What Are The Causes Of Pneumonia
Pneumonia is commonly caused by an infection with a germ. The germ is usually a bacterium or a virus. There are three or four different bacteria that are the most common causes of pneumonia. There is also a well-known group of bacteria that causes pneumonia in about 3 out of 10 cases. They are called atypicals. Other germs such as fungi, yeasts, or protozoa can sometimes also cause pneumonia.
Rarely, non-infective pneumonia is caused by inhaling poisons or chemicals. Many different substances can cause this. They can be in the form of liquids, gases, small particles, dust or fumes.
You may breathe in some bacteria, viruses, or other germs. If you are normally healthy, a small number of germs usually doesn’t matter. They will be trapped in your phlegm and killed by your immune system. Sometimes the germs multiply and cause lung infections. This is more likely to happen if you are already in poor health – for example:
- If you are frail or elderly.
- If you have a chest disease.
- If you have a low immunity to infection. Low immunity can be caused by such things as alcohol dependence, AIDS, or another serious illness.
However, even healthy people sometimes develop pneumonia.
Pneumonia can sometimes develop after an operation, particularly in the region of your head or neck. Having an anaesthetic can increase the risk.
How Do The Lungs Work
Your lungs main job is to get oxygen into your blood and remove carbon dioxide. This happens during breathing. You breathe 12 to 20 times per minute when you are not sick. When you breathe in, air travels down the back of your throat and passes through your voice box and into your windpipe . Your trachea splits into two air passages . One bronchial tube leads to the left lung, the other to the right lung. For the lungs to perform their best, the airways need to be open as you breathe in and out. Swelling and mucus can make it harder to move air through the airways, making it harder to breathe. This leads to shortness of breath, difficulty breathing and feeling more tired than normal.
Symptoms During The Gray Hepatization Phase
This is the more severe phase of lobar pneumonia, and while you may not notice as much coughing or sputum production, shortness of breath is common. Your alveoli are surrounded by swelling and fibrous strands that keep them from moving gases like oxygen in and out of your bloodstream.
Medical emergency
You might have symptoms of hypoxia as your gas exchange is impaired. This is a life threatening emergency. Call emergency services or go to the nearest emergency room if you experience:
- a blueish tinge to your lips or nail beds
- severe shortness of breath
- a rapid heartbeat
- shallow breathing
In this stage, supplemental oxygen or even mechanical ventilation may be required to prevent additional complications from hypoxia.
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When Would I Need To Be Hospitalized For Pneumonia
If your case of pneumonia is more severe, you may need tostay in the hospital for treatment. Hospital treatments may include:
- Oxygen
- Fluids, antibiotics and other medicines given through an IV
- Breathing treatments and exercises to help loosen mucus
People most likely to be hospitalized are those who are most frail and/or at increased risk, including:
- Babies and young children
- People with weakened immune systems
- People with health conditions that affect the heart and lungs
It may take six to eight weeks to return to a normal level of functioning and well-being if youve been hospitalized with pneumonia.
What Is Pneumonia Exactly

Pneumonia is an infection in the gas-exchanging units of the lung , says Michael Niederman, M.D., clinical director of pulmonary and critical care medicine at Weill Cornell Medical College in New York. Translation: the air sacs in your lungs become inflamed or even fill with fluid or pus, which interferes with your bodys ability to deliver oxygen to your blood.
About half the time, its due to bacteria, says Dr. Edelman. The other half the time, its due to viruses. The most common type of pneumonia is caused by the bacteria streptococcus pneumoniae, in the same family of bacteria that causes strep throat. Influenza is also a key virus that can spur pneumonia, and fungi can be a culprit, too. The novel coronavirus, of course, can also cause pneumonia, albeit one with a longer incubation period than, say, the flu, says Dr. Dasgupta.
Pneumonia develops if the organism overwhelms the patients host defenses, says Dr. Niederman. This basically means that a foreign bug takes over your immune system, even if youre generally healthy. Thats because certain organisms, like those associated with the flu, can be particularly hostile or invade your body in large numbers.
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Things You Should Know About Pneumonia
- By Stephanie Watson, Executive Editor, Harvard Women’s Health Watch
Pneumonia is an infection that causes the air sacs in the lungs to fill up with fluid or pus, which makes it harder to breathe. The most common symptoms are cough that may be dry or produce phlegm, fever, chills and fatigue. Other symptoms may include nausea, vomiting, diarrhea, and pain in the chest. and shortness of breath. Signs that indicate a more severe infection are shortness of breath, confusion, decreased urination and lightheadedness. In the U.S., pneumonia accounts for 1.3 visits to the Emergency Department, and 50,000 deaths annually.
With the COVID-19 pandemic continuing to affect people around the world, pneumonia has become an even larger health concern. Some people infected with the COVID-19 have no symptoms, while others may experience fever, body ache, dry cough, fatigue, chills, headache, sore throat, loss of appetite, and loss of smell.
