Bronchitis and pneumonia are two lung infections with similar symptoms. In some cases, bronchitis can turn into pneumonia. This occurs when an infection spreads from the airways to the air sacs in the lungs.
It is also possible for a person with bronchitis to develop a separate pneumonia infection. It can be difficult to tell the difference between bronchitis and pneumonia because the two infections have similar symptoms.
People most at risk are babies, older adults, and people with a weakened immune system or underlying health condition. Treating bronchitis quickly can help prevent it from developing into pneumonia.
Bronchitis is a lung infection that causes irritation and swelling in the airways. These effects prompt the lungs to make more mucus than normal, triggering a cough as the body tries to get rid of excess mucus.
The most common form of bronchitis is acute bronchitis, or a chest cold. Symptoms can include:
People usually recover from acute bronchitis within 3 weeks, once the infection clears up.
A person with an underlying health condition may find it harder to get over bronchitis, which can put them at higher risk for pneumonia. It is important to treat bronchitis quickly to stop the infection from spreading deeper into the lungs.
Pneumonia causes symptoms similar to those of bronchitis, as well as:
- rapid heartbeat
- loss of appetite
In some cases, rather than the infection spreading, a person will get a separate pneumonia infection alongside bronchitis.
Both infections have very similar symptoms, and this can make it difficult for doctors to provide an accurate diagnosis. A lung infection that they initially diagnosed as bronchitis may have been pneumonia from the start.
A less common form of bronchitis is chronic bronchitis. The symptoms are the same, but they can last for months. Chronic bronchitis is a recurring infection that appears for at least 2 consecutive years.
Chronic bronchitis is a lung condition that occurs when a person breathes in irritants over an extended period. These irritants damage the lungs and cause lasting swelling of the airways. The most common causes are smoking, air pollution, and chemicals in the workplace.
A person who has chronic bronchitis has lungs that function less effectively than normal. This impairment can make it harder for the body to fight off infection and increase the person’s risk for pneumonia.
In most cases, a virus causes bronchitis, and bacteria cause pneumonia.
The bacterium that most commonly causes pneumonia is Streptococcus pneumoniae. It can spread through coughing but is much less contagious than a cold or bronchitis. Most people’s immune system will kill the bacteria straight away.
A person can get pneumonia if their immune system is not working as well as usual. This dysfunction may be because of a recent illness or an underlying health condition. Someone who has bronchitis can be at a higher risk of developing pneumonia.
Other causes of pneumonia are less common bacteria, a virus, or fungi. If a less common bacterium causes pneumonia, doctors call the condition atypical pneumonia. This term refers to the fact that the symptoms appear slightly different than those of typical pneumonia.
It is less common for bacteria to cause bronchitis. When they do, there may be a higher risk of bronchitis turning into pneumonia because bacteria can multiply and spread quickly. The infection can spread from the airways to the air sacs in the lungs.
If a person has an underlying health condition or does not treat bronchitis quickly, the risk of developing pneumonia is higher.
Those who have a higher risk for pneumonia include:
- older adults
- babies and young children
- people who smoke
- people with a weakened immune system
- people with an underlying health condition, such as asthma
Specific forms of pneumonia have an association with being in a hospital. People who are in intensive care or using breathing apparatus have a higher risk.
Treating bronchitis quickly can help prevent pneumonia. Once the immune system has returned to working normally, the risk of developing a new infection falls.
People can also reduce their risk by quitting smoking to improve their lung health and wearing a face mask if they are using chemicals in the workplace. Regular exercise that raises the heart rate can help strengthen the lungs.
Ways to prevent the spread of pneumonia include washing the hands, covering the mouth when coughing or sneezing, and throwing tissues away straight after using them.
Older adults can consider getting the pneumonia vaccine to protect them from the illness. The Centers for Disease Control and Prevention (CDC) recommend that children under 2 years of age and adults aged 65 and over get the vaccine.
Diagnosis can be difficult, as bronchitis and pneumonia have very similar symptoms. It may not be possible to tell whether a person:
- has ongoing bronchitis
- has bronchitis that has turned into pneumonia
- had pneumonia from the start
A doctor will usually ask about medical history and do a physical examination. They will listen to the lungs for a crackling or bubbling sound.
If bronchitis becomes pneumonia, a person’s symptoms usually worsen. They will have a cough with mucus and a fever. If a doctor cannot diagnose pneumonia based on the person’s symptoms, they may suggest a chest X-ray or blood test.
Most people will be able to treat a case of acute bronchitis at home. They can rest, drink plenty of fluids, and take pain relief if necessary. A humidifier can make it easier to breathe by loosening mucus in the lungs. Honey or lozenges can ease symptoms for adults.
Doctors rarely prescribe antibiotics to treat bronchitis. These drugs treat bacterial infections, and bronchitis is almost always a viral infection.
It is usually possible to treat mild pneumonia at home, but it is advisable to seek medical advice. A doctor will usually prescribe antibiotics. People should always complete the full course of antibiotics, even once their symptoms have gone.
In more serious cases, a person may need to go to the hospital. Medical staff can check whether the treatment is working, give medication, and supply oxygen if necessary. If a person is too unwell to take tablets or drink fluids, they may need a drip.
Severe or persistent symptoms can indicate a more serious case. It is important to see a doctor if:
- a cough lasts longer than 2 weeks
- a person has a high temperature for 2 days in a row
- mucus contains blood
- shortness of breath gets worse
A person should seek medical advice if they get bronchitis and have an underlying health condition. Prompt treatment can lower the risk of pneumonia developing.
Pneumonia is the most common complication of bronchitis. It is more likely to affect people with a weakened immune system. Therefore, those who are unwell, have had a recent illness, or have an underlying health condition are at a higher risk. The condition is also more likely to affect babies and older adults.
Most people should be able to recover from bronchitis and mild pneumonia at home. Plenty of rest is important. Pneumonia can be serious, so a person should seek medical advice if they have symptoms.