The problem: round, scaly patches that do not go away
A reddish patch appears on your forearm or neck. It itches a little, you put cream on it, but it does not get smaller, it gets wider, and the centre becomes paler. Or a dry patch that you took for skin affected by indoor heating in winter keeps growing under the cortisone cream from the cupboard. Such patches are easily confused, because fungal infection, eczema, psoriasis and pityriasis rosea can look alike.
A fungal skin infection usually starts as a single red patch with a raised, scaly edge. It spreads out from the centre and forms a ring with a paler centre and a red, scaly rim; itching is common, and the patches are typically not mirrored on both sides of the body (DermNet: Tinea corporis). On light skin the edge often looks red, on darker skin rather darker than the surrounding area (NHS: Ringworm).
The table shows typical patterns from specialist sources. It is a guide, not a diagnosis: only a medical examination, often with a skin sample, gives certainty.
| What you see | What may be behind it |
|---|---|
| Round or oval patch with a red, scaly, raised edge and a paler centre, grows outwards, often itches, usually on one side | fungal infection on the body (tinea corporis) (DermNet: Tinea corporis) |
| Round or oval red, scaly patches on the face, usually on one side, often paler in the centre | fungal infection on the face; easily mistaken for seborrhoeic eczema, rosacea or atopic eczema (DermNet: Tinea faciei) |
| A slowly growing, scaly, dry, mildly itchy area on one palm, often together with athlete's foot | fungal infection on the hand (DermNet: Tinea manuum) |
| Brownish, pale or pink patches with fine scales on the back, chest, neck or arms, often with heavy sweating, often gone in winter | pityriasis versicolor; yeasts that belong to normal skin, not contagious in the usual sense (DermNet: Pityriasis versicolor) |
| A rash that spreads under cortisone cream, with a blurred edge and little scaling or redness | masked fungal infection (tinea incognito) (DermNet: Tinea corporis), (Zacharopoulou et al. 2024) |
Conditions that can resemble a fungal skin infection include discoid eczema, psoriasis, pityriasis rosea and seborrhoeic eczema (DermNet: Tinea corporis). More in Psoriasis in winter: why it often gets worse and how to care for your skin and Pityriasis rosea: how it progresses, skin care and when to see a doctor. For an overview of dry, round patches, see Dry patches on the skin: when harmless, when to see a doctor?; what is different on the feet is explained in Dry feet or athlete's foot? Signs and when to see a doctor.
Why fungal skin infections develop – and what autumn and winter add
Where the fungus comes from. Most skin fungi are dermatophytes, fungi that break down the keratin of the horny layer (Nenoff et al. 2014). The most common pathogen worldwide is Trichophyton rubrum, which is passed from person to person (DermNet: Tinea corporis). The infection often starts on the feet or nails and moves on from there (DermNet: Tinea faciei). A fungal skin infection is contagious through close contact with infected people or animals, via objects such as towels and bedding and, less often, via soil (NHS: Ringworm).
Animals as a source. Cats and dogs can pass on the fungus Microsporum canis (DermNet: Tinea corporis), guinea pigs and other small rodents further species (Nenoff et al. 2014). In a German laboratory, such animal-derived fungi were found in 2.56% of samples from March 2020 to February 2021. The most common was the guinea pig fungus, two thirds of whose cases affected children and adolescents (Uhrlaß et al. 2023).
Autumn plays a role too. In this analysis, some fungi peaked in autumn and winter: Microsporum canis in November, a mouse-derived fungus from September to January, and the guinea pig fungus once more in December after the summer (Uhrlaß et al. 2023). These are data from a single year, but they show that fungal skin infection is not purely a summer topic.
Sport and winter clothing. Contact sports such as wrestling are a known source of fungal infection on the body (DermNet: Tinea corporis), (Nenoff et al. 2014), and small outbreaks also occur in nurseries and schools (Nenoff et al. 2014). Fungi like warmth and moisture; specialist sources advise keeping the skin clean and dry (DermNet: Tinea corporis). Under thick layers and in sportswear you sweat in winter too; more in Sweating in winter: causes and what you can do.
