The immune system is the central driver for both eczema and psoriasis, and any event that causes the immune system to activate, such as a common cold or a bacterial infection, can have a direct impact on the skin. For many individuals, a flare-up of their skin condition is often the first sign that their body is fighting off a virus. This occurs because the inflammatory chemicals produced by the body to attack an infection do not stay localised to the respiratory tract or the site of injury; they circulate through the bloodstream and can inadvertently trigger inflammation in the skin. Understanding this link is essential for managing chronic skin conditions, especially during the winter months when viral infections are more prevalent in the UK.
What We’ll Discuss in This Article
- The biological mechanism of how infections trigger skin inflammation.
- The link between streptococcal infections and guttate psoriasis.
- Why the common cold can lead to an eczema flare-up.
- The impact of a fever on skin barrier function and itching.
- How the immune system’s focus shifts during an illness.
- Clinical advice for managing the skin during an infection.
How do infections trigger skin inflammation?
When the body detects a virus or bacteria, the immune system releases signalling proteins called cytokines. These proteins are designed to coordinate the body’s defence, but in people with a predisposition to atopic eczema or psoriasis, these same cytokines can trigger the skin’s inflammatory pathways. Essentially, the immune system becomes over-sensitised; while it is busy fighting a cold, it also begins to mistakenly attack the skin or accelerate skin cell production. This systemic overflow of inflammation is why a simple sore throat or a flu-like illness can result in a sudden, widespread worsening of skin patches.
The specific link between strep throat and psoriasis
One of the most well-documented triggers in dermatology is the connection between streptococcal (strep) infections and a specific type of psoriasis called guttate psoriasis. This form of the condition appears as small, drop-like sores across the trunk, arms, and legs. According to the NHS, it is very common for children and young adults to develop guttate psoriasis roughly two to three weeks after having a streptococcal throat infection. For some, this may be their first encounter with psoriasis. The immune response to the bacteria appears to cross-react with the skin, initiating the rapid cell turnover characteristic of the disease.
Why does a cold make eczema worse?
In atopic eczema, the body is already in a state of allergic readiness. When a cold virus enters the system, the resulting inflammation can further weaken the already fragile skin barrier. Additionally, many of the symptoms of a cold, such as a fever, can lead to increased sweating and a rise in skin temperature. Both heat and sweat are known triggers for intense itching. Furthermore, when the body is under the stress of an infection, it produces more cortisol, which, while anti-inflammatory in the short term, can eventually lead to a rebound flare-up as levels fluctuate.
The role of the skin barrier during illness
When you are unwell with an infection, the body prioritises vital organs, which can sometimes lead to the skin receiving less hydration and nutrients. This can make the skin feel drier and more brittle than usual. If an infection is accompanied by a fever, the skin can lose moisture even more rapidly through evaporation. NICE guidance emphasises that during periods of illness, it is even more important to maintain a rigorous emollient routine to provide the skin with a physical shield while the immune system is distracted by the infection.
Managing your skin while you are unwell
If you notice your skin condition is worsening while you have a cold or infection, it is important to treat the skin proactively. Healthcare professionals in the UK generally recommend:
- Increasing emollient use: Apply moisturisers more frequently to combat the drying effects of a fever or infection.
- Managing the infection: Treating the underlying illness, such as using antibiotics for a confirmed bacterial infection, is often the only way to get the skin flare-up to settle.
- Avoiding hot baths: While they may feel soothing when you have a cold, hot water can further strip the skin of oils and worsen the itch.
- Rest and hydration: Helping the body recover from the infection quickly will reduce the duration of the systemic inflammatory response.
Can the infection itself be in the skin?
It is important to distinguish between a systemic infection (like a cold) triggering a flare-up and the eczema or psoriasis becoming infected itself. If the skin patches become wet, weepy, or covered in golden crusts, this indicates a secondary bacterial infection of the skin. This requires different treatment, usually in the form of topical or oral antibiotics. Systemic infections like the flu can lower your overall immunity, making you more susceptible to these secondary skin infections.
Conclusion
Infections and common colds are significant clinical triggers for both eczema and psoriasis because they activate the same inflammatory pathways that drive these skin conditions. From the drop-like patches of guttate psoriasis following a sore throat to the increased itching of eczema during a fever, the skins health is closely tied to the immune systems activity. By recognising this link and increasing skin protection during periods of illness, patients can better manage the impact of seasonal viruses on their skin health.
If you experience a sudden, widespread rash accompanied by a very high fever, a stiff neck, or a headache that does not go away, call 999 immediately.
Why does my psoriasis flare up after I have a sore throat?
Bacteria like streptococcus can trigger a specific immune response that cross-reacts with your skin cells, often leading to guttate psoriasis.
Should I stop my skin creams if I have a fever?
No; it is actually more important to use your emollients during a fever to prevent the skin from drying out and cracking.
Can a cold sore trigger an eczema flare?
Can a cold sore trigger an eczema flare? Yes, the herpes simplex virus can not only trigger a general flare but can also lead to a serious complication called eczema herpeticum if it enters broken skin.
Will my skin clear up as soon as my cold goes away?
Usually, the skin will start to improve once the infection is gone, but you may need to continue your prescribed treatments for a short while longer to fully calm the inflammation.
Can vaccines trigger a flare-up?
Like any event that stimulates the immune system, some people notice a mild, temporary flare after a vaccination, but this is generally considered a minor risk compared to the benefits of the vaccine.
Is it normal for my skin to feel hot when I am sick?
Yes, a fever or systemic inflammation increases blood flow to the skin, which can make it feel warm, red, and more itchy.
Can antibiotics help my eczema?
Antibiotics will only help if the eczema itself has a secondary bacterial infection; they will not treat a standard eczema flare caused by a cold virus.
Authority Snapshot (E-E-A-T Block)
This article explores the relationship between systemic infections and inflammatory skin conditions to assist patients in managing seasonal flare-ups. It is written by the MyPatientAdvice Medical Writing/Research Team and reviewed by Dr. Rebecca Fernandez, a UK-trained physician with experience in internal medicine and emergency care. All information is aligned with the clinical diagnostic standards provided by the NHS and NICE.
