Is bronchitis transmitted by airborne droplets? Is it possible to get bronchitis or not?


When cold weather sets in, the risk of acute respiratory viral infections, bronchitis, and influenza increases. With absence necessary treatment These diseases can cause significant complications. Against the background of the flu, otitis media, heart failure, and bronchitis can develop. It is bronchitis that we will now talk about.

Can you get bronchitis?

Probably each of us in a specific life situation asked the question: “Is bronchitis contagious or not? What is the likelihood of me contracting bronchitis from another person? These questions arise both at home and at work, at school, when we communicate with a coughing person. We hope for chance and sometimes it doesn’t work out. So what to do?

Doctors put forward two causes of bronchitis in origin - viral and bacteriological. In the first case, bronchitis is caused by influenza viruses and vapors. Secondly – ​​streptococci, pneumococci and so on. Very rarely, the cause of bronchitis is exposure to an allergen or toxic substance (such bronchitis is not at all contagious).

Is bronchitis contagious? The answer is yes. The main route of infection for bronchitis is airborne. When you inhale infected droplets of saliva (they are not visible in the air, but they are there), when you come into contact with a sick person, when you sneeze, cough, when talking and during a yawn - at any moment a virus that develops bronchitis can enter your body.

For example, the process of sneezing allows your body to cleanse the mucous membrane of the pulmonary alveoli and lungs from excess phlegm and dust particles. The speed of the released air is 150 km/h.

Now you need to understand that when you sneeze or cough, millions of invisible droplets that are infected with the virus are released into the air. In crowded areas, these droplets can easily enter the respiratory tract of others. In case of poor ventilation, the likelihood of contracting bronchitis increases significantly. That is why it is so necessary to comply simple measures precautions. Such events include the most banal things that we were told more than once in childhood: ventilating a room in which there are many people; covering your mouth and nose with a handkerchief when sneezing and coughing; After visiting public places, you must wash your hands.

There are some microorganisms, for example, the smallpox virus, that resist drying, so it persists even in dust. It would seem like dust, but it was infected with smallpox, but it still played its role.

Even during a conversation, microscopic droplets of saliva fly out of your interlocutor’s mouth. This is quite enough to become infected with bronchitis. Hence, we can say with confidence that bronchitis is a contagious disease. Whether you get sick or not depends on your immunity, as well as on whether you followed the usual precautions. By following these basic measures, you can significantly reduce the risk of disease.

If you do become infected with bronchitis, then there is no need to panic. Contact your doctor immediately to determine the exact disease and prescribe the necessary course of treatment.

General symptoms of bronchitis

The main clinical symptoms of chronic bronchitis include:

  • A scanty amount of viscous sputum,
  • Dyspnea.

During the course of the illness the patient is bothered by hard breathing, dry snoring, having a different timbre. In the presence of sputum, silent moist rales are characteristic. In order to exclude more severe pathology, such as lung cancer or tuberculosis, sputum is taken from the patient for examination. In chronic bronchitis, the composition of sputum is unremarkable. When conducting x-ray examination no specific data is noted. As a rule, it is used to exclude other diseases.

The main symptoms of acute bronchitis include:

  • Increased body temperature.
  • Fever, the duration of which depends on the type of pathogen.
  • A dry and obsessive cough is at the beginning of the disease, wet and productive at the end.

Conclusion

Bronchitis is a disease that causes inflammatory nature. It is quite possible to become infected with this disease. The main method of infection is airborne droplets. To prevent infection with bronchitis, you must remember and follow the rules of personal hygiene.

Bronchitis is an inflammation of the bronchial mucosa, one of the most common diseases respiratory tract among children and adults. In the vast majority of cases this pathology is infectious and can be caused by bacteria and viruses.

According to the classification, there are acute simple and obstructive, as well as chronic variants of bronchitis. The causes of the acute form of the disease are:

  • Viral agents (influenza, parainfluenza, rhinovirus, enterovirus, adenovirus).
  • Bacteria (staphylococci, Haemophilus influenzae, chlamydia, mycoplasma).
  • Fungi (candida, aspergillus).

All of these infections are dangerous to others and can be transmitted from a sick person or carrier to a healthy one. This means that you can become infected through direct contact with the source of infection, i.e. by:

  • Being in the same room.
  • Living in a shared apartment.
  • Traveling on public transport.