The cortisone trap. In winter, dry, itchy patches are common, and a cortisone cream quickly ends up on them. Cortisone dampens the inflammation, the patch may temporarily look better, but the fungus has not been treated. The rash then spreads, the edge becomes blurred, and scaling and redness recede (DermNet: Tinea corporis). This masked form delays diagnosis and has to be distinguished from eczema, psoriasis or lupus (Zacharopoulou et al. 2024).
The solution step by step
| Step | What you do | Why |
|---|---|---|
| Straight away | Do not scratch the patch, no cortisone cream on suspicion; take a photo to see whether it grows | Scratching spreads the fungus (NHS: Ringworm); cortisone can mask it (DermNet: Tinea corporis) |
| Get it checked | See a pharmacist or doctor; for unclear patches, on the face and after cortisone, see a dermatologist | The diagnosis becomes certain with skin scales from the edge, which are examined under the microscope and cultured (DermNet: Tinea corporis) |
| Treat | Use antifungal medicines from the pharmacy or doctor for as long as the package leaflet or doctor says, even if the patch has already faded; for extensive infection or on hairy skin, the doctor prescribes tablets | Antifungal medicines are continued after the rash has gone (NHS: Ringworm), (DermNet: Tinea corporis); relapses are common (DermNet: Tinea corporis) |
| At home | Do not share towels, combs and bedding, and wash them regularly; wash your hands after contact with animals | The fungus can be passed on via objects (NHS: Ringworm) |
| Look for the source | Check your feet and nails, consider the people you live with; take pets with bald or scaly patches to the vet | Household members and animals are examined and treated to find the source (DermNet: Tinea corporis), (NHS: Ringworm) |
| Prevent | Dry your skin well after sport and showering, change sweaty clothes quickly, wear loose-fitting clothes | Clean, dry skin and loose clothing are recommended by specialist sources (DermNet: Tinea corporis) |
In Germany, a fungal skin infection is not among the diseases listed in section 34 of the Infection Protection Act for nursery and school (IfSG § 34). Let the facility know anyway, because small outbreaks do occur (Nenoff et al. 2014), and ask the doctor when your child should go back.
What helps – and what tends not to
| Measure or home remedy | Assessment |
|---|---|
| Antifungal medicines from the pharmacy or doctor | the usual approach (DermNet: Tinea corporis); which one suits is something your pharmacist or doctor will tell you |
| Cortisone cream on an unclear patch | no: it suppresses the inflammation and can blur the picture (DermNet: Tinea corporis) |
| Home remedies such as vinegar, tea tree oil or garlic | not named as treatment in the specialist sources assessed here; they can irritate the skin further and delay diagnosis |
| Skin care cream or oil on the patch | better not: skin care does not treat a fungus; on an unclear patch it can at most mask the scales |
| Stopping treatment as soon as the patch fades | no: antifungal medicines continue beyond the point where the patch disappears (NHS: Ringworm) |
| A towel and flannel just for you | yes (NHS: Ringworm); this also applies to sponges, more in Loofah sponge: how often to replace it, how to clean and boil it? |
Common mistakes
Taking every round patch for a fungus and using an antifungal cream at random: eczema will not improve with it, and the sample at the doctor's becomes more difficult if treatment has already started. Conversely, putting old cortisone cream from the cupboard on an unclear patch. Stopping treatment as soon as it no longer itches. Not treating your own athlete's foot as well, so that the fungus comes back. Not thinking of the guinea pig or cat, although the child has the patches exactly on the arms used to hold the animal. And: still one towel for everyone.
When should you seek medical advice?
Have the patch looked at by a GP or dermatologist if
- it does not improve after the antifungal medicine from the pharmacy (NHS: Ringworm),
- the scalp is affected; a cream is then usually not enough (NHS: Ringworm),
- your immune system is weakened, for example by chemotherapy, steroids or diabetes (NHS: Ringworm),
- the patch is on the face, because mix-ups are common there (DermNet: Tinea faciei),
- the rash has spread under cortisone (DermNet: Tinea corporis),
- the infection is extensive or affects hairy areas; tablets are then often needed (DermNet: Tinea corporis),
- a baby or toddler is affected, or you are pregnant or breastfeeding; the doctor then chooses the medicine,
- the patch is weeping, oozing pus, develops into a thick, painful lump (DermNet: Tinea faciei) or fever comes on top; then on the same day, outside opening hours via the German out-of-hours medical service on 116 117.
