Your skin is your largest organ – but it often gets neglected. Identify and treat the mystery marks that might appear when you're travelling with our guide
What it looks like: Raised red area that usually itches a lot. It may be a single lump or one of several. Often first noticed the morning after enjoying a warm, scented evening outside in hotter climates.
What could it be? Most likely a mosquito bite. If the bumps are in lines they could be due to a flea in your bed. Bed-bug bites often wake you up because they hurt.
What to do: Consider if you’re in a malarious region (if so, you should be taking antimalarials already) and plan bite avoidance for the next evening. If bites are in lines, spread your bedding or sleeping bag out in the sun – this will drive away any fleas and bed bugs. Antihistamine tablets or a steroid ointment will help stop the irritating itch.
What it looks like: Puncture marks or lacerations in your skin after a swim.
What could it be? It’s easy to sustain inexplicable injuries while swimming. A double puncture mark can make you think you’ve received a sea-snake bite, but usually it’s a scratch from a sunken object. Some swimmers imagine they’ve been infected with a slow-acting venom from a sea creature; fortunately most wounds that need medical attention hurt when inflicted.
What to do: Seek medical assessment if you think a sea snake (or krait) has bitten you – they rarely bite, but their bites are painless, the venom slow acting. Other scratches and scrapes should be cleaned and dressed in the usual way.
What it looks like: A dark blob attached to your skin.
What could it be? If the ‘mole’ has appeared suddenly, it’s likely to be a feeding tick, which should be removed carefully and the wound flooded with spirit alcohol. If it is indeed a mole that seems to have rapidly increased in size, it’s probably the result of sunburn, or you may have caught the mole and made it bleed inside.
What to do: If you’ve removed the tick promptly and completely, you can usually forget about it unless you become unwell or notice a red ring around the bite – then you need to see a doctor. In the case of real moles, it’s common for them to become inflamed. This is rarely a sign of trouble; however, such moles need checking by a doctor.
What it looks like: Blotches on various parts of the body. Might be tiny or large/ bumpy; some you can feel, some are deep in the skin.
What could it be? Many infections and allergic reactions cause hard to define rashes.
What to do: If you have a fever over 38.5°C and the rash doesn’t blanche when pressed, see a doctor fast – in case it’s meningococcal disease. If you feel well but are itching, get cool and try an antihistamine tablet.
What it looks like: A graze or bleeding wound on your body.
What could it be? You’ve cut your skin on something sharp. Yellow/green oozing some days after the injury or spreading redness suggest infection.
What to do: The first challenge is to clean the area and remove any grit or debris, and then stop the bleeding. Ensure the wound is thoroughly cleaned by washing (scrubbing if necessary) under a running tap. Stop any bleeding by applying pressure with a clean dressing or cloth. Change dressings daily unless you have managed to get someone to put on a good, First World-type iodine dressing. Look out for spreading redness and fever – indicative of infection, which will require antibiotic treatment.
What it looks like: Purplish areas of skin, often where you’ve bashed it. Old bruises morph through a range of colours and migrate under gravity. Touching a bruise (even one that has moved away from the original site of injury) is tender.
What could it be? A normal response to injury, and a side-effect of being more active and in an environment where unexpected objects leap out and assault you. Easy bruising happens in people taking aspirin.
What to do: Apply a warm poultice (run a face cloth under a hot tap) or forget about it. Easy bruising can be a sign of a more serious condition but this is enormously rare. See a doctor if you are concerned.
What it looks like: A raised, red tender area that exudes pus; could be a lone sore or one of many.
What could it be? If the weeping sore is a singleton and there is no spreading redness this is impetigo, which is only a local infection. If the sores are widespread then you should be concerned that the infection is spreading through the bloodstream.
What to do: Clean up any weeping sore with a good drying antiseptic such as diluted iodine (or Savlon Dry); widespread sores will need a course of antibiotics by mouth for a week. Applying Germolene creams and the like won’t help – and could even make things worse.
What it looks like: Red-raw area of skin that usually oozes straw-coloured fluid.
What could it be? Burn-like lesions can appear on the skin due to bacterial infection, when there is often spontaneous blistering too, as well as following excessive exposure to the sun.
What to do: If it is a small area of burn or scald, keep it clean and covered; if it’s a large area (eg half a limb), an area where function is important (eg the hand) or the skin looks scalded but hasn’t been, see a doctor promptly. Meanwhile, drink plenty of fluids – it’s important to stay hydrated.
What it looks like: An old mosquito bite that appears to almost heal and then breaks down, oozes a little bit, crusts over, gets almost better and then turns worse again. The crusted lump tends not to itch much and isn’t usually painful.
What could it be? Possibly a tropical sore due to leishmania parasites, especially if you’ve been to tropical Latin America or the Middle East. If you are over 40 this is most likely to be a rodent ulcer – a mild form of skin cancer.
What to do: See a doctor, who can do a biopsy. This is not urgent – on a trip of, say, a month duration it can wait until you come home. Tell the doctor about any exotic trips you’ve been on in the previous couple of years.
Top tip: If you can’t get hold of an official antiseptic, use some type of spirit alcohol: pisco, raksi, whisky, gin, rum... It’s an excellent substitute – and you can drink the leftovers!
Keep up-to-date with the world's travel health news with our weekly posts... More
Check out all articles from Dr Jane Wilson-Howarth for more health advice... More
6 tips for travel health happiness | Inspire me... More
Health after travel: keep safe once you've returned | Advice... More
Health: fact or fiction | Dr Jane sorts out the old wives' tales of travel | Advice... More
