A cold sore is a small blister on the face that is caused by the herpes simplex virus (HSV). The blister pops and then gets a crust over it. Some people experience tingling or burning before the blister appears and it can be painful. They are very common, with around 1 in 5 people suffering from repeated cold sores. They usually heal by themselves between seven and 10 days. Most people are infected with the virus when they are young, but they may not get a cold sore until many years later. Once infected, the virus stays within you and can be reactivated and cause other cold sores at future points. This is usually around times of stress, tiredness, menstruation, illness or some people find the sun can cause outbreaks. Genital herpes and cold sores are caused by the same virus, although there are two different strains (HSV1 and HSV2). It's not really important which one is causing trouble, as treatment is based on symptoms. If you have symptoms in your genital area, see your doctor or a sexual health doctor to discuss this.

A yeast called candida can be responsible for infections in the mouth, on the skin and around the genital area. Doctors call the infection candidiasis, but it’s known to most as thrush. Yeast infections are more common in people who are pregnant, those taking antibiotics, or those who are prone to infections due to other medical conditions, such as poorly controlled diabetes or immunosuppression. It is common in the mouths of children and babies, and can be common in people who wear dentures. Most women will suffer from a vaginal thrush infection at some point in their life. Yeast infections are easily treated with antifungal medications. Depending on where your infection is and how widespread, these come in the form of oral drops, pessaries, creams or tablets.

Under its fancy Greek title of xeros (dry) and derma (skin), dry skin can be intensely itchy. It feels rough and flakes easily. Cracks and redness can form in more severe cases. It affects both sexes and is more common in Caucasian skin than those whose skin has a higher oil content, such as Afro-Caribbean or Mediterranean skin types. Children can be particularly at risk, and this may take the form of eczema - where inflammation of the uppermost layer of skin causes dryness, and this is most likely to appear on the insides of elbows or the backs of knees. Eczema may run in families or go alongside asthma or hay fever. Dry skin is a variant of normal skin and is not contagious.

Warts and verrucas are caused by a harmless viral infection in the skin called the human papilloma virus (HPV). HPV causes keratin, a hard protein in the top layer of the skin, to grow too much, giving the typical roughened texture of a wart. There are more than 60 different types of viruses known to cause warts, this includes genital warts. They are increasingly common through childhood and adolescence but then their frequency drops drastically again on reaching adulthood. Warts often look different depending on where they are on the body and how thick the skin is, and a wart on the sole of the foot is called a verruca. What do they look like? Warts on the hands are found most frequently around the nails and on the fingers and are often shaped like a cauliflower, whereas verrucas are seen most commonly on the ball of the foot as areas of flat, thicker skin with a harder edge around a softer centre.

Vitiligo occurs when pigment (melanin) is lost from areas of skin, leaving behind white patches. The patches can grow in size and merge. These patches may be a little itchy but are not otherwise bothersome. The main complaint is the appearance of these patches, and the loss to self-confidence that comes with it. This requires specialist attention to treat, with the aim of stopping new patches forming, and if it's caught early enough, there's the possibility of reversing white areas to allow pigment to gradually come back. For this reason, it's important to see your doctor.

A shingles rash is caused by a virus called herpes zoster, and starts as tiny red bumps or blotches that then become weeping blisters (known as vesicles). This most often appears on the chest, back, stomach, neck or face. People sometimes notice a tingling or burning in the days before the rash appears, and may have a headache, mild fever or feel otherwise unwell. It is distinctive in that it will only appear on one half of the body, and usually only covers a small area. This virus was originally caught as chickenpox (varicella zoster virus), usually in childhood. While your body recovers from this, the virus lays asleep, or dormant, in the nerves and is reactivated under stress or illness, usually in those over 60 years old. Following the pathway of nerves means the virus is only activated from the nerves leading off the spine to one side or the other - a so-called dermatomal distribution.

This is a rash where the skin becomes inflamed, appearing on greasy areas with lots of sebaceous glands - on the cheeks, between eyebrows, the folds next to the nose and the chin, and also on the chest or scalp. Red, greasy, scaly or flaky patches are common and little red bumps known as papules may appear. It can cause a mild itch but it's that appearance prompts most sufferers to seek treatment. It is considered to be a type of eczema, but can also overlap with psoriasis and rosacea. Stress, tiredness and cold weather can prompt flare-ups in those susceptible. An overgrowth of a usually harmless yeast (posh name: Malassezia) is thought to be part of the cause, so treatment focuses on eradicating this and dampening down inflammation using a combined antifungal and mild steroid cream.

An SCC (squamous cell carcinoma) is usually a firm pink or red lump and typically occurs in sun-exposed areas like the face, ears, forearms and hands, shoulder, upper chest and back. It might feel tender to press, it may develop a solid horny lump sticking up and it can sometimes ulcerate, giving a wet appearance. This grows slowly over weeks, months or even years. It usually occurs in people aged over 50, in response to years of sun damage. While skin cancers all develop in response to sun damage, and similar risk factors make some more susceptible than others, there are different types of skin cancer. Melanoma is the most well-known, but actually the less common. This is where a new mole appears or an existing mole changes. SCC is a different process and doesn't usually start as a mole.

Psoriasis is a long-term condition that causes thickened patches to appear on the skin. It can only affect the scalp, or you might have other patches on your body. It can be intensely itchy and in a mild form, may cause red patches, usually at the back of the head and extending to the neck or behind the ears. In a more severe form, thickened plaque may cause temporary loss of hair, and this requires stronger and more prolonged treatment.

Rosacea is a common condition that causes redness on the cheeks and across the nose, and is sometimes accompanied by more persistent red bumps, known as papules or pustules if they have a yellow centre. Its full name is actually acne rosacea. Episodes of flushing may precede a more persistent redness. Certain triggers are thought to cause blood vessels just under the skin to widen, becoming more visible and causing redness, but the underlying cause is not well understood. It is common – affecting up to 10% of people – and typically appears in those aged 30 to 60 as well as in fair-skinned/blue-eyed people. The exact cause remains unknown, but triggers for its development include sun damage, leaky tiny blood vessels under the skin, a skin mite called \* Demodex folliculorum \*, and a family history of rosacea. It is not contagious, so you cannot catch it from someone else.

Psoriasis is a long-term skin condition that typically starts off as red areas of skin, perhaps 1 to 2 cm wide, with a slightly raised, dry and flaky surface. It most often affects knees, elbows, lower back and around the hairline, but it can appear anywhere including in the body flexures such as the armpits or groin. It may be a little itchy, especially if the scalp is affected, but is not usually painful.

Monkeypox – sometimes known as mpox - is a relatively rare disease that entered common public knowledge in 2022, as an outbreak spread within Europe including the UK. Cases are normally restricted to western and central Africa, usually causing only a mild illness. Monkeypox is a virus from the same virus family as smallpox, a devastating condition that has been defeated worldwide but it is very different from the COVID-19 or chickenpox viruses. It is called monkeypox because it was first discovered in monkeys in 1958. It then took 10 years for the first cases to be recorded in humans, and the most likely transmission is still from animals to humans, rather than human-to-human. There are two strains, one from western Africa and one from central Africa. The cases in Europe are the western African strain, which causes a milder illness. It's important to emphasise that only a small number of cases have reached Europe, and people are not severely unwell, but scientists are investigating why it seems to be spreading more quickly from human to human than previously. One working theory is that now that COVID-19 restrictions have been lifted, people are travelling more, but have lost some natural immunity to fight viruses during the prolonged period of lockdowns and mask-wearing.