Is Pneumonia Contagious

Pneumonia is the name we give to the lung infection. To be more precise, pneumonia is the infection of the lung tissues and alveoli. In this text we will explain how “acquired” pneumonia, what are your symptoms, how a diagnosis is made and what is the right treatment.

What are alveoli?

Read the text and see the picture below to better understand the explanations (click to enlarge). The air we breathe in through the nose / mouth and goes into the trachea, this, to reach the level of the lungs, splits and forms the main bronchi, one for the left, another to the right, these bronchi also forking , forming the bronchioles, which finally end in the alveoli. Whenever it happens a fork, the structures are becoming progressively smaller.

Alveoli are microscopic cavities are left in contact with the blood. Through these changes are made of respiratory gases (oxygen and carbon dioxide). The socket is in the inspired oxygen reaches the erythrocytes (red blood cells).

In pneumonia, the alveoli, which should have little air is full of purulent secretions (with pus), preventing its operation. These alveoli no gas exchange.

The more alveoli undertaken, pneumonia is more extensive and more severe the box.

How do you get pneumonia?

Actually, “purchase” is not the most appropriate term, because it gives the idea of ​​disease transmission between individuals. Pneumonia is not a contagious disease like the flu or tuberculosis.

Pneumonia can be caused, in decreasing order of frequency, by bacteria, viruses, fungi and parasites.

Our lung is constantly exposed to microbes from the air and from our own bacterial flora of the mouth. We are not sick all the time because the lung has its own defense mechanisms, including the cough reflex, immune system cells and microscopic cilia in the bronchial tree to “sweep” the invaders out of the airways.

The development of pneumonia depends on the virulence of the invader, the amount of germs that get into the lungs and the patient’s immunological conditions.

A serious type of pneumonia is aspiration pneumonia. It occurs in people who vomit and then aim their content. Imagine a patient with reduced awareness that loses the ability to cough or to swallow his own saliva, causing fluid from the oral cavity fall into the airways. The air of this person is exposed to a huge amount of microbes, encouraging the development of pneumonia. A common example is someone who drank a lot and is in a coma or pre-coma alcoholic.

Patients who smoke have a constant irritation around the bronchial tree and protective cilia dysfunction. Lung defense cells are also affected by smoking and not work as well. All this favors the appearance of respiratory infections.

The main risk factors for pneumonia are:

Age over 65 years.
Viral respiratory infections, such as influenza.
Immunological diseases (HIV, transplant, cancer …).
COPD (chronic obstructive pulmonary disease, chronic bronchitis and emphysema).
Drug users.
Sick in bed.
Patients with reduced level of consciousness.
Prolonged hospitalization.
Patients on mechanical ventilation.
Patients with another previous lung disease.

Symptoms of pneumonia

The signs and symptoms of patients with pneumonia include coughing, fever, chills, shortness of breath, chest pain when breathing deeply, vomiting, loss of appetite, exhaustion and body aches. There may be presence of mixed blood in the sputum. Fever pneumonia is characteristically high.

One of the possible complications of pneumonia is the formation of pleural effusion.

Patients may have lived an atypical, with little cough and no fever. Sometimes pneumonia in this group is presented only with prostration and mental disorders, such as disorientation and mental confusion.

In extensive pneumonia, when much of the lung tissue is affected, the patient may go into respiratory failure, requiring tracheal intubation, mechanical ventilation and hospitalization in intensive care unit (ICU).

Pneumonia x tuberculosis

Many patients presenting with symptoms of cough and sputum are frightened by the possibility of having tuberculosis. The difference is in the time of disease progression. Pneumonia develops in hours and the patient becomes ill soon after the disease. In 24-48 hours the patient seeks medical attention. Tuberculosis is presented as a more driven, with gradually worsening symptoms and the patient often seek medical attention only several weeks after the onset of symptoms.

For more information on tuberculosis, read: TUBERCULOSIS | Symptoms and treatment

Diagnosis of pneumonia

The diagnosis of pneumonia is usually made by physical examination and chest radiography. Blood tests can help but are not essential. A good doctor is able to diagnose pneumonia just with the medical history and physical examination.


Radiography, as a cheap and widely available test, is usually required to confirm the diagnosis. The alveoli filled with secretion appear as a white spot on the chest radiograph, as seen in the photo below.

The hemogram of pneumonia patient presents a large increase in the number of leukocytes, typical of bacterial infections (read: CBC | normal values).

In the most severe patients who need hospitalization, usually try to identify what is the bacteria responsible for pneumonia. We investigate the bacteria in the blood (via blood culture) or at the patient’s sputum. In selected cases may require collection lung secretions directly through bronchoscopy.

Treatment of Pneumocystis

Pneumonias are divided into community, when they are acquired daily, and hospital, as they arise in hospitalized patients. Nosocomial pneumonia is more severe and more difficult to treat, as it is usually caused by bacteria more resistant and affects most fragile patients.

The treatment of bacterial pneumonia is carried out with antibiotics for at least eight days. The community pneumonia can be treated with oral antibiotics, however, those that evolve bad need of hospitalization and intravenous antibiotics.

The main drugs used for community pneumonia are amoxicillin, azithromycin, clarithromycin, ceftriaxone, levofloxacin and moxifloxacin. Expected signs of improvement from the third day of treatment.

Pneumonia can easily produce a sepsis and are often major causes of death in elderly or immunocompromised.

Since no vaccine against streptococcal pneumonia, caused by Streptococcus pneumoniae, the most common type. It is suitable for children and people over age 50, however does not prevent pneumonia caused by other germs.

Does getting cold causes pneumonia?

The Legend of cold is widespread in the population, but has only a small piece of truth. As I explained, it is necessary to have pneumonia bacterial infection, not just a stream of cold air to infect.

What happens is that in the cold, the defense system, mainly the cilia of the airways, work more slowly, which favors the invasion of germs. During the winter, the people walking on the street and less agglomeration indoors, favoring the transmission of viruses such as influenza. Viral respiratory infections are risk factors, particularly in the elderly, which can lead to the onset of pneumonia.

Thus acquired pneumonia because nobody opened the refrigerator with wet body or because she took a shower leaving work or school. Happily, our immune system is strong enough to deal with trivial situations how are you.

Share on TwitterShare on TumblrSubmit to StumbleUponSave on DeliciousDigg ThisSubmit to redditShare on Myspace