects placed in drawers or closed cabinets. Avoid using the room where you sleep as a library or study.         .

Weekly vacuuming can help to further remove dust mites. Those with allergies should use a vacuum with a HEPA ( high efficiency particulate) filter or a double bag, since using standard or water filtered vacuum cleaner stirs dust up into the air. Allergic individuals should also wear a dust mask while house cleaning.

House dust mites live in textile items preferably in deeper zones of the mattresses, carpets, upholstery and clothing. They live where people live even in excellent hygienic or unhygienic conditions and are not seasonally restricted. Allergenic character of mites shows cross reactivity with crustaceans ( shellfish) and insects. They are implicated as triggering factor in as many as 70 % of allergic asthma cases. Cross reactivity between mites and grass pollens has been observed. Remove carpets from bed rooms, dry clean all other carpets in the house, clean heavy drapes and dust regularly. Expose mattresses to sunlight, use mite proof sheets/pillow covers.