Pneumonia is a form of acute respiratory infection that affects the lungs. The lungs are made up of small sacs called alveoli, which fill with air when a healthy person breathes. When an individual has pneumonia, the alveoli are filled with pus and fluid, which makes breathing painful and limits oxygen intake.
Pneumonia is still a common disease affecting around 1 per cent of the adult population each year. Many people die from it every year, most commonly women and especially people over the age of 70. The overall death rate due to pneumonia is currently 5 per cent, ie around 1 in 20 people contracting the condition die from it.Half of all pneumonia cases are caused by bacteria. The bacteria, known as streptococcus pneumoniae is the main cause of the most typical pneumonia.
There are different causes of pneumonia:
- By breathing: The tiny droplets get into the air when a person infected with these germs coughs or sneezes. The other person can get these germs by breathing in infected air.
- Pneumonia is caused when bacteria or viruses that are normally present in the mouth, throat, or nose inadvertently enter the lung. A healthy person's nose and throat often contain bacteria or viruses that cause pneumonia.
- People with recent viral infections, lung disease, heart disease, and swallowing problems can easily get germs of pneumonia
- Alcoholics, drug users, and those who have suffered a stroke or seizure are at higher risk for developing pneumonia than the general population.
Once organisms enter the lungs, they usually settle in the air sacs of the lung where they rapidly grow in number.This area of the lung then becomes filled with fluid and pus as the body attempts to fight off the infection
Pneumonia can affect people of all ages. However, two age groups are at greater risk of developing pneumonia:
- Infants who are 2 years old or younger (because their immune systems are still developing during the first few years of life)
- People who are 65 years old or older
Other conditions and factors also raise your risk for pneumonia. You're more likely to get pneumonia if you have a lung disease or other serious disease. Examples include cystic fibrosis, asthma, COPD (chronic obstructive pulmonary disease),bronchiectasis, diabetes, heart failure, and sickle cell anemia.
You're at greater risk for pneumonia if you're in a hospital intensive-care unit, especially if you're on a ventilator (a machine that helps you breathe).
Having a weak or suppressed immune system also raises your risk for pneumonia. A weak immune system may be the result of a disease such as HIV/AIDS. A suppressed immune system may be due to an organ transplant or blood and marrow stem cell transplant, chemotherapy (a treatment for cancer), or long-term steroid use.
Your risk for pneumonia also increases if you have trouble coughing because of a stroke or problems swallowing. You're also at higher risk if you can't move around much or are sedated (given medicine to make you relaxed or sleepy).
Smoking cigarettes, abusing alcohol, or being undernourished also raises your risk for pneumonia. Your risk also goes up if you've recently had a cold or the flu, or if you're exposed to certain chemicals, pollutants, or toxic fumes.
Pneumonia often mimics the flu, beginning with a cough and a fever, so you may not realize you have a more serious condition. Symptoms can vary depending on your age and general health.
The signs and symptoms of pneumonia may include:
- Lower-than-normal body temperature in older people
- Shortness of breath
- Shaking chills
- Chest pain that fluctuates with breathing (pleurisy)
- Muscle pain
Pneumonia is usually diagnosed based on symptoms and physical examination alone. Diagnosing pneumonia can be difficult in some people, especially those who have other illnesses.An important test for pneumonia in unclear situations is a chest x-ray. Chest x-rays can reveal areas of opacity (seen as white) which represent consolidation. Pneumonia is not always seen on x-rays, either because the disease is only in its initial stages, or because it involves a part of the lung not easily seen by x-ray. In some cases, chest CT (computed tomography) can reveal pneumonia that is not seen on chest x-ray. X-rays can be misleading, because other problems, like lung scarring and congestive heart failure, can mimic pneumonia on x-ray. Chest x-rays are also used to evaluate for complications of pneumonia.
If the doctor has concerns about the diagnosis, a culture of the person's sputum may be requested. Sputum cultures generally take at least two to three days, so they are mainly used to confirm that the infection is sensitive to an antibiotic that has already been started. A blood sample may similarly be cultured to look for bacteria in the blood. Any bacteria identified are then tested to see which antibiotics will be most effective.
You may continue to cough for two to three weeks after finishing your course of antibiotics and feel tired even longer, as your body continues to recover.
Let your doctor know if your symptoms do not begin to get better within two days of starting treatment. Your symptoms may not have improved because:
- the bacteria causing the infection may be resistant to antibiotics - your doctor may change to a different antibiotic, or may start treatment with a second antibiotic while you continue to take the first one
- a virus may be causing the infection, rather than bacteria - antibiotics have no effect on viruses and your body's immune system will have to fight the viral infection by creating antibodies to it
You may need hospital treatment if your symptoms are severe. This includes antibiotics and fluids given intravenously through a drip, or oxygen to help breathing.
In very serious cases of pneumonia, breathing may need to be assisted through a ventilator in an intensive care unit (ICU).
Your doctor will probably ask to see you again around six weeks after you started your antibiotics.
In some cases, they may arrange follow-up tests such as a chest X-ray, for example if:
- your symptoms have not improved
- your symptoms have come back
- you smoke
- you are over the age of 50
If not treated properly, pneumonia can cause acute respiratory distress syndrome, lung abscesses (pus-filled cavities in the lung), bacteria in the blood, a collapsed lung, hemoptysis (coughing up blood), and death.
You can take painkillers such as paracetamol or ibuprofen to relieve pain and reduce fever. You should not take ibuprofen if you:
- are allergic to aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs)
- have asthma, kidney disease, a history of stomach ulcers or indigestion
Cough medicines are not recommended. Coughing enables you to clear mucus from your lungs, so trying to stop your cough could make the infection last longer. Also, there is little evidence cough medicines are effective. A warm drink of honey and lemon can help relieve the discomfort caused by coughing.
Drink plenty of fluids to avoid dehydration and get plenty of rest to help your body recover.
If you smoke, it is more important than ever to stop as smoking damages your lungs.
Pneumonia is not usually passed from one person to another so it is safe to be with others, including family members. However, it would be sensible for those with weakened immune systems to avoid a person with pneumonia until they are starting to get better.
Some people may be advised to have vaccinations against flu or pneumococcal infections after recovering from pneumonia.