Can you get infected from a sick person?

You can only get bronchitis from another, sick person, or when your own microflora is activated against the background of a decrease in the body's defenses.

Most often, the infection is transmitted from a person who coughs and sneezes. In the process of breathing, a healthy person inhales air along with pathogenic microorganisms, they settle on the mucous membranes of the respiratory tract. An infected person will receive the viruses or bacteria that caused illness at the source of the infection, but this does not mean that he will necessarily develop bronchitis.

Many of the viruses can infect not only the mucous membranes of the bronchi, but also the pharynx, larynx or trachea, which means that upon contact with a person suffering from bronchitis, both bronchitis and pharyngitis, laryngitis and tracheitis, and in some cases even pneumonia, can develop.

Some people, after contact with someone with bronchitis, do not develop respiratory diseases; in this case, it all depends on the individual’s immunity.

Transmission routes

There are several routes of transmission of acute respiratory infectious diseases, which include bronchitis. Here are the main ones:

  1. Airborne. The most common route of transmission of respiratory diseases. When coughing, sneezing and during conversation, microscopic droplets of sputum and saliva containing a large number of viruses or bacteria. These particles of moisture with pathogenic microorganisms are inhaled by another person and settle on the mucous membranes of the respiratory tract. When the body's resistance decreases, pathogens begin to multiply intensively, which leads to the development of the disease.
  2. Contact route of transmission of infection. Occurs when a sick person sneezes or blows his nose into his fist, and then, without washing his hands, touches various surfaces, greets (shakes hands) or hugs other people (healthy). Some pathogens can remain viable in the environment for a long time and become a source of illness for other people. After getting an infection on your hands healthy person, he only needs to touch his face, mouth, or simply rub his eyes for infection to occur.

Also, some experts believe that you can become infected by using common utensils and cups.

The contact route of transmission is considered more dangerous than airborne transmission, since with it microorganisms do not need to overcome a large number of natural protective barriers, as happens with the airborne mechanism of infection.

Is it transmitted by airborne droplets or not?

Airborne droplets are the most common route of transmission of all respiratory diseases. In this way, acute infectious and obstructive infectious bronchitis is transmitted, as well as chronic inflammation bronchi caused by viruses, bacteria and fungi.

There are also non-contagious variants of bronchitis - allergic, reactive and dust. Since they are caused not by microorganisms, but by other factors, these species are not transmitted from a sick person to a healthy person, and therefore are not at all dangerous to others and cannot be transmitted through the air.

Acute infectious

Most often (in 85% of cases) simple acute bronchitis occurs as a result viral infections. Main symptoms of the disease:

  • Increased body temperature.
  • Discomfort, chest pain, worse when coughing.
  • Painfully dry and then moist cough, with the release of mucous or mucopurulent sputum.
  • Catarrhal phenomena - nasal congestion, runny nose, pain and sore throat.
  • Signs of intoxication – headache, muscle aches, general weakness.

The severity of the disease depends on the age of the patient, general condition his health and defenses of the body. Average duration acute bronchitis in people without concomitant diseases is 2–3 weeks. Residual cough may persist for 10-14 days after recovery.

The length of time a patient remains contagious depends on the virus that caused the disease. On average, bronchitis is contagious to others throughout the entire period of fever and severe cough.

Chronic

Diagnosis Chronical bronchitis is indicated when symptoms of the disease such as cough with sputum production, chest pain and weakness persist for 3 months in a row.

The transition from acute to chronic bronchitis is more often diagnosed in people with risk factors:

  • Long-term smoking abusers.
  • Those with concomitant pathologies of the bronchopulmonary system (COPD, asthma, tumors).
  • Working in hazardous industries.
  • Living in unfavorable conditions (dust, atmospheric pollution).

Chronic bronchitis can occur as follows: sluggish form, and in the form of alternating periods of exacerbation and remission.

Obstructive

Spicy obstructive bronchitis more common in children than in adults. This is due to the structural features of the respiratory tract in infants.

With this variant of the disease, a spasm of the respiratory muscles in the bronchi occurs, as a result of which the mucus cannot leave the lumen of the respiratory tract, a paroxysmal painful cough occurs, shortness of breath, and respiratory failure develops.

In addition to infants, this form of the disease is typical for patients with bronchial asthma, elderly patients with severe chronic pathologies heart and lungs, smokers.

