It's an age-old first aid adage that many swear by: It's important to let a wound breathe. 

But now, a TV doctor has revealed 'airing out' a cut rather than covering it with a plaster can not only prevent healing, but also result in potentially serious infections and scarring.   

Dr Zoe Williams, an NHS GP working in London and resident doctor for ITV's This Morning, warned forgoing plasters for even a short while is one of the biggest mistakes you can make.

Even tiny cuts can get infected with germs and bacteria during everyday activities like showering or swimming, she said in a fresh alert.

In worst-case scenarios, these infections can spread to other areas of the body, and even trigger life-threatening sepsis.

The best way to treat a wound is to apply a plaster, which ensures it has a clean and moist environment, she advised.

'This is not only important for rapid healing, but also to minimise scarring.'

But she added that it is important to clean a graze before applying a plaster to the wound.

This can be done by washing your hands, rinsing the wound with clean water or wound spray and gently drying it with a clean cloth first.

Dr Williams' advice comes as a poll of 2,000 adults by the plaster company Elastoplast found 42 per cent believed the myth letting a wound breath is the best way for it to heal.

Only 14 per cent of respondents knew that keeping a cut moist would help it to repair faster.

The poll also found a third of the adults had touched a wound before washing the hands. 

While it isn't clear if it is because of how they treated their wounds, the adults reported scarring (19 per cent), infections (17 per cent) and swelling (16 per cent). 

The doctor recommended hydrocolloid plasters which can help the cut 'maintain a moist environment' and offer pain relief and longer wear.

But if you have an allergy to plasters you can still cover up your wound with dressing like a bandage or pad, which can be bought from pharmacies, she added.

The most common ways adults got cuts, grazes and injuries were indoor DIY work (39 per cent), hiking or walking (27 per cent), playing team sports (23 per cent) and cycling or mountain (19 per cent), the survey revealed.