Pneumococcal infections

About pneumococcal infections

Pneumococcal infections are caused by the Streptococcus pneumoniae bacteria, and range from mild to severe.

There are more than 90 different strains of Streptococcus pneumoniae (S. pneumoniae) bacteria (known as serotypes), some of which cause more serious infection than others.

The symptoms of a pneumococcal infection can vary, depending on the type of infection you have. Common symptoms include:

  • a high temperature (fever) of 38C (100.4F)
  • aches and pains
  • headache

Types of pneumococcal infection

Pneumococcal infections usually fall into one of 2 categories:

  • non-invasive pneumococcal infections – these occur outside the major organs or the blood and tend to be less serious
  • invasive pneumococcal infections – these occur inside a major organ or the blood and tend to be more serious

Non-invasive pneumococcal infections

Non-invasive pneumococcal infections include:

  • bronchitis – infection of the bronchi (the tubes that run from the windpipe down into the lungs)
  • otitis media – ear infection
  • sinusitis – infection of the sinuses

Invasive pneumococcal infections

Invasive pneumococcal infections include:

  • bacteraemia – a relatively mild infection of the blood
  • septicaemia (blood poisoning) – a more serious blood infection
  • osteomyelitis – infection of the bone
  • septic arthritis – infection of a joint
  • pneumonia – infection of the lungs
  • meningitis – infection of the meninges (the protective membranes surrounding the brain and spinal cord)

Who is at risk?

People with a weakened immune system are most at risk of catching a pneumococcal infection. This may be because:

  • they have a serious health condition, such as HIV or diabetes, that weakens their immune system
  • they are having treatment or taking medication that weakens their immune system, such as chemotherapy

Other at-risk groups include:

  • babies and young children under 2 years of age
  • adults over 65 years of age
  • people who smoke or misuse alcohol

Read more about the causes of pneumococcal infections.

Cases of invasive pneumococcal infection usually peak in the winter, during December and January.

Treating pneumococcal infections

Non-invasive pneumococcal infections are usually mild and go away without the need for treatment. Rest, fluids and over-the-counter painkillers such as paracetamol are usually advised.

More invasive types of pneumococcal infections can be treated with antibiotics, either at home or in hospital.

Read more about how pneumococcal infections are treated.

Pneumococcal vaccines

A pneumococcal infection can affect anyone, but some people are at higher risk of serious illness and can get the pneumococcal vaccine free from the NHS.

These people include:

  • babies as part of the childhood immunisation programme, given at 8 and 16 weeks and between 12 and 13 months of age
  • adults aged 65 and over
  • children and adults with certain long-term health conditions, such as a serious heart or kidney condition.

If you’re unsure whether you or your child should get the vaccine, speak to your GP or practice nurse.

Getting the vaccine’s the best way to help protect yourself against infections caused by the most common types of pneumococcal bacteria. It doesn’t protect you against infections caused by all pneumococcal bacteria, so it’s important you know the signs and symptoms.

Read about the pneumococcal immunisation for adults and pneumococcal immunisation for babies


The outlook for pneumonia in people who are otherwise healthy is good, but the infection can lead to serious complications in people who are very young, very old or have another serious health condition.

However, due to the introduction of the PCV in 2002, the number of people dying from complications that arise from pneumonia has fallen to around 7%.

The outlook for other types of invasive pneumococcal infections such as bacteraemia is generally good, although there is about a 1 in 20 chance that bacteraemia will trigger meningitis as a secondary infection.

Multidrug-resistant Streptococcus pneumoniae (MDRSP)

During the 1990s, the increasing levels of S. pneumoniae that had developed a resistance to 3 or more types of antibiotics was a major concern. These types of bacteria are known as multidrug-resistant Streptococcus pneumoniae (MDRSP).

MDRSP is a real concern because it is challenging to treat and carries a higher risk of causing complications.

