Washington D.C : Oils from garlic and several other common herbs and medicinal plants show strong activity against the bacterium that causes Lyme disease.
According to a study by researchers at Johns Hopkins Bloomberg School of Public Health, these oils may be especially useful in alleviating Lyme symptoms that persist despite standard antibiotic treatment.
The study, published in the Journal of Antibiotics, included lab-dish tests of 35 essential oils that are pressed from plants or their fruits and contain the plant's fragrance, or essence.'
The researchers found that 10 of these, including oils from cinnamon bark, garlic cloves, myrrh trees, cumin seeds, thyme leaves, and allspice berries showed strong killing activity against dormant and slow-growing 'persister' forms of the Lyme disease bacterium.
"We found that these essential oils were even better at killing the 'persister' forms of Lyme bacteria than standard Lyme antibiotics," said study's senior author Ying Zhang.
Standard treatment with doxycycline or an alternative antibiotic for a few weeks usually clears the infection and resolves symptoms. However, about 10 to 20 per cent of patients report persistent symptoms including fatigue and joint pain, often termed 'persistent Lyme infection' or 'post-treatment Lyme disease syndrome' (PTLDS) that in some cases can last for months or years.
The cause of this lingering syndrome isn't known. But it is known that cultures of Lyme disease bacteria, Borrelia burgdorferi, can enter a stationary phase in which many of the cells divide slowly or not at all. The slow-dividing or dormant cells are 'persister' cells, which can form naturally under nutrient starvation or stress conditions, and are more resistant to antibiotics.