Is it dangerous for children?

Like any other contagious infection, bronchitis is dangerous for children. Moreover, due to immaturity immune system Children suffer from bronchitis more often and more severely than adults and take longer to recover after recovery.

Acute bronchitis in children it is caused by viruses and bacteria, and also occurs with diseases such as whooping cough, rubella and measles. Simple acute bronchitis in early age occurs with the same symptoms as in adult patients - cough, fever, weakness and intoxication.

Obstructive bronchitis develops in every fourth child before he reaches 3 years of age. The pathology is characterized severe course with a strong, increasing cough, shortness of breath, development oxygen starvation. Without proper treatment The obstructive form of bronchitis can lead to serious complications such as bronchiectasis, emphysema, and even death.

Bronchitis is one of the most dangerous diseases respiratory tract in children, therefore, if signs of the disease appear, it is important not to self-medicate, but to consult a doctor for diagnosis and selection of effective therapy.

Bronchitis is a fairly common disease that every person has encountered at least once in their life. This is an inflammatory procedure associated with inflammation of the bronchial walls, occurring under the influence of unfavorable factors of various nature.

Many people do not know that bronchitis is a rather serious illness that can develop into asthma or a chronic disease.

What is acute bronchitis?

This is a condition that manifests itself in breathing and affects the mucous membranes. Easily appears on its own, under the influence of various infections. Development is influenced by inflammatory processes that occur in respiratory system. When damaged, the passage of oxygen through the bronchi is disrupted, resulting in severe swelling of the mucous membranes.

Bronchitis (acute) lasts from 7 to 14 days, after this time, with effective treatment, the disease recedes. Sometimes it can become chronic.

Treatment should occur in combination:

  • Taking medications (against inflammation and cough).
  • Carrying out physiotherapy (electrophoresis, massage in the area chest, Ural Federal District).

With complex treatment, the prognosis for recovery is usually favorable and largely depends on timely procedures. According to statistical data, this has become widespread, with patients being seen at medical institutions for qualified help. More often, children are affected, whose age is up to 14 years (more than 60% of the total volume), adult representatives, as a rule, are male, age category ranges from 30 to 50 years.

Every year, more than 20 million cases of this serious disease are recorded. Due to not seeking medical help for a long time, or due to lack of necessary treatment, more than 80 thousand people die every year.

The reasons are the following:

  • Penetration by airborne droplets, or through exposure to elementary contacts (during conversation).
  • Presence of viral infections.
  • Presence of harmful habits (drinking alcohol, smoking tobacco, etc.). This also occurs in non-smoking people who are in close contact with smokers.
  • Breathing various allergens (dust, pollen, gases).
  • Hypothermia.
  • Work activity in hazardous enterprises (woodworking, chemical, metallurgical).
  • Heredity.
  • Weak immunity.

Contagious or not?

Many people are interested in the question of whether it is possible to become infected from a sick person and how the disease progresses. This is a condition of the mucous membrane when infections penetrate immediately into the body.

Development manifests itself in the initial period of inflammation. The main reasons include:

  • Various infectious ailments.
  • Physical or chemical factors(presence of dust, temperature changes, excess moisture).
  • Consequences of radioactive radiation.

Based on these reasons, it can be determined whether it is contagious or not. If the last two factors of the disease occur, it is impossible to become infected from it.

Many people are interested in the question, how does infection occur? You can easily become infected from a sick person by coughing (sneezing) - the disease is transmitted in this way. This is explained simply: the patient exhales, microbes are released, which, once in human body, hit him.

In what cases can it be contagious?

Microbes multiply on the mucous membrane and easily move into the body of another person through open air (when coughing, sneezing). The risk of injury increases significantly and only a doctor can make the correct diagnosis and determine whether this is a defeat for others or not.

The effect is of an acute nature, occurs as a consequence of complications, development occurs immediately after penetration into the body, sometimes after several days. The lesion may not be infectious in nature, may not pose a threat to surrounding people, and contact with sick persons will not cause infection with the disease.

This type includes:

  • Allergies arising from components of chemical production (dust, mold, all kinds of pollen).
  • Breathing exhaust gases, work activity in a hazardous enterprise, toxic irritants.
  • Disorders arising from breathing through the nose, due to a deviated septum (through the nose), or from taking vasoconstrictor medications.

