by Tracey Hogan
You might have tasted the delight of the lemon myrtle, or Backhousia citriodora, in an Aussie bush tucker rub or spice mix. It's incredibly 'tangy', and is often described as 'more lemony than lemon'. What you can taste is the citral, a component of lemon myrtle with promising applications.
In a clinical trial published back in 2003, the application of lemon myrtle essential oil had a 90% success rate for the treatment of the virus Molluscum contagiosum. This virus usually affects children, but can also be sexually transmitted in adults. It causes flesh coloured, dome-shaped pearly papules on the skin, usually with a little indent in the middle. It's from the pox strain of viruses and is mainly spread by skin to skin contact. The trial was conducted with 31 children between 2 and 6 years of age (the average age was 4), and there was a greater than 90% reduction in 9 out of the 16 children treated with lemon myrtle essential oil.
Treatment for Molluscum contagiosum can otherwise be invasive, with tissue scraping or freezing, so lemon myrtle could be considered a less invasive way to reduce the size and spread. Spontaneous resolution can occur, but can take between 12 and 30 months! From the study they made the hypothesis that it may be more than the citral component of the lemon myrtle at work here to inhibit this virus, and further work would be needed. It does provide a much less painful alternative to treat this virus, which can occur on the face, armpits, and travel more extensively over the body.
Lemon myrtle, ironically, is fighting a battle with destruction due to an introduced 'rust'. Myrtle rust was first found on a property on the New South Wales central coast in April, 2010. It belongs to fungi known as 'guava rust complex'. It had never been found in Australia before, but is native to South America, Mexico, and in the United States (Florida and Hawaii). Because the fungi produce microscopic spores easily carried by the wind, it may have entered Australia on plants or other goods being shipped around the globe, or it could have even hitched a ride on someone's clothing.
Myrtle rust is a serious pathogen that may damage not only the lemon myrtle industry, but also have an impact on the tea tree oil industry, as these plants have also been affected in some areas. Some eucalypt species have also been impacted. When the plants are severely infected, young plants and new growth become stunted and, in the worse cases, die.
There is ongoing work happening to find a solution to this to minimise the impact, not only for the essential oils industry, but for the Australian environment as a whole. Growers are closely monitoring the severity of the impact. Fungicides have been trialed but are an unfavourable solution. One of the attractions for growing lemon myrtle was that it didn't require pesticides or fungicides.
It's now spread to some commercial plant nurseries, and large areas of bushland. Further spread of the disease is anticipated. The Commonwealth of Australia has chaired a Myrtle rust co-ordination group. It will co-ordinate ongoing actions to mitigate the impact of the Myrtle rust on our natural environment.
It's potential application as an anti-viral and anti-bacterial may be short-lived if we don't find a solution to this 'rust'. It's not only the complementary medicine industry that will see the ripple effect of this 'rust' that has travelled across the globe, as the long-term environmental impact is yet to be determined.
Tracey Hogan is a Sydney naturopath, nutritionist, herbalist and homoeopath with 18 years' experience in the industry. She regularly writes on complementary health topics.