The more severe symptoms of COV-19, such as high fever, severe cough, and shortness of breath, usually mean significant lung involvement. The lungs can be damaged by overwhelming COVID-19 viral infection, severe inflammation, and/or a secondary bacterial pneumonia. COVID-19 can lead to long lasting lung damage.
Here are other important facts you should know about pneumonia:,
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Medical History And Physical Exam
Your doctor will ask about your signs and symptoms and when they began. Your doctor will also ask whether you have any risk factors for pneumonia. Your doctor also may ask about:
- Exposure to sick people at home, school, or work or in a hospital
- Flu or pneumonia vaccinations
- Exposure to birds and other animals
- Smoking
During your physical exam, your doctor will check your temperature and listen to your lungs with a stethoscope.
Going To The Hospital
If you have severe pneumonia, you may have to go to the hospital:
- In most cases of pneumonia you get in your daily life, such as at school or work , it is not necessary to go to the hospital.footnote 2
- About one-third of people with community-based pneumonia are age 65 or older.footnote 2 Older adults are treated in the hospital more often and stay longer for the condition than younger people.footnote 2 Pneumonia is more serious in this group, because they often have and may develop other medical problems.
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Besides Vaccination What Else Can I Do To Prevent Bacterial And Viral Pneumonia
Receiving all recommended vaccinations is one of the best ways to prevent pneumonia. Additionally, there are several other ways to prevent pneumonia, including:
- Quitting smoking, and avoiding secondhand smoke. Smoking damages your lungs.
- Washing your hands before eating, before handling food, after using the restroom, and after being outside. If soap is not available, use an alcohol-based hand sanitizer.
- Avoiding being around people who are sick. Ask them to visit when they are feeling better.
- Not touching or sharing objects that are shared with others. Germs can be transferred from object to you if you touch your nose or mouth without washing or sanitizing your hands first.
- Eating a healthy diet, exercise, and get enough rest. Healthy habits keep your immune system strong.
- Getting treated for any other infections or health conditions you may have. These conditions could weaken your immune system, which could increase your chance of infections.
- Avoiding excessive consumption of alcohol.
Critical Role Of Pneumococcal Vaccine In Preventing Pneumonia
In children aged three months to four years, the most common type of bacterial pneumonia is Strep. pneumoniae. In children greater than age four, it remains in the top three most common types. The pneumococcal vaccine series, started at two months of age, significantly reduces the rates of bacterial pneumonia from Strep. Pneumoniae. The vaccine is usually administered during wellness or prevention visits and cannot be given to a child with a fever. This emphasizes the need for healthcare access globally.6
With global vaccination rates currently plateauing, the challenges of diagnosing and treating community acquired pneumonia are even more pertinent for prevention of severe respiratory illness. Vaccine uptake challenges can be overcome with global measures to increase the access and use of vaccines. Addressing vaccine use and providing education about common pneumonia symptoms can aid in early diagnosis of pneumonia and lower the rate of severe respiratory illness and prolonged hospitalization.
References
World Health Organization Health Topics. Immunization, Vaccines and Biologicals: National programs and systems on improving vaccination demand and addressing hesitancy. 17 June 2020 update.
Popovsky EY, Florin TA. Community-Acquired Pneumonia in Childhood. Reference Module in Biomedical Sciences. 2020 B978-0-08-102723-3.00013-5. doi:10.1016/B978-0-08-102723-3.00013-5
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How Does Pneumonia Lead To Death
The most common complication from pneumonia is a condition called pleural effusion. This is the buildup of fluid in the membranes around the lungs inside the chest cavity. It causes pain and impairs your ability to breathe. These and other complications of pneumonia can lead to a worsening of pre-existing heart and lung conditions.
Who Is Most At Risk For Getting Pneumonia

People who have an increased risk of pneumonia include:
- People over the age of 65 and infants under age 2. The weakening immune system of older people makes them less able to fight off illnesses. Similarly, the immune system of infants is still developing and not at full-strength, making them more susceptible to infection.
- People with a health-caused weakened immune system. Examples include:
- People who are receiving chemotherapy
- Transplanted organ recipients
- People who have HIV/AIDS
- People with autoimmune disease and who are taking medications that suppress the immune system.
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Spreading Pneumonia To Others
If your pneumonia is caused by a virus or bacteria, you may spread the infection to other people while you are contagious. How long you are contagious depends on what is causing the pneumonia and whether you get treatment. You may be contagious for several days to a week.
If you get antibiotics, you usually cannot spread the infection to others after a day of treatment.
What Increases Your Risk
You are more likely to get pneumonia if you:
- Smoke. Cigarette smoking is a strong risk factor for pneumonia in healthy young people.
- Have another medical condition, especially lung diseases such as chronic obstructive pulmonary disease or asthma.
