Prevention at Home

Until 1985, materials obtained from house dust were commonly used for skin testing and immunotherapy. Any foreign species that exists in the indoor environment can be a source of allergens found in materials from house dust. Many allergists have given up on skin testing with house dust for two reasons. First, there was a feeling that we had a better understanding of the main sources of indoor allergens (debatable), and second, it became clear that it was not possible to standardize house dust (true).
Most of the major sources of indoor allergens are well known, including dust mites, cats, dogs, rodents, cockroaches, and a variety of fungi. In addition, for many of these, there are sensitive immunoassay tests that can measure the amount of allergens at home.
Despite the existence of some problems in immunoassays, including the difficulties in performing them and the details of their characteristics, there is no substitute for them in determining the number of indoor pollens.
Allergen-carrying particles from mites, cockroaches, cats, or dogs are not specific enough to allow counting under a microscope.
It is also not possible to count the number of airborne particles in the indoor air, because the particles that carry mite and cockroach allergens do not remain suspended in the air for more than a few minutes.
Cat and dog allergens remain suspended in the air for a longer time due to their smaller aerodynamic size. However, it is still not possible to count the particles of cat or dog dander microscopically.

1. There is no carpet on the floor of the room and the use of ceramics and parquet. Using a HEPA vacuum cleaner, having enough light and normal humidity.
2. Using chemicals such as Bleach solution to remove fungi and benzyl benzoate and tannic acid to kill mites.
3. Using Dacron covers for pillowcases and bedding. 4- Washing everything that can be washed, even the ceiling fan.
4. Absence of carpet in the bedroom and living room (ceramic, parquet or cotton floor is not an obstacle) Removal of pillows from birds and other pets at home, serious fight against cockroaches, ants and other insects, not being present when sweeping (even a vacuum cleaner) covers for mattresses and pillows, washing and changing sheets (weekly), not using natural flowers in the patio, bathroom and toilet, ventilation and kitchen hood being light-proof.

Some organisms and substances inside the house or place of residence (such as cockroaches, animal waste, etc.) that cause allergies or sensitivity are known as indoor allergens. Allergy to these substances usually occurs in It can be seen all year round.
Every year, millions of people suffer seasonally from the symptoms of allergies such as congestion, runny nose, and inflammation of the nose and eyes. Also, some people suffer from permanent allergies caused by indoor allergens such as mites, cockroaches, mushrooms, and animal dander. .
Mites:
Dust in the house is a combination of small particles of plant and animal matter.
The main place of growth of microscopic organisms called mites is in house dust.
These organisms are the most common cause of permanent allergies and asthma. Mites are seen in places in the house, especially in humid places and places where human body dander (poor dead cells) exist.
These microscopic creatures cannot be seen with the naked eye and have
a size of about 1-30 microns
(0.03-0.001 mm).
Symptoms of mite allergy include congestion or runny nose with sneezing (especially in the morning), red and watery eyes, cough and wheezing.
To reduce the growth of mites, it is necessary to prevent the increase of humidity in the house as much as possible. Try not to exceed 50% of the humidity inside the house (the air humidity of cities like Tehran, Mashhad, Isfahan and Shiraz is around 50% most of the year). To reduce the amount of humidity, the following recommendations can be used:

• After cooking, washing and bathing, open the windows or doors of the kitchen and bathroom for ventilation or use strong air conditioners.
• If the air in the room is not ventilated to the outside, avoid drying the washed clothes inside the rooms.
• To heat the house, use a heating system that has proper air conditioning.
• To reduce the growth of mites, avoid covering the entire floor with carpet.
• Washable rugs can also be used (of course, the rugs must be washed regularly with warm water).
• Covering the floor with wood is better for people with allergies.
• Since people spend a lot of time in the bedroom, it is necessary to try to limit the growth of mites there as much as possible.
• The top of the bed should be washed weekly with hot water (65 degrees Celsius) and then dried with heat.
• Choose sheets, mattresses and pillows preferably made of synthetic fibers (not wool or cotton) and wash them regularly.
• Do not use your bedroom as a library or study place.
• Vacuuming every week can help remove mites from the habitat. Allergic people should use High-Efficiency Particulate Absorption-HEPA filters or double-walled bags for their vacuum cleaners.

