With the average adult suffering an estimated 2-5 colds per year, and children around 10, most of us are no stranger to runny noses, coughs and sneezes. A bit of rest, plenty of fluids, taking paracetamol and perhaps a little honey and lemon are usually all it takes to see off a cold - without a visit to the GP.
But if a cough lingers for longer than usual, or we feel particularly unwell, we may start to wonder if we've developed a chest infection. Unlike colds, chest infections may need additional treatment, including antibiotics in the case of bacterial infections such as pneumonia.
So, what symptoms should we look out for?
I've been coughing for weeks
Whilst a persistent cough can be troublesome, having symptoms that last over two weeks - and even coughing up mucus - does not necessarily indicate a problem. "Viral coughs can last up to three weeks," explains GP Dr Julie Coffey.
"Many people think if you cough up a little bit of mucus you've got an infection, but this is not necessarily the case," explains Coffey. "But during a common cold the larger tubes in the airways become inflamed, and they produce more mucus than normal. Coughing up mucus that is clear, yellow or even green can be a normal part of a viral cough."
If you are coughing up more mucus than you have with previous coughs, or are suffering chest pain as a result of persistent coughing, it may be time to see your GP.
"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."
I have a fever
Feeling hot? Having a fever can be a normal part of having a cold and is not necessarily a sign of an infection. However, if you're working up a sweat, it's definitely worth taking and recording your temperature regularly.
"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.
I feel terrible!
Common colds can vary in their severity; whilst sometimes we can struggle on, a bad dose might see us stretched out on the sofa for a couple of days. If we feel particularly bad, we may start to worry that something is wrong.
"Of course, you will feel unwell with a cold - but not seriously unwell. If you have a chest infection, you'll feel significantly worse than you have in the past," explains Coffey.
"Patients who come to see me with an infection often know there's something wrong with them, as they feel much worse than they have with previous coughs and colds."
As well as feeling dreadful, patients with chest infection can feel "a bit drowsy, almost confused in their thinking," explains Coffey. "These symptoms would set alarm bells ringing."
I look dreadful!
A red nose, cold sores, chapped lips and a pale complexion often accompany a cold - and nobody looks their best when they've been up all night coughing. So can looking ill really be a sign that we need to see our GP?
"Doctors can often tell when a patient has pneumonia when they see you in the waiting room," explains Coffey. "You tend to look more unwell than you have before - the difference is often quite stark. Those around you will also be able to see how unwell you are."
"If you have a bluish tinge to your lips or extremities, this can also be a concern."
I'm in pain
Coughs and colds are often accompanied by headaches, sore throats and feelings of general malaise. "With a cold, or a flu-like illness, you can experience muscle aches," explains Dr Kenny Livingstone, GP and founder of ZoomDoc. "These can usually be managed with paracetamol."
However, pain can also be a sign that we’ve developed a chest infection, so how can we tell the difference?
"Although we suffer aches and pains as part of a cold, if the pain is severe or you are out of breath, this may be a sign that something is wrong," explains Coffey.
"Patients with a chest infection will often present with chest pain," says Livingstone. "This can also be accompanied by a feeling of 'tightness' or shortness of breath."
Am I at risk?
Whilst coughs and colds abound, particularly during the winter months, the chances of a fit and healthy person contracting a chest infection are minimal. "Generally, if you are a reasonably healthy person with no pre-existing problems, the chances are it will be a normal cough. For these, you don't need to visit your doctor or take antibiotics," says Coffey.
However, there are certain groups who are at greater risk. "If you have a weakened immune system, are very young, elderly or seriously overweight, you have an increased risk of pneumonia," explains Coffey. People with long-term lung conditions, including chronic obstructive pulmonary disease (COPD), asthma and bronchiectasis, are at particular risk of problems.
Those who have compromised immunity should take up the offer of a flu vaccine, to reduce their risk of infection. "A chest infection often starts with a flu-like illness," explains Livingstone. "The flu vaccine targets the most likely virus strain. So, if you reduce your risk of getting flu, you'll reduce your risk of a chest infection."
"If you're pregnant, or in an at-risk group, it's a good idea to have the vaccine."
I think I have a chest infection - what should I do?
Coffey recommends that the first port of call should always be your GP, even when symptoms are severe. "I'd always try the GP in the first instance," she says. "If you explain the symptoms fully to a receptionist, you should get through fairly quickly."
"Even if hospitalisation is needed, your GP will be able to help to get you seen more speedily on arrival."
Depending on the type and severity of your chest infection, and your overall general health, your GP will often prescribe antibiotics. "In the case of a bacterial infection, we'd usually give 5-7 days of antibiotics for a patient who was previously fit and well," explains Coffey. "Someone with lung disease might be given 10-14 days."
In the case of a viral chest infection, such as bronchitis, antibiotics are not usually prescribed if a patient was in previously good health.
Where can I get advice?
If you want some general advice, or are unsure about your symptoms the first port of call could also be a pharmacist. "Pharmacists are trained to advise you on managing your symptoms," says Livingstone. "They are also used to recognising the signs of chest infection. If you're unsure, they can be a good place to start."