Since the introduction of pneumococcal vaccines, fewer cases of infection have led to antibiotics being used less and the chance of bacteria developing resistance to antibiotics becoming smaller.

The ability for bacteria to become resistant to antibiotics is the reason why GPs are becoming increasingly reluctant to prescribe antibiotics for mild infections.

Symptoms of pneumococcal infections

Your symptoms will vary, depending on the type of pneumococcal infection you have.

Some common symptoms include:

  • a high temperature (fever) of 38C (100.4F) or above
  • chills
  • sweats
  • aches and pains
  • headache
  • a general sense of feeling unwell

When to seek emergency medical advice

The most serious type of pneumococcal infection is bacterial meningitis, which requires immediate admission to hospital for emergency treatment.

Bacterial meningitis has a number of early warning signs that can occur earlier than the other symptoms.

These are:

  • pain in the muscles, joints or limbs – such as in the legs or hands
  • shivering or unusually cold hands and feet
  • blue lips and pale or blotchy skin

Go to A&E or phone 999 if:

  • you have a blotchy, red rash that does not fade or change colour when you place a glass against it
  • you experience drowsiness or confusion
  • you have a seizure or fit
  • you have an inability to tolerate bright lights – known as photophobia (less common in young children)
  • you have a stiff neck (also less common in young children)
  • you have a rapid breathing rate
  • your baby becomes floppy and unresponsive or stiff with jerky movements
  • your baby is becoming irritable and not wanting to be held
  • your baby is crying unusually

You should phone 999 immediately and request an ambulance if you think you or someone around you has bacterial meningitis.

Read more about meningitis

Contact your GP or, if your GP’s closed, phone 111 if:

  • you have a constant high temperature that lasts for more than 3 days
  • you cough up mucus streaked with blood
  • you develop rapid breathing (more than 30 breaths a minute) or chest pains
  • you become drowsy or confused
  • you experience shortness of breath or other breathing difficulties
  • your child is under three months and has a temperature of 38C or above
  • your child is over 3 months and has a temperature of 39C or above
  • your child is over 2 years of age and their symptoms persist for more than 3 days

You should also contact your GP if you have any of the risk factors that make you more vulnerable to developing a pneumococcal infection.

Read about the causes of pneumococcal infections for more information about these risk factors.

Causes of pneumococcal infections

There are more than 90 different strains of S. pneumoniae, and some are much more likely to cause serious infection (virulent) than others.

Some strains can be easily killed by the immune system, while others are resistant and likely to cause a more serious infection.

It’s thought that between 8 and 10 strains are responsible for two-thirds of serious infections in adults, and most cases in children.

How the bacteria is spread

S. pneumoniae enter the human body through the nose and mouth, and an infection can be spread in the same way as a cold or the flu. This can be through:

  • direct contact – for example, when someone coughs or sneezes, tiny droplets of fluid that contain the bacteria are launched into the air and can be breathed in by others
  • indirect contact – for example, if infected droplets of fluid are transferred from someone’s hand to a door handle, someone else who touches the handle may become infected with the bacteria if they then touch their nose or mouth

It’s important to emphasise that pneumococcal infections are far less contagious than a cold or flu. This is because most people’s immune systems are able to kill the bacteria before they have the opportunity to cause an infection.

Outbreaks of pneumococcal infections can sometimes occur in environments where there are many people who have poorly functioning immune systems, such as in children’s nurseries, care homes for the elderly and homeless shelters.

Risk factors

People with a weakened immune system, either due to their age or general health, are particularly at risk of developing a pneumococcal infection.

The bacteria can move from their throat to other parts of their body, such as the lungs, the blood or the brain. If this occurs, a more serious infection can develop.

The pneumococcal vaccine is offered for free to people at higher risk of pneumococcal infection, including:

  • children under 2 years of age as part of the childhood immunisation programme
  • adults over 65 years of age
  • anyone between the ages of 2 and 65 with a long-term health condition

You’re considered to be at a higher risk of pneumococcal infection if you:

Diagnosing pneumococcal infections

There are several ways to diagnose pneumococcal infections, and the tests you have will depend on your symptoms.