Pets:
It seems that people are not allergic to animal hair, but to proteins found in saliva, urine or dead parts of animal skin.
These proteins are transmitted in the form of very small particles in the air and directly contact the nose or eyes or enter the lungs.
Tolerance to cat or dog allergens:
In several studies on sensitivity, it has been shown that children who grew up in homes with animals are either less sensitive to that animal or not more sensitive than usual.
Although the mechanism of this tolerance is not clear, there are reasons why these children develop IgG and IgG4 cat allergens.
It has also been determined that children with IgG and IgG4 without IgE are not at risk of developing asthma.
Symptoms of allergy to animals include sneezing, runny nose, swelling of the eyes and throat, redness of the skin or prominent red spots on the skin that appear after contact with the animals in question.
Usually, such symptoms appear quickly and may worsen dangerously within 8 to 12 hours. 
A bird, rabbit, dog or cat produces a certain amount of allergen during the week and this amount varies from animal to animal.
But all species of these animals have the ability to cause symptoms, and there is no species that is less allergenic.
The most effective way to prevent and control this type of allergy is not to keep pets at home and avoid any contact with them. Moving the animal out of the residence (rooms) is only a partial solution, because the yard where the animal is kept is contaminated with a large amount of allergens of that animal.
Before you bring an animal home, spend some time with someone else’s animal to assess your allergies.
If you are allergic to an animal that you keep at home, you should get rid of it, although it may be difficult, but it is necessary for your health.
If contact with pets is unavoidable for you, try to minimize this contact and prevent them from entering your bedroom.
Weekly washing of pets reduces the release of allergens in the environment.
Be sure to consult a veterinarian to wash your animals to prevent excessive drying of the animal’s skin.
Also, ask a non-allergic member of the family to comb the animal’s hair to remove loose hair from the animal’s skin.
The origin of allergens in dogs and cats is saliva and hair, in rabbits and mice, urine and in birds, feathers separated from their bodies.
Sweeping the living environment with a vacuum cleaner does not play a big role in removing animal allergens, instead, using stone and flooring instead of carpets plays a significant role in reducing these allergens.

Cockroaches:
Cockroaches have a lifespan of about 300 million years in nature.
They mostly live in warm tropical areas, but different species of them are also found in human homes and places of residence. Cockroach excrement proteins can cause asthma symptoms, especially in children. 
To reduce asthma symptoms, cockroaches should be removed from your residence.
The most important areas from which cockroaches can enter the house are: toilets, cracks in the walls, windows, cracks in the floor or entrance doors.
Bathroom cockroaches need water to survive and live in wet places, so try to fix leaking pipes and faucets.
Cockroaches are less common in clean homes.
So try

1. Keep your leftover food in full packages.
2. Wash dishes immediately after eating.
3. Always keep the surfaces and floors of the kitchen clean and dry.
4. Be sure to wash your pet’s food bowl thoroughly after eating
5. Clean the floor with a vacuum cleaner and disinfectant
6. Always use a trash can and a special bag for it in the kitchen.

Molds:
Molds grow indoors in moist places such as the basement and bathroom windows.
These molds release small spores that cause allergy symptoms.
Fortunately, indoor molds are easy to remove.
This can be done using a solution containing 5% bleach and a small amount of detergent.
Repair damp ceilings and leaky water pipes to reduce humidity and prevent mold growth.
Never spread your carpet on a concrete or wet surface and avoid storing clothes, cloth and paper in wet places.
Using a dehumidifier is effective in wet basements, but it cannot reduce the humidity in the whole house.
Remember that all rooms, especially basements, bathrooms and kitchens, need proper ventilation and constant cleaning to prevent the growth of mold and fungus.

In order to reduce the symptoms of allergies in affected people, it is necessary to control the indoor environment of the house and especially the places that are suitable for the growth of indoor allergens. By conducting skin tests, the doctor will be able to identify the type of allergen you are allergic to and give you recommendations to reduce the amount of this allergen at home and, if necessary, to reduce your symptoms with drugs such as antihistamines. use decongestants or anti-asthma drugs.
Making changes in the interior of your life can be time-consuming, but to begin with, it is better to prepare a list of the changes that should be made in the interior of your home and residence in order of priority, so that by doing it, you can create a cleaner, healthier and allergy-free environment. Create less fertility for yourself and family members.
Estimation of exposure to indoor allergens:
Measurement of house dust proteins is usually expressed in micrograms per gram of dust.
This method enables comparison between houses as well as countries.
However, the use of these measurements in each home specifically identifies the first or only significant exposure to indoor allergens in each home. There are several reasons why allergies to cat and dog allergens can occur outside of a child’s home.
Also, it is more likely that allergy to dust mite allergens can be caused by contact in other houses.
It is possible to measure the amount of inhaled allergens using different methods.
For cat or dog allergens, the amount of inhaled allergens is about 1 microgram per day, and the amount of contact with cockroach mites is about 5 to 20 nanograms per day, that is, 50 times less. Comparison of exposure to inhaled cat allergens in homes with pets, without pets or in schools can be reliable.
On the contrary, it is very difficult to compare the amounts of airborne mites in different conditions, because it is difficult to standardize the level of exposure. Values ​​that are suggested as risk factors or thresholds for sensitization or pathogenicity should be interpreted with caution.
Threshold values ​​of chemicals are based on their toxicity level. Inhaled allergens are not toxic unless a person is sensitized to them. Therefore, it is possible to propose allergen exposure thresholds for sensitization and separate thresholds for asthma symptoms among sensitized individuals.
However, there are people who are sensitized with amounts much lower than these thresholds and show symptoms.
Likewise, a large number of non-atopic people (50-70% of the population) are not sensitized and do not show symptoms even when exposed to allergens with amounts 50 times the threshold.
Although the concept of risk factor can be used for various types of contact, this term is mostly used for contact with indoor allergens or sensitization to indoor allergens, as a risk factor for developing asthma.