What does MRSA look like?
Most MRSA infections show up on skin as a painful red bump that grows fast and fills with pus. Here is every common form, how the colour and shape change over the first week, and the visual signs that mean urgent care.
The short answer
MRSA usually looks like a painful red bump that resembles a spider bite or an angry pimple, becomes warm and swollen, and develops a white or yellow pus-filled centre within a day or two. It grows faster than a normal pimple, hurts more than it should for its size, and often has a halo of redness around it.
The common visual forms
MRSA does not have a single appearance. Depending on where it starts, how deep it goes, and how the immune system responds, the same bacterium can look like any of the following.
Small red bump
The classic first appearance: a firm, tender, red bump 5 to 15 mm across, often mistaken for a spider bite or ingrown hair. The bump is warmer than surrounding skin and painful to press.
Pustule with a white or yellow head
Within a day or two the bump develops a pus-filled centre. It resembles a large, angry pimple but is more painful and grows faster. The surrounding skin is red and warm.
Boil (furuncle) or carbuncle
A deep, walled-off collection of pus, often 2 to 5 cm across. Carbuncles are clusters of connected boils. Both are tense, exquisitely painful, and typically require incision and drainage in addition to antibiotics.
Abscess
A fluctuant, fluid-filled lump under red, thin, shiny skin. Pressing gently reveals a wave of pus underneath. Untreated abscesses can rupture, seed the bloodstream, or extend into deeper tissue.
Cellulitis
A spreading warm, red, tender patch of skin around the original lesion — no defined edge, no pus collection. The skin often looks glossy and can feel tight. Red streaks tracking away from the area are a warning sign.
Folliculitis
Multiple small pus-filled bumps centred on hair follicles, often on the thighs, buttocks, or back. Individually they look like tiny pimples; grouped and persistent, they raise suspicion for MRSA — especially after shaving or in athletes.
Impetigo-like crusting
Especially in children, MRSA can produce shallow blisters that rupture and leave honey-coloured or yellow crusts around the nose, mouth, or on the limbs. It looks identical to classic strep impetigo and only a swab tells them apart.
How it changes day by day
A typical untreated MRSA skin infection follows a recognisable visual progression. Day 1–2: small red bump that looks like a bite or pimple. Day 2–4: the bump enlarges, feels warm, and develops a pus-filled centre. Day 4–7: a fluctuant abscess forms or the surrounding skin becomes red and warm as cellulitis develops. Day 7+: fever, red streaks tracking from the lesion, or rapidly spreading redness signal the infection is moving beyond the skin.
See the full stage-by-stage breakdown on our MRSA symptoms page →
Visual red flags — seek same-day care
- Red streaks tracking away from the lesion (lymphangitis)
- Rapidly spreading redness or a lesion that doubles in size overnight
- Dusky, purple, or blackened skin over or around the lesion
- A widespread red 'sunburn-like' rash with fever
- A lesion on the face, particularly near the eye or upper lip
- Fever or chills accompanying any skin lesion
You cannot diagnose MRSA by looking
Every appearance above can also be caused by MSSA (methicillin- sensitive Staph aureus), streptococcus, or other bacteria. A clinician confirms MRSA with a swab or culture. More information on our MRSA test page →
For a full guide to the types, diagnosis, and treatment of MRSA skin infections, see the MRSA skin infection page →
If the lesion is aggressive, systemic symptoms are present, or the person is immunocompromised, invasive disease is a concern. More information on our invasive MRSA page →
Frequently asked questions
More information on our symptoms, treatment, and transmission pages.
Symptoms hub
Overview of MRSA symptoms and day-by-day progression.
MRSA rash
Does MRSA cause a rash? Look-alikes and how to tell them apart.
MRSA in the nose
Nasal carriage vs infection, swab testing and mupirocin treatment.
MRSA skin infection
Types, diagnosis, treatment, and when skin MRSA becomes dangerous.
MRSA boil
Deep, painful, pus-filled lumps and how they are drained.
MRSA cellulitis
Spreading deeper-skin infection and urgent warning signs.
MRSA folliculitis
Small pus-filled bumps around hair follicles and prevention.
MRSA pneumonia
Hospital, ventilator-associated and necrotising lung infection.
MRSA bacteremia
MRSA in the bloodstream — how it gets there and how it's treated.
MRSA sepsis
Can MRSA cause sepsis? Warning signs and survival rates.
Invasive MRSA
How MRSA reaches the bloodstream, lungs and bone.
MRSA test
PCR nasal swab, wound culture and susceptibility testing.
MSSA vs MRSA
Same bacterium, different antibiotic susceptibility.
Staph infection vs pimple
How to tell a normal pimple from a staph or MRSA skin lesion.