Important! When affected, the sick patient has complaints about general weakness, cough, high temperature body, mucus coming out of the nose, wheezing (shortness of breath).

A type of infection (contagious to nearby people) is characterized by a dry cough, slight sputum production, normal temperature. The disease develops during inflammation of the mucous membrane.

There are several signs of determining infectiousness:

  • There is no runny nose.
  • No temperature.
  • There is a dry cough.

The infection is quite simple: you can become infected through the usual airborne droplets. This can be explained simply - when the patient coughs, he exhales and, together with microbes, phlegm will be released. It is noted that a sick person receives the same viruses. The immune system plays a huge role in this - if it is strong, damage may not occur.

Typically bronchitis acute type quite contagious. The infection, having reached its destination, begins its influence. A person can catch a cold, which can easily turn into bronchitis (with a weakened immune system).

  • The disease is quite dangerous for smokers;
  • patients with lung diseases;
  • those who breathe dirty air.

Most diseases come from germs and viruses, this will not bring improvement. They will only be effective if microbes enter the body, or if there is chronic bronchitis.

How does infection occur?

It should be remembered that damage occurs not by disease, but by infection. If a patient’s lungs become infected, we can conclude about the degree of contagiousness of the disease: it affects people with weakened immune systems. Such people become infected various ailments much more often than others. During the development process, viruses reach humans quite simply: by airborne droplets.

At the moment of sneezing, the bronchi are cleared of mucus, but the speed of movement of microbes develops up to 140 km/h. and a sick person can easily infect a healthy one. When talking (yawning), an unhealthy person can release microparticles of saliva, which are a source of damage.

People around should remember simple methods precautions:

  • Constantly ventilate your rooms.
  • Apply hodovoxoline ointment to the nasal area.
  • Wear a mask; it will effectively protect against various injuries.
  • After visiting public places (transport), wash your hands especially thoroughly with soap.
  • Try to communicate less with sick people.

Bacteria (viruses) are present in every person, they can for a long time not to manifest itself until a favorable environment for its development arises. This includes weakened immunity, impaired body functions, and unfavorable climatic or environmental conditions. It is necessary to find out whether the disease is infectious from a doctor who will prescribe tests and comprehensive diagnostics. It is he who will be able to make the correct diagnosis and prescribe.

If the presence of viruses is detected, a sick person should take all necessary measures to avoid infection by other infections: wear a protective mask, use a handkerchief or napkin when sneezing or yawning.

Bronchitis is a serious disease that occurs in an acute (chronic) form. The reasons are:

  • Presence of bacteria (viruses).
  • Excessive use of tobacco products.
  • Alternating exposure to contrasting temperatures in the air.
  • Constant penetration of gas (dust) into the body.
  • On the mucous membranes of the lungs there is a manifestation of sedimentation of substances (of a harmful nature).

The acute form refers to a contagious disease: pathogens, but not the disease itself, can travel from a sick person to a healthy person. For this reason, the affected person's symptoms may be completely different and look completely different. If you have a strong immune system, pathogens can be destroyed by the body itself, and the disease will not occur.

List of persons at increased risk:

  • Infants.
  • Women expecting a child.
  • Aged people.
  • Representatives of younger age.
  • Persons who have suffered major operations or serious illness.
  • Cancer patients.

If illness is detected in children, it should be remembered that germs enter the body in the same way as in adults. Here, the strength of the immune system plays the maximum role. If the baby is severe, the disease may pass superficially without affecting the lungs.

Infection with acute bronchitis proceeds slowly: first the nasal mucosa is affected (rhinitis is formed). The development procedure completely depends on the strength of the immune system: if it is weakened, the infection first penetrates the throat area, pharyngitis occurs, then penetrates inside and bronchitis is formed.

An acute illness is quite contagious: infectious microbes, having reached a certain level inside, begin their harmful effects.

Important! A person can catch a common cold, which after a certain period of time easily turns into bronchitis. This condition is very dangerous for smokers and people who inhale dirty air (at work).

Symptoms:

  • Hard breath.
  • Cough.
  • Sputum discharge.
  • There is severe pain in the chest area.
  • rises to 40 0 ​​C.
  • When breathing, a whistling sound occurs that can be heard quite well.

Need to know! A large number of diseases are caused by viruses; in this case, taking antibiotics will not provide improvement. They are taken only in the event of an infectious or chronic illness.