Physical examination

If a pneumococcal infection is suspected, your GP will listen to your chest with a stethoscope. The fluids produced during an invasive pneumococcal infection often cause a distinctive crackling sound.

Blood test

You may have a blood test to check for the presence of bacteria. A high number of infection-fighting white blood cells may indicate the presence of an infection. The blood sample can be sent to a laboratory so the bacteria that caused the infection can be identified.


Several different types of imaging tests may be used, depending on your symptoms.

X-rays may be able to highlight the presence of fluid in the lungs, which would indicate a lung infection. An X-ray uses radiation to produce images of the inside of the body.

Other imaging tests that may be used to investigate a potential pneumococcal infection include:

Blood pressure test

Your blood pressure may be measured, as a serious infection can often lead to a decrease in blood pressure.

Lumbar puncture test

A lumbar puncture test involves taking a sample of cerebrospinal fluid (the fluid that surrounds the brain and spine) from the base of your spine and checking it for the presence of bacteria. A local anaesthetic will be used to numb the area. If the sample contains infection-fighting white blood cells and/or bacteria, it may indicate that you have meningitis.

Urinary antigen test

A urinary antigen test is a relatively new type of test used to help diagnose a pneumococcal infection.

It involves taking a urine sample, then carrying out a technique known as an immunochromatographic assay. This can detect the distinctive protein molecules that make up the outer shell of the S. pneumoniae bacteria.

Treating pneumococcal infections

The treatment you receive depends on whether you have an invasive or non-invasive pneumococcal infection. Antibiotics are often used to treat a serious infection.

Non-invasive pneumococcal infections

Non-invasive pneumococcal infections, such as sinusitis or bronchitis, will usually clear up within a week without the need for treatment.

Drinking plenty of fluids, getting plenty of rest and taking over-the-counter painkillers, such as paracetamol, should help relieve your symptoms.

Read more information about treating specific types of pneumococcal infection:

Invasive pneumococcal infections

If you have an invasive pneumococcal infection, such as pneumonia, a decision will be made about whether you are well enough to be treated at home or need to be admitted to hospital.

Most GPs use a scoring system, known as the CRB-65 score, to assess the potential seriousness of a case of pneumonia.

  • C stands for confusion – if you are mentally confused, you may have a more serious infection
  • R stands for respiratory rate – your respiratory rate is how many breaths you take in a minute; more than 30 breaths a minute may be a sign that your lungs are not working properly
  • B stands for blood pressure – low blood pressure can be a sign of a more serious infection
  • 65 indicates whether you are 65 years of age or over – older people are more vulnerable to infections

Each of the above criteria is given a score of either 0 or 1, depending on whether or not it is applicable. The scoring system is explained below:

A CRB-65 score of 0 means you have a low risk of complications and can usually be treated at home.

A CRB-65 score of 1 to 2 means you have a medium risk of developing complications, and you should have a same-day assessment by an expert in treating pneumonia. Depending on the results of the assessment, you may be treated at home or be admitted to hospital.

A CRB-65 score of 3 or more means you have a high risk of developing complications and you should be admitted to hospital for urgent treatment.

Hospital admission is also recommended for:

  • any type of invasive pneumococcal infection that has developed in a baby or child younger than 2 years of age
  • all cases of suspected meningitis

Treatment at home

If you are being treated at home, you will usually be prescribed a 7-day course of antibiotics and asked to get plenty of rest and fluids.

It’s very important to finish your course of antibiotics, even if you start to feel better. Not completing the full course of antibiotics could cause the pneumonia to return.

Treatment at hospital

If your symptoms are moderate, you can usually be treated with antibiotic tablets.

