Aeroallergensand

Climate Change

ALLERGENS

- is any substance that can cause an allergy. - In technical terms, an allergen is an antigen capable of stimulating a type-I hypersensitivity reaction in atopic individuals through Immunoglobulin E (IgE) responses. Sensitivities vary widely from one person to another.

ALLERGEN

AEROALLERGENS (aer·o·al·ler·gen)

- any airborne substance which triggers an allergic reaction.

Classified into three groups:

• pollen (tree, weed, and grass),• mold, and• indoor allergens.

- a fine powdery substance produced by the anthers of seed-bearing plants.

Aeroallergens include the pollens of specific seasonal plants causing allergy commonly known as hay fever.

POLLENS

Trees:such as birch, alder, cedar, hazel, hornbeam, horse chestnut, willow and olive.

Examples of plant pollen commonly responsible for hay fever include:

especially ryegrass and timothy .

*An estimated 90% of hay fever sufferers are allergic to grass pollen.

Grasses:

Weeds:

ragweed, plantain, nettle, mugwort, and sorrel.

Electron microscope image of pollen grains from a variety of common plants: sunflower, morning glory, prairie hollyhock, oriental lily,

evening primrose, and castor bean.

• Tip of a tulip stamen with many grains of pollen

• Close up image of a cactus flower and its stamens

SPORESIn fungi, spores of

many fungal species are actively dispersed by forcible ejection from their reproductive structures, which travel through the air over long distances.

Video 1: Mushrooms dispersing spores .

DUST MITE

Dust mite debris is the major source of allergens in house dust.

These microscopic arthropods primarily feed on human skin scales.

INDOOR ALLERGENS

Both the mite bodies and fecal pellets are major sources of mite allergens, which become airborne when disturbed.

CATS AND DOGS

- these animals are major contributors to indoor allergen exposure.

Felis domesticus, the major cat allergen, is produced primarily in the sebaceous glands and is secreted onto the skin and fur. This allergen is also present in the salivary glands.

The allergen is chiefly carried on small particles and remains airborne for long periods.

COCKROACH

Cockroach allergens are derived from saliva, fecal material, secretions, and dead bodies of cockroaches.

Aeroallergens and Climate Change

Changes in climate could impact the production, distribution, and dispersion of aeroallergens; allergen content; and the growth and distribution of the weeds, grasses, tress, and mold that produce them.

CO2 concentration - acts as a fertilizer for

plant growth, thus increasing pollen production and the allergen content of pollen grains.

precipitation and temperature

- also led to enhanced pollen production.

1. Aeroallergen Production

2.Timing of Aeroallergen Production

Higher temperatures and humidity

- changing the timing and duration of the pollen season.

Phenologic advance is likely to occur for numerous species of plants, especially trees.

3. Distribution and Dispersion of Aeroallergens

There will likely be changes in the distribution of pollen producing species, including the possibility of extinction in some cases.

Intercontinental dispersal is possible, facilitating the introduction of new aeroallergens into other areas.

4. Allergenic Content of Aeroallergens

influence of meteorological variables, such as temperature and precipitation, and air pollutants, such as CO2, on the concentration of allergen protein of pollen.

Prevention/AdaptationZero Order Prevention:

Decrease emissions of and/or increase sinks for greenhouse gases

enhancing greenhouse gas sinks and decreasing greenhouse gas emissions that lead to global warming.

decrease carbon footprints and encourage others to do the same

Primary Prevention:Reduce exposures to aeroallergens

Monitor aeroallergen and ozone alert forecasts and minimize exposures

Use of HEPA filters should be encouraged for asthmatics to decrease penetration of aeroallergens into the home

Advise asthmatic patients to avoid overexertion and/or excessive time outdoors during days of high pollen counts and air pollution

Create and implement education programs about the importance of allergen avoidance for allergy sufferers, particularly asthmatics

Design and protect landscapes that produce lower levels of aeroallergens within the context of local ecology

Secondary Prevention:Prevent onset of allergic illnesses

Use allergy and asthma medications as prescribed

Check pollen forecasts and avoid excessive time outdoors on high pollen days

Advise patients on the correct ways to prevent onset of allergies through medications

Communicate the importance of limiting exposure on high pollutant days

Tertiary Prevention:Treat allergic illnesses

Seek medical help if necessaryEnsure medications are widely available

FungiReduce spore infiltration

- windows and doors should be kept closed as much as possible.

Moisture control- Repair leaks, use air conditioning at times of high humidity, ventilate bathrooms and kitchens, and heat all rooms in the winter.

Cleaning - use detergent solution with 5% bleach

Air filters - HEPA filters

Masks - a pollen mask is useful during activities such as cleaning and vacuuming

Dust mitesImpermeable covers

-composed of either vinyl or tightly woven fabric and serve as effective dust mite barriers.

Elimination of dust reservoirs-remove stuffed toys, books, or other items that collect dust, particularly in the bedroom.

Vacuuming- Weekly vacuuming is recommended, and vacuum bags should have 2 layers or a HEPA filter to decrease aerosolized allergen exposure because of the air disturbance.

Washing - Washing linens in hot water (55°C [131°F]) at least weekly is recommended to kill the mites and remove most of the associated allergen.

Air purifiers Freezing

- Dust mites die when frozen; therefore, stuffed toys and other such items can be placed in a domestic freezer to decrease dust reservoirs.

Acaricides- Disodium octaborate tetrahydrate (DOT) is safe for humans and effectively kills mites.

Relocation - high altitudes or arid locales are associated with less mite growth.

Cats and DogsRemoval of the pet or Restrict pet access

- pet should be kept outdoors.Washing the pet

- wash the pet at least twice weekly.Air purifiers

CockroachesPesticides

- Pesticide spray is effective, but selective placement of gels or baits is preferred.

CleaningElimination of food and water supply

- Food should be stored in sealed containers, and any sources of standing water should be removed.

REFERENCES:http://en.wikipedia.org/wiki/Allergenshttp://en.wikipedia.org/wiki/Aeroallergenhttp://cfpub.epa.gov/ncea/cfm/

recordisplay.cfm?deid=190306http://www.ncbi.nlm.nih.gov/pubmed/15479264http://www.ncbi.nlm.nih.gov/pmc/articles/

PMC2880235/http://emedicine.medscape.com/article/137911-

overview#aw2aab6b4http://www.123rf.com/photo