- Are younger than 1 year of age or older than 65.
- Have an impaired immune system.
- Take medicine called a proton pump inhibitor that reduces the amount of stomach acid.footnote 3, footnote 4
- Drink excessive amounts of alcohol.
- Recently had a cold or the flu.
You are more likely to have complications of pneumonia and need to go to the hospital if you:
- Are older than 65.
- Have some other illness , or have gone to the hospital for a medical problem within the last 3 months.
- Have had your spleen removed or do not have a working spleen .
- Have an alcohol use problem.
- Have a weak immune system.
- Reside in a place where people live close together, such as a university dorm or nursing home.
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Viral Vs Bacterial Pneumonia Symptoms
Although viral and bacterial pneumonia symptoms can be very similar, there are some key differences between the two. The section below outlines some examples.
- Lungs affected: Bacterial pneumonia tends to affect one particular part, or lobe, of a lung, whereas viral pneumonia typically affects both lungs.
- Symptom onset: The symptoms of bacterial pneumonia can develop either suddenly or gradually, whereas symptoms of viral pneumonia typically develop over several days.
- Symptoms: People with bacterial pneumonia usually experience a higher temperature and a wet cough, whereas people with viral pneumonia
How Soon After Treatment For Pneumonia Will I Begin To Feel Better
How soon you will feel better depends on several factors, including:
- Your age
- The cause of your pneumonia
- The severity of your pneumonia
- If you have other at-risk conditions
If you are generally healthy, most symptoms of bacterial pneumonia usually begin to improve within 24 to 48 hours after starting treatment. Symptoms of viral pneumonia usually begin to improve within a few days after starting treatment. A cough can last for several weeks. Most people report being tired for about a month after contracting pneumonia.
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When Should You Call Your Doctor
The faster you get treatment, the faster you will get over pneumonia. This is especially true for the very young, for people older than 65, and for anyone with other long-lasting health problems, such as asthma.
911 or other emergency services immediately if you:
- Have chest pain that is crushing or squeezing, is increasing in intensity, or occurs with any other symptoms of a heart attack.
- Have such bad trouble breathing that you are worried you will not have the strength or ability to keep breathing.
- Cough up large amounts of blood.
- Feel that you may faint when you sit up or stand.
if you have:
- A cough that produces blood-tinged or rust-coloured mucus from the lungs.
- A fever with shaking chills.
- Difficult, shallow, fast breathing with shortness of breath or wheezing.
- Frequently brings up yellow or green mucus from the lungs and lasts longer than 2 days. Do not confuse mucus from your lungs with mucus running down the back of your throat from your nasal passages . Post-nasal drainage is not a worry.
- Occurs with a fever of 38.3°C or higher and brings up yellow or green mucus from the lungs .
- Causes you to vomit a lot.
- Continues longer than 4 weeks.
Also call your doctor if you have new chest pain that gets worse with deep breathing and if you have other symptoms of pneumonia, such as shortness of breath, cough, and fever.
How Can I Help Myself Feel Better
If your doctor has prescribed medicine, follow the directions carefully.
You may feel better in a room with a humidifier, which increases the moisture in the air and soothes irritated lungs. Make sure you drink plenty of fluids, especially if you have a fever. If you have a fever and feel uncomfortable, ask the doctor whether you can take over-the-counter medicine such as acetaminophen or ibuprofen to bring it down. But don’t take any medicine without checking first with your doctor a cough suppressant, for example, may not allow your lungs to clear themselves of mucus.
And finally, be sure to rest. This is a good time to sleep, watch TV, read, and lay low. If you treat your body right, it will repair itself and you’ll be back to normal in no time.
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Is Pneumonia Contagious
Certain types of pneumonia are contagious . Pneumonia caused by bacteria or viruses can be contagious when the disease-carrying organisms are breathed into your lungs. However, not everyone who is exposed to the germs that cause pneumonia will develop it.
Pneumonia caused by fungi are not contagious. The fungi are in soil, which becomes airborne and inhaled, but it is not spread from person to person.
What Is Pneumonia

Pneumonia is an infection of the lungs that may be caused by bacteria, viruses, or fungi. The infection causes the lungs’ air sacs to become inflamed and fill up with fluid or pus. That can make it hard for the oxygen you breathe in to get into your bloodstream. The symptoms of pneumonia can range from mild to severe, and include cough, fever, chills, and trouble breathing.
Many factors affect how serious a case of pneumonia is, such as the type of germ causing the lung infection, the persons age, and their overall health. The people most at risk are infants and young children, adults 65 or older, and people who have other health problems.
Pneumonia is a leading cause of hospitalization in both children and adults. Most cases can be treated successfully, although it can take weeks to fully recover. Tens of thousands of people in the U.S. die from pneumonia every year, most of them adults over the age of 65.
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