A respiratory disease in which inflammatory process localized in the bronchi is called bronchitis.

Reasons for the development of the disease

The reasons for the development of the disease are varied. Bronchitis can develop as a result of:
1. Entry of viruses of various etiologies into the patient’s body.
2. Bacteria.
3. Allergic reaction.
4. Ingestion of toxic substances into the body.
5. Various fungal infections.
6. Gas pollution in the room, increased dustiness.

Forms of bronchitis

The manifestations of bronchitis, depending on the course and nature of the disease, are distinguished:
1. Chronic.
2. Acute or obstructive. With this form it is noted acute inflammation bronchial mucosa, which causes an increase in the volume of sputum secreted. In the patient coughing. In addition, the patient experiences accumulation and stagnation of mucus, and breathing is difficult. Increased cough is observed in the morning and at night. Acute bronchitis is accompanied by an increase in temperature; the specialist notes wheezing while listening. The sputum has a yellowish tint.

Can others download it?

There are a number of predisposing factors that contribute to the development of the disease. These are: cold season, weakening of the immune system. At the same time, the risk of bronchitis increases.
The infection penetrates the bronchi and destroys the protective function. As a result: the mucous membranes secrete a large amount of sputum. The body tries to protect itself by producing mucus when coughing and sneezing. And due to this, the infection spreads to surrounding people. When an infection spreads to another patient, the action of the pathogen inside the body is unpredictable.
Whether bronchitis is contagious or not there is no clear answer. It all depends on individual characteristics body. The only thing that can be concluded is that the disease bronchitis itself is not contagious. Bacteria and viruses that are released during sneezing and coughing are contagious. The infection is transmitted by airborne droplets.

Is obstructive bronchitis contagious?

Obstructive bronchitis is an acute, severe form of the disease. Bacteria and viruses can be transmitted through airborne droplets. Initially, with the onset of symptoms, the specialist prescribes antibiotics, and additionally prescribes mucaltic agents that help cough up and remove sputum. Also drugs that help improve nasal breathing. It is also necessary to take bronchodilators, for example, ambraxol, bromhexine, and so on. Positive result Therapeutic gymnastics and massage promote a speedy recovery.
The disease itself is not contagious; we repeat, the infection is caused by viruses and bacteria that have settled in the body of a sick person. YOU CAN get infected with obstructive bronchitis! Since the mucus that is released from the body is infectious even in dried form. Infection occurs through contact with a sick person or through the use of household items.

Prevention and precautions

To prevent infection, you should follow a few simple rules:
1. Hygiene. Wash your hands constantly: after going outside, before eating.
2. Indoor microclimate. Do not forget to regularly carry out wet cleaning and ventilation.
3. Strengthening the immune system. To do this, you can start playing sports, eating right, and actively playing sports. You can think about the topic of hardening.
4. Every spring and autumn, take a multivitamin complex.
To summarize, it can be noted that obstructive bronchitis is a contagious disease. But by following all the rules of prevention, the patient protects himself from viruses and bacteria entering the body.

Bronchitis is an inflammatory process of the bronchial mucosa, which is caused by various factors. The disease is equally common among all age groups of the population. It causes a deterioration in the patient’s general condition and is accompanied by unpleasant symptoms in the form of cough with sputum, weakness, fever, decreased appetite. To help a loved one, but not to get sick yourself, it is important to know whether you can become infected with bronchitis.

The international classification distinguishes only two forms of this disease: acute and chronic. Among doctors, it is customary to classify it according to a number of other characteristics that help to navigate approaches to diagnosis and treatment:

  1. Due to the occurrence: viral, bacterial, allergic, fungal, mixed, toxic.
  2. According to the nature of inflammation: catarrhal, exudative, purulent, hemorrhagic, fibrous.
  3. According to the development of bronchospasm: obstructive, non-obstructive.
  4. According to the prevalence of the process: tracheobronchitis, bronchiolitis (inflammation of the small-caliber bronchi).

There is a stagnant type, which develops when the patient remains in a supine position for a long time, for example, in patients on mechanical ventilation ( artificial ventilation lungs).

