Picnics in a countryside strewn with bramble thickets and ridden with wasps and other insects soon won’t be complete without tea tree oil, an antiseptic, fungicidal and insect-repellent oil that also has antideodorant properties. Tea tree oil has been used for medicinal purposes by Australian Aborigines since the time that mammoths ranged over Norfolk and the northern hemisphere.

Its fame has now spread throughout the world. Tea tree oil is a natural herbal remedy that stands comparison with topical antimicrobals and antiseptics. It is as popular with the former nurse taking her children out for the day as it is with New-Age woman who wants a deodorant that will banish thrush, fungi and body odour without using products containing aluminium.

The Aborigines have been using the oil obtained from the tea tree, a small 15ft (4m) tree or large shrub indigenous to the continent, to treat insect bites and wounds and to repel insects for around 40,000 years. Captain Cook refers to it in 1777. And 150 years later tea tree oil had an equally distinguished campaign record: during the Second World War the Australian Government followed the example set by the country’s original inhabitants, and commandeered stocks of tea tree oil for the first-aid kits of soldiers serving in the Pacific.

Production declined after the war when other antiseptics became available. The fashion for natural medicinal products, its effectiveness and the greater awareness of tea tree oil as a result of international exotic travel has resulted in there now being 150 Australian companies producing it. These work together as a co-operative. Efforts were made to prevent the tea tree oil tree being planted away from its natural habitat in Australia, but it has been smuggled out and is now being grown in Africa, Indonesia, China and India.

There are several species of tea tree. The best for the production of the oil is Melaleuca alternifolia. The essential oils are extracted from the leaves of the plant by steam distillation. The process removes other chemicals and thereby creates a purer oil. The therapeutic value is thought to be dependent on its terpinen-4-ol content (a component of the seed oil). Australians claim that the oil derived from trees grown in their original habitat has a higher content of terpinen than that produced in other countries, and that non-Australian oils are not of the same consistent quality.

A randomised control trial of tea tree topical oil preparations comparing it with the standard regime was carried out at the Royal Hampshire County Hospital. The trial measured the relative ability of the two regimes to clear MRSA (the antibiotic resistant bacteria found in hospitals) colonisation from various sites. The tea tree oil compared favourably to modern pharmaceutical skin preparations.

The oil was slightly less effective in clearing noses and throats, appreciably more effective in clearing armpits, groins and perhaps surprisingly skin sores of the potentially lethal Staphylococcus aureus. The results were published in the Journal of Hospital Infection.

Thursday Plantation tea tree oil, one of the Australian brands available in the larger British chemists and Holland & Barrett, is marketed as an oil, a lotion, a deodorant or foot spray. It has been used with success to treat various skin diseases causing irritation in dogs, but is not recommended for cats, which react unfavourably to it.

Most households won’t be using tea tree oil to eradicate MRSA infections but are more likely to employ it as an insect repellent, a foot spray that is both deodorising and antifungal, or to treat the inevitable cuts and insect bites and stings that affect families in Sussex as well as Sydney.