"With a chest infection, you cough much more mucus up," agrees Coffey. "With a bacterial infection, this can be yellow, green, or a darker colour." If you cough up blood or rusty-coloured sputum, you should definitely see a doctor. "Patents may also experience chest pain, difficulty breathing or a rapid heart-rate."
Signs and symptoms of a chest infection
a persistent cough. coughing up yellow or green phlegm (thick mucus), or coughing up blood. breathlessness or rapid and shallow breathing. wheezing.
You might also cough up thick, yellow or green mucus. These symptoms may also occur with a cold. But if they last for more than a week or are severe, you may have a bacterial infection and need antibiotics. Only your doctor can prescribe antibiotics.
your cough is severe or lasts longer than 3 weeks. you have a high temperature for more than 3 days – this may be a sign of flu or a more serious condition, such as pneumonia.
Antibiotics aren't recommended for many chest infections, because they only work if the infection is caused by bacteria, rather than a virus. Your GP will usually only prescribe antibiotics if they think you have pneumonia, or you're at risk of complications such as fluid building up around the lungs (pleurisy).
If you have coronavirus (COVID-19), you can spread the virus to other people for up to 10 days from when your infection starts. But many people will no longer be contagious to others after 5 days.
The symptoms of viral and bacterial chest infections are similar but the colour of any mucus coughed up may indicate the cause; white or clear mucus usually indicates a viral infection whereas green or yellow mucus suggests that the infection is bacterial.
See a GP if:
you've had a cough for more than 3 weeks (persistent cough) your cough is very bad or quickly gets worse – for example, you have a hacking cough or cannot stop coughing. you feel very unwell. you have chest pain.
Warning signs
"With a viral cough, you often have a fever which tends to go up and down," explains Coffey. "With a bacterial infection, such as pneumonia, you tend to have a consistently high fever - usually around 38-40°C." If your fever remains persistently high, it's worth giving your GP a call.
Most of the time, a cough is acute, or temporary. Most acute coughs last around 3 weeks or less. Sometimes, a cough may last longer than 3 weeks, becoming subacute or chronic. This can be due to a postnasal drip, the effects of an infection, or an underlying health condition.
Many chest infections are caused by a virus. This usually clears up by itself after a few weeks and antibiotics won't help. Some chest infections are caused by bacteria. Your GP may prescribe antibiotics.
If you see green or yellow phlegm, it's usually a sign that your body is fighting an infection. The color comes from white blood cells. At first, you may notice yellow phlegm that then progresses into green phlegm. The change occurs with the severity and length of the potential sickness.
A bronchitis cough sounds like a rattle with a wheezing or whistling sound. As your condition progresses, you will first have a dry cough that can then progress towards coughing up white mucus.
After 2 or 3 days, mucus may change to a white, yellow, or green color. This is normal and does not mean you need an antibiotic. Some symptoms, especially runny or stuffy nose and cough, can last for up to 10 to 14 days.
Robinson thinks that if you are well enough to get up and about, you are probably well enough to go into work, while taking precautions to try to avoid spreading it. “You should stay at home if you have an illness that involves a fever, because that usually means it's still in its contagious form,” says Khan.
Amoxycillin, or alternatively erythromycin, will usually be suitable. In any patient, of any age, with a lower respiratory infection, the presence of new focal chest signs should be treated as pneumonia and antibiotic therapy should not be delayed.
If you have a bacterial chest infection, you should start to feel better 24 to 48 hours after starting on antibiotics. You may have a cough for days or weeks. For other types of chest infections, the recovery is more gradual. You may feel weak for some time and need a longer period of bed rest.
Although chest infections aren't generally as contagious as other common infections, like flu, you can pass them on to others through coughing and sneezing. Therefore, it's important to cover your mouth when you cough or sneeze and to wash your hands regularly.
If your pneumonia isn't treated, the pleura can get swollen, creating a sharp pain when you breathe in. If you don't treat the swelling, the area between the pleura may fill with fluid, which is called a pleural effusion. If the fluid gets infected, it leads to a problem called empyema.