The main role in whether bronchitis is contagious to others or not is played by the cause of its occurrence. The key factors in the development of the disease are:

  1. Viruses and bacteria. Among microorganisms, opportunistic and pathogenic are distinguished. This means that the latter will cause the development of the disease in most people, and the former only in the presence of accompanying factors (decreased immunity, hypothermia, etc.).
  2. Allergy. Allergic bronchitis develops only in people who are sensitive to certain airborne allergens (pollen, wool).
  3. Fungal. Occurs less frequently than others. Manifests itself in citizens with weakened immune systems, for example, after prolonged antibacterial therapy, taking cytostatics, in the presence of HIV infection.
  4. Toxic. The cause is inhalation of harmful gases and impurities. Unlike allergic form, which develops only in predisposed people, exposure to such toxic products will cause inflammation of the bronchi in any person.

Can others become infected with this disease?

There is no consensus as to whether bronchitis is contagious or not. A specialist can accurately say about the possibility of transmission of infection after establishing the form and cause of bronchitis.

A person with inflammation of the bronchi can not transmit the disease itself to others, but only an infection (bacteria, viruses). They are spread by airborne droplets or with saliva (through kissing). Thus, upon contact with a patient with bronchitis caused by staphylococcus or streptococcus, a person may develop a sore throat, pharyngitis, laryngitis or even pneumonia.

Each bacterium has its own infectivity; accordingly, the development of the disease is influenced by the properties of the microorganism, its stability in the environment and other factors.

As for the allergic form, it is impossible to become infected with it. For its development, sensitization to allergens is necessary, which triggers the inflammatory process.

What form of bronchitis is contagious?

You can only become infected if the disease is caused by infectious cause, and a person has accompanying factors in the form of reduced immunity, hypovitaminosis, and hypothermia.

Bacterial or viral bronchitis is transmitted by airborne droplets. The danger comes from those forms that are caused by pathogenic microorganisms that can survive for a long time in conditions environment. They attach to mucous membranes (many viruses, streptococci, staphylococci, pneumococci) and multiply there.

A vulnerable group for contracting the infection are the elderly, newborns and pregnant women, that is, those whose immunity is unstable.

Conditions for transmission of infection

Microorganisms with bronchitis can penetrate in different ways:

  • Through the air. This happens most often. When a patient coughs or sneezes, he releases hundreds of thousands of microbes that enter the external environment and penetrate the body of others.
  • By nutritional route. Infection occurs through food, saliva when using common hygiene items.
  • Autoinfection. In this case, microbes enter the body from its own foci of constant infection, for example, when chronic tonsillitis, sinusitis or carious teeth.

In addition to the penetration of infection, infection will require a decrease in general or local immunity, the influence low temperatures, poor nutrition and other factors.

How to recognize if a coughing person is dangerous

It is impossible to reliably determine this. In order to protect their child, young parents are trying to find out how good the health is in the constantly coughing grandmother, who strives to communicate with her grandson.

To do this, you can check a few things:

  1. Infectious bronchitis always manifests itself as inflammatory changes in the blood. He is accompanied by elevated temperature, cough with sputum, chest pain.
  2. To exclude pathogenic microflora in the mouth, which can pass to the child, you can take a smear or culture of sputum for flora and sensitivity.
  3. Check relatives and loved ones for allergies. These forms are not contagious, they are not transmitted to others.

To reliably confirm the etiology of the disease, consultation with a specialist and a number of additional studies will be required.

How to protect yourself from infection

Given the fact that infectious forms bronchitis can be contagious, the task of adults is to protect themselves and children when encountering patients and bacteria carriers.

To do this, it is important to understand that almost any sharp forms this disease can be contagious, exacerbations are also dangerous chronic types. However, during the period of remission they are less contagious. To protect yourself and your loved ones, you need to limit contact with sick people and avoid visiting crowded places during seasonal exacerbations of infectious diseases.

The incubation period of bacteria and viruses lasts from several hours to 2-3 days. At this time, the patient is already contagious, and clinical symptoms may be weakly expressed.

After clinical recovery, a person retains the ability to excrete bacteria for another 7-10 days. The task of adults is to limit children’s communication with him during this period.

To stimulate your own immunity, Dr. Komarovsky recommends maintaining optimal humidity and temperature in the room, and regularly moisturizing the mucous membrane of the upper respiratory tract. It has been scientifically proven that it is the disturbance of the microclimate in residential premises and the dryness of the mucous membranes that contribute to the attachment and proliferation of microbes.