Staphylococcal infections - Symptoms of staphylococcal infections

The symptoms of staphylococcal infections vary depending on the type of infection you have.

Staphylococcal skin infections

Staph infections most commonly affect the skin. Symptoms for the most common types of staphylococcal skin infections are outlined below.

Boils

A boil is a red, painful, lump on the skin that usually develops on the neck, face, armpit or buttocks. When a boil first forms, it appears as a swollen, painful red lump. As it grows, yellowish-white pus builds up at the centre of the boil.

As tempting as it may be, it is important not to squeeze a boil because it can lead to complications.

In most cases, the boil will eventually burst within a few weeks and the pus will drain away, leaving the skin to heal.

Read more about the symptoms of boils.

Skin abscess

An abscess is a painful collection of pus that may appear as a lump under the surface of the skin or an open break in the skin.

The abscess may get larger and more painful as the infection continues and more pus is produced.
Staphylococcal infections can cause skin abscesses on the head and neck, limbs, underarms and torso.

Read more about the symptoms of a skin abscess.

Folliculitis

A hair follicle is a small sac in the skin that a hair grows out of. If a hair follicle becomes infected with staphylococcus bacteria then itchy, white bumps filled with pus can appear.

If the infection is deep in the skin, the infected hair follicle may develop into a boil (see above) and become more painful.

Impetigo

Impetigo is a highly contagious bacterial skin infection that mainly affects children. It does not affect the deeper skin layers. There are two types of impetigo:

• non-bullous impetigo - which causes sores that quickly rupture, leaving a yellow-brown crust
• bullous impetigo - which causes large, painless, fluid-filled blisters (bullae)

The sores and blisters caused by both types of impetigo are usually very itchy. However, you should avoid scratching them because it can spread the infection to other parts of your body and the bacteria easily spread through close contact.

Read more about symptoms of impetigo.

Cellulitis

Cellulitis is a bacterial infection of the deep layer of the skin (dermis) and the layer of fat and soft tissues (the subcutaneous tissues) that lie underneath the skin.

Cellulitis causes your skin to become:

• red
• painful
• hot
• swollen
• tender
• blistered

Cellulitis can make you feel generally unwell and cause you to feel sick (nausea) or have shivers and chills.

Read more about the symptoms of cellulitis.

Wound infection

Any wound has the potential to become infected, including cuts and grazes or surgical wounds.

Symptoms include:

• redness, swelling and pain at the site of the wound
• a discharge of pus or liquid from the wound
• the wound healing much slower than would usually be expected
• an unpleasant smell coming from the site of the wound

Staphylococcal scalded skin syndrome

Probably the most serious type of staphylococcal skin infection is staphylococcal scalded skin syndrome (SSSS), which most commonly affects babies and young children under five.

In this type of infection, the staphylococcal bacteria release a toxin (poison) that damages the skin, leading to extensive blistering which looks like the skin has been scalded by boiling water.

Other symptoms of SSSS include:

• painful skin
• a high temperature (fever) of 38C (100.4F) or above
• large areas of skin peeling off or falling away
• redness of the skin which usually spreads across the entire body

Invasive staphylococcal infections

Invasive staph infections are uncommon but potentially serious. Some of the types and their symptoms are described below.

Septic arthritis

Septic arthritis is a condition where a joint becomes infected with the S. aureus bacteria. Symptoms of septic arthritis include:

• joint pain and swelling
• red and tender skin around the joint
• a high temperature (fever) of 38C (100.4F) or above

Read more about septic arthritis.

Septic bursitis

In septic bursitis, the bursa becomes infected. A bursa is a small fluid-filled sac which forms under the skin, usually over the joints and between tendons and bones.

Symptoms of septic bursitis include:

• pain, swelling and tenderness in the affected body part which feels warm to the touch
• a high temperature (fever) of 38C (100.4F) or above
• chills

Read more about the symptoms of septic bursitis.

Pyomyositis

Pyomyositis is an infection of the muscles used to move and support the bones of the skeleton. It is more common in tropical areas of the world.

Symptoms of pyomyositis include:

• a very high temperature, which can be as high as 40C (104F)
• chills
• pain and swelling in the affected muscles
• the muscles feel soft and spongy to the touch due to the presence of pus

Osteomyelitis

Osteomyelitis is a bone infection. One of the larger leg bones is usually affected.

Symptoms of osteomyelitis include:

• a sudden high temperature
• bone pain, which can often be severe
• swelling, redness and warmth at the site of the infection
• a general sense of feeling unwell
• the affected body part is tender to touch
• a restricted range of movement in the affected body part

Read more about the symptoms of osteomyelitis.

Pneumonia

Pneumonia is an infection of the lungs. Symptoms of pneumonia include:

• difficulty breathing - your breathing may be rapid and shallow and you may feel breathless, even when you are resting
• rapid heartbeat (tachycardia)
• a high temperature (fever) of 38C (100.4F) or above
• feeling generally unwell
• pain in your chest

Read more about the symptoms of pneumonia.

Toxic shock syndrome

Toxic shock syndrome is a rare condition caused when S. aureus bacteria enter the bloodstream and begin to release toxins (poisons). Most people are immune to the effects of the toxins, however in some people, the toxins can cause a drop in blood pressure and organ and tissue damage. The S. aureus can be found in a small wound, or associated with periods and using tampons.

Symptoms of toxic shock syndrome include:

• a sudden high temperature
• vomiting
• a skin rash that looks like sunburn
• diarrhoea 
• fainting or feeling faint
• muscle aches
• confusion

Read more about the symptoms of toxic shock syndrome.

Endocarditis

Endocarditis is an infection of the inner layer of the heart, particularly affecting the heart valves. The symptoms of endocarditis can sometimes develop gradually over many weeks or quickly over a few days.

Symptoms of endocarditis, caused by a staphylococcal infection, include:

• a high temperature (fever) of 38C (100.4F) or above
• chills and shivers
• muscular aches and pains
• chest pain
• coughing
• weakness and fatigue (extreme tiredness)
• headache
• shortness of breath

Read more about the symptoms of endocarditis.

Sepsis

Sepsis, also known as blood poisoning, can be due to any bacteria. The symptoms usually develop quickly and include:

• a high temperature (fever) of 38C (100.4F) or above
• fast heartbeat (tachycardia)
• fast breathing
• low blood pressure (hypotension), which causes you to feel dizzy when you stand up
• a change in mental behaviour, such as confusion or disorientation
• diarrhoea 
• loss of consciousness

Sepsis is a medical emergency. Dial 999 to request an ambulance if you suspect that you or someone in your care is experiencing sepsis.

Read more about sepsis. 

Staphylococcal food poisoning

The symptoms of staphylococcal food poisoning develop quickly after eating contaminated food (usually within 30 minutes to six hours). They include:

• feeling sick (nausea)
• being sick
• stomach cramps
• diarrhoea 

These symptoms should pass within one to three days. However, if your symptoms persist beyond this time, or if they worsen rapidly, you should contact your GP for advice.

Read more about the symptoms of food poisoning.