There are billions of bacteria living on and in the human body. Many of these are helpful and play an important role in keeping us healthy, such as the bacteria found in the gut and on the skin.

Most infections are cleared naturally by the body's immune system. An infection only becomes a problem when it affects a person's health and wellbeing.

Remember, good hand hygiene can help prevent infection.

Common infections and their signs and symptoms

Skin or wound infections

• redness
• heat around the area
• swelling
• discharge
• odour
• pain
• feeling generally unwell.

Bladder infections

• needing to pass urine more often than usual
• blood in the urine
• pain in the lower abdomen or lower back
• feeling generally unwell.

Throat or chest infections

• sore throat or chest discomfort
• cough
• coughing up phlegm
• feeling generally unwell.

Infections can affect many other parts of the body.

If you notice any of these signs or symptoms, contact your GP, nurse or healthcare professional. They will assess the severity of the infection and advise on treatment.

Severity of infection

Mild infection

The body's immune system can clear many mild infections without treatment. Examples include some ear, throat, chest and skin infections.

More serious infection

If an infection does not improve or gets worse, treatment with antibiotics may be needed.

Systemic Severe infection (SSI)

This occurs when infection spreads through the body and causes a person to become seriously unwell.

Examples include:

• pneumonia
• urinary tract infections
• meningitis
• cellulitis
• septic arthritis
• infected wounds.

Treatment may include oral antibiotics or intravenous antibiotics given directly into a vein.

People at higher risk of infection

Some people are at greater risk of developing an infection, including:

• people with conditions that weaken the immune system
• people receiving chemotherapy
• people with diabetes
• people who have recently had surgery or an invasive procedure
• people with an indwelling medical device, such as a catheter or medication line
• people with a history of fever or rigors (shaking)
• people with a history of methicillin-resistant Staphylococcus aureus (MRSA).

If you, or the person you care for, are at higher risk of infection, contact your GP promptly if you suspect an infection.

If you think the infection is severe, contact your GP urgently or call NHS 111.

Sepsis

Infections in people with a higher risk, who are not promptly treated, could develop Sepsis.

Sepsis is a rare but potentially life-threatening condition triggered by infection.

This can affect vital organs, including the:

• brain
• heart
• kidneys.

Signs that may suggest sepsis

Seek urgent medical help if you notice any of the following:

• feeling very hot or very cold
• a temperature below 35.5°C or above 38.3°C
• rapid breathing
• a heart rate above 90 beats per minute
• sudden confusion or unusual drowsiness.

If you think someone may have sepsis, call 999 immediately.

Prompt treatment can improve the chances of recovery.

Adapted from UK Sepsis Trust and Patients UK