Frequently asked questions
What does a fungal skin infection look like?
Typical is a round, red patch with a scaly, raised edge and a paler centre that grows outwards and often itches. On dark skin it looks rather darker than the surrounding area. Under cortisone it can look atypical.
Is a fungal skin infection contagious?
Yes, through close skin contact, via animals and via towels or bedding. So keep towels separate and wash them regularly. Pityriasis versicolor, on the other hand, is not contagious in the usual sense.
Fungus or eczema: how can I tell?
A fungus often forms a ring with a scaly edge and a pale centre, usually on one side only. Eczema can look very similar, so only a skin sample at the doctor's can tell for certain.
Which cream helps against a fungal skin infection?
Antifungal medicines from the pharmacy or doctor. Ask which one suits and use it for as long as instructed. Cortisone cream alone does not belong on an unclear patch.
Can I catch it from my dog?
Yes, dogs and cats can pass on a fungal skin infection, as can guinea pigs and other small rodents. Wash your hands after stroking them and take animals with bald patches to the vet.
What about a fungal infection on the face?
It shows up as round or oval, red, scaly patches, usually on one side, and is easily mistaken for other skin conditions. See a dermatologist rather than trying creams yourself.
Patches on the back: is it a fungus?
Brownish, pale or pink patches with fine scales on the back are often pityriasis versicolor. It is linked to sweating and often disappears in winter. A ring with a scaly edge points more towards a fungal skin infection.
Do home remedies help against a fungal skin infection?
Vinegar, tea tree oil and the like are not named as treatment in the specialist sources. They can irritate the skin and delay diagnosis. It is wiser to have the patch looked at.
At forpeople
We have nothing against fungal skin infections, and our skin care products do not belong on an unclear or inflamed patch. They are not antifungal medicines. This also applies to our foot care if you suspect a fungus; what to do instead is explained in Skin peeling between the toes: moisture, athlete's foot or dryness?.
Once the fungus has been treated and the skin has closed again, it comes down to perfectly normal care. How to look after dry winter skin without masking a new problem is explained in Itchy skin in winter: showering, care and when to see a doctor.
More on this: Scabies or eczema? How to recognise scabies and what to do now · Impetigo in children: recognising honey-coloured crusts and what to do · Warts on hands and fingers: where they come from and what helps
Sources
- DermNet: Tinea corporis. Created 2003, updated by Bell H (November 2020), accessed 30 October 2026. https://dermnetnz.org/topics/tinea-corporis
- NHS: Ringworm. Last reviewed 3 August 2023, accessed 30 October 2026. https://www.nhs.uk/conditions/ringworm/
- DermNet: Tinea faciei. Updated by Coulson I (2024), reviewed July 2024, accessed 30 October 2026. https://dermnetnz.org/topics/tinea-faciei
- DermNet: Tinea manuum. Created 2003, accessed 30 October 2026. https://dermnetnz.org/topics/tinea-manuum
- DermNet: Pityriasis versicolor. Oakley A (1997), updated September 2014, revised August 2021, accessed 30 October 2026. https://dermnetnz.org/topics/pityriasis-versicolor
- Zacharopoulou A, Tsiogka A, Tsimpidakis A, Lamia A, Koumaki D, Gregoriou S (2024): Tinea incognito: challenges in diagnosis and management. Journal of Clinical Medicine 13(11): 3267. https://doi.org/10.3390/jcm13113267
- Nenoff P, Krüger C, Ginter-Hanselmayer G, Tietz HJ (2014): Mycology – an update. Part 1: Dermatomycoses: causative agents, epidemiology and pathogenesis. Journal der Deutschen Dermatologischen Gesellschaft 12(3): 188–209. https://doi.org/10.1111/ddg.12245
- Uhrlaß S, Mayser P, Koch D, Mütze H, Krüger C, Schulze I et al. (2023): Zoophile Dermatophyten während der Coronapandemie in Deutschland [Zoophilic dermatophytes during the coronavirus pandemic in Germany]. Dermatologie 74(6): 430–439. https://doi.org/10.1007/s00105-023-05150-5
- Infektionsschutzgesetz (IfSG) [German Infection Protection Act], § 34. Accessed 30 October 2026. https://www.gesetze-im-internet.de/ifsg/__34.html
