Pneumonia/Pneumonia plus Control
What is pneumonia?
Pneumonia is an infection in one or both lungs caused by bacteria, viruses, or fungi. The infection leads to inflammation of the air sacs in the lungs, which are called alveoli. The alveoli fill with fluid or pus, making it difficult to breathe. Both viral and bacterial pneumonia is contagious. This means they can spread from person to person through inhalation of airborne droplets from a sneeze or cough.
You can also get these types of pneumonia by coming in contact with surfaces or objects that are contaminated with bacteria or viruses that cause pneumonia. You can get fungal pneumonia from the environment. It is not transmitted from person to person. Pneumonia is further classified according to where or how it was acquired:
- Hospital-acquired pneumonia (HAP). This type of bacterial pneumonia is acquired during a hospital stay. It can be more serious than other types since the bacteria involved can be more resistant to antibiotics.
- Community-acquired pneumonia (CAP). This refers to pneumonia that is acquired outside of a medical or institutional setting.
- Ventilator-associated pneumonia (VAP). When people using a ventilator get pneumonia, it’s called VAP.
- Aspiration pneumonia. Inhalation of bacteria into the lungs through food, drink, or saliva can cause aspiration pneumonia. It is more likely to occur if you have trouble swallowing or are overly sedated from the use of medication, alcohol, or other drugs.
Walking pneumonia is a milder case of pneumonia. People with walking pneumonia may not even know they have pneumonia. Your symptoms may look more like a mild respiratory infection than pneumonia. However, walking pneumonia may require a longer recovery period. Symptoms of walking pneumonia can include things like:
- slight fever
- dry cough that lasts more than a week
- shaking chills
- difficulty breathing
- Chest pain
- reduced appetite
Viruses and bacteria, such as Streptococcus pneumoniae or Haemophilus influenzae, often cause pneumonia. However, in walking pneumonia, the bacterium Mycoplasma pneumonia is the most common cause of the condition.
Pneumonia can be classified based on the area of the lungs it affects:
Bronchopneumonia can affect areas in both lungs. It is often located near or around the bronchi. These are the tubes that run from the trachea to the lungs.
2. Lobar pneumonia
Lobar pneumonia affects one or more lobes of the lungs. Each lung is made of lobes, which are defined sections of the lung. Lobar pneumonia can be divided into four stages based on its progress:
- Congestion. Lung tissue appears heavy and congested. Fluid-filled with infectious organisms has accumulated in the alveoli.
- Red hepatization. Red blood cells and immune cells have entered the fluid. This causes the lungs to appear red and solid in appearance.
- Gray hepatization. The red blood cells have started to break down while the immune cells remain. The breakdown of red blood cells causes a change in colour, from red to grey.
- Resolution. Immune cells have begun to clear the infection. A productive cough helps expel the remaining fluid from the lungs.
The symptoms of pneumonia can be mild or life-threatening. They may include:
- cough that may produce phlegm (mucus)
- sweating or chills
- shortness of breath that occurs while doing normal activities, or even while resting
- chest pain that gets worse when breathing or coughing
- feeling tired or fatigued
- loss of appetite
- nausea or vomiting
Other symptoms may vary according to your age and general state of health:
- Babies may seem to have no symptoms, but sometimes they may vomit, lack energy, or have trouble drinking or eating.
- Children under 5 years of age may have rapid breathing or wheezing.
- Older adults may have milder symptoms. They may also experience confusion or a lower-than-normal body temperature.
Pneumonia occurs when germs enter the lungs and cause an infection. The immune system’s reaction to clear the infection causes inflammation of the air sacs of the lungs (alveoli). This inflammation can eventually cause the air sacs to fill with pus and fluid, leading to symptoms of pneumonia. Several types of infectious agents can cause pneumonia, including bacteria, viruses, and fungi.
1. Bacterial pneumonia
The most common cause of bacterial pneumonia is Streptococcus pneumonia. Other causes include:
- mycoplasma pneumonia
- Haemophilus influenzae
- Legionella pneumophila
2. Viral pneumonia
Respiratory viruses are often the cause of pneumonia. Examples of viral infections that can cause pneumonia include:
- influenza (flu)
- respiratory syncytial virus (RSV)
- rhinovirus (common cold)
- human parainfluenza virus (HPIV) infection
- human metapneumovirus (HMPV) infection
- chickenpox (varicella-zoster virus)
- adenovirus infection
- coronavirus infection
- SARS-CoV-2 infection (the virus that causes COVID-19)
Although the symptoms of viral and bacterial pneumonia are very similar, viral pneumonia is usually milder. It may get better in 1 to 3 weeks without treatment. According to the National Heart, Lung, and Blood Institute, people with viral pneumonia are at risk of developing bacterial pneumonia.
3. Fungal pneumonia
Fungi in the soil or in bird droppings can cause pneumonia. They most often cause pneumonia in people with weakened immune systems. Examples of fungi that can cause pneumonia include:
- Pneumocystis jirovecii
- cryptococcus species
- histoplasmosis species
Your doctor will begin by taking your medical history. You will be asked questions about when your symptoms first appeared and about your general health. Then they will do a physical exam. This will include listening to your lungs with a stethoscope for any abnormal sounds, such as a pop. Depending on the severity of your symptoms and your risk of complications, your doctor may also order one or more of these tests:
- Chest x-ray
An x-ray helps your doctor look for signs of swelling in your chest. If there is inflammation, the x-ray can also tell your doctor about its location and extent.
- Blood culture
This test uses a blood sample to confirm an infection. The culture can also help identify what may be causing your condition.
- Sputum culture
During a sputum culture, a sample of mucus is collected after you cough deeply. It is then sent to a laboratory to be analyzed to identify the cause of the infection.
- Pulse oximetry
Pulse oximetry measures the amount of oxygen in the blood. A sensor placed on one of your fingers can tell if your lungs are moving enough oxygen through your bloodstream.
- Computed tomography
CT scans provide a clearer, more detailed picture of your lungs.
- Fluid sample
If your doctor suspects there is fluid in the pleural space of your chest, he or she may take a sample of the fluid with a needle placed between your ribs. This test can help identify the cause of your infection.
A bronchoscopy examines the airways in your lungs. It does this by using a camera at the end of a flexible tube that is gently guided down the throat and into the lungs. Your doctor may perform this test if your initial symptoms are severe or if you are hospitalized and do not respond well to antibiotics.
Your treatment will depend on the type of pneumonia you have, how severe it is, and your overall health.
Your doctor may prescribe medicine to help treat your pneumonia. What you are prescribed will depend on the specific cause of your pneumonia. Oral antibiotics can treat most cases of bacterial pneumonia. Always take the entire course of antibiotics, even if you start to feel better. Not doing so may prevent the infection from clearing up and may be more difficult to treat in the future.
Antibiotic medicines do not work on viruses. In some cases, your doctor may prescribe an antiviral. However, many cases of viral pneumonia go away on their own with home care. Antifungal medications are used to treat fungal pneumonia. You may need to take this medication for several weeks to clear up the infection.