If your symptoms are severe, you will usually be given antibiotics through a drip into your arm. You may also be given fluids to stop you becoming dehydrated, and oxygen to help you breathe.

Depending on how well you respond to treatment, it may be possible to switch from a drip to antibiotic tablets after a few days.

Most people who are treated in hospital require a 7 to 10 day course of antibiotics. The time it will take before you are well enough to return home will depend on your general state of health and whether you experience a more serious type of pneumococcal infection, such as meningitis.


It’s usually recommended that you attend a follow-up examination 6 weeks after the start of your symptoms. This is to check that the infection has not caused any serious or permanent damage to the affected parts of your body, such as your lungs.

The follow-up examination usually involves taking a chest X-ray so the state of your lungs can be assessed.

Read more information about:

Preventing pneumococcal infections

You can help prevent the spread of a pneumococcal infection by taking some simple hygiene precautions.

These include:

  • washing your hands regularly and thoroughly, particularly after touching your nose and mouth, and before handling food
  • coughing and sneezing into a tissue, throwing it away immediately and washing your hands
  • not sharing cups or kitchen utensils with others

Pneumococcal immunisation

Pneumococcal immunisation is very effective at preventing pneumococcal infections.

Pneumococcal vaccine for babies

All babies are offered pneumococcal immunisation as part of the NHS childhood immunisation schedule.

They’ve 3 doses, which are given:

  • at 8 weeks
  • at 16 weeks
  • between 12 and 13 months of age

The pneumococcal vaccine for babies is entirely safe, although around one baby in 10 will have some redness and swelling at the site of the injection, and symptoms of a mild fever. However, these side effects will pass quickly.

Speak to your GP or health visitor if you are not sure whether your child has received their pneumococcal immunisation.

Pneumococcal vaccine for adults

Adults can have the pneumococcal vaccine or ‘pneumo jab’ for free if they’re in a high-risk group for developing a pneumococcal infection.

If you think you could be eligible for the pneumococcal vaccine, speak to your GP or practice nurse to arrange an appointment.

Healthy adults usually only need 1 dose of the pneumo jab. However, if you’ve a weakened immune system or spleen disorder, you may need additional booster doses. Your GP can advise you about this.

After you’ve had the pneumo jab, you may experience some pain and inflammation at the site of the injection. This should last no longer than three days. Less commonly, some people report the symptoms of a mild fever. Again, this should pass quickly.

Read more about potential side effects of the pneumococcal vaccine.


There is an increasing body of evidence that suggests that people who drink excessive amounts of alcohol are at a greater risk of developing invasive pneumococcal infections.

Alcohol is known to suppress the immune system – the body’s natural defence system that will attempt to prevent an invasive pneumococcal infection.

Therefore, the best way to lower your risk of developing a pneumococcal infection is to ensure that you stick to the recommended daily amounts of alcohol.

Speak to your GP if you’re finding it difficult to moderate your alcohol consumption. Counselling and medication are available for people with an alcohol misuse problem.

Read about alcohol and alcohol misuse for more information and advice.


Smoking is the single biggest risk factor for developing an invasive pneumococcal infection in otherwise healthy adults.

Research has found that almost 60% of previously healthy people who develop an invasive pneumococcal infection are smokers.

It’s not known exactly why smoking makes a person more vulnerable to an invasive pneumococcal infection. One theory is that the chemicals contained in tobacco smoke disrupt the normal workings of the immune system and make it less efficient.

As well as reducing your risk of developing an invasive pneumococcal infection, giving up smoking will help reduce your risk of developing other serious health conditions, such as cancer, heart disease and stroke.

If you want to give up smoking, a good first step is to see your GP. They will be able to provide help and advice about quitting, and can also refer you to an NHS Stop Smoking support service.

These services offer the most effective support for people who want to give up smoking. Studies show you are four times more likely to successfully give up smoking if you do it with the help of the NHS.

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Last updated:
15 June 2023