Studies by CSIR researchers and traditional healers on indigenous plants with mosquito repellent properties in the mid-1990s led to the discovery of a novel mosquito repellent. The essential oil of the indigenous plant, Lippia javanica, has more effective repellent properties than similar or comparable commercial products on the market.
A licensing agreement with Zollhaus International(Pty) Ltd has paved the way for marketing of mosquito repellent products, thereby realising the commercial benefit of this local essential oil.
As the most widespread and devastating of tropical diseases, malaria kills one African child every 30 seconds. Sufferers from chronic forms of malaria have diminished quality of life. Together with HIV and tuberculosis, malaria is the major public health challenge undermining development in the poorest countries of the world.
In South Africa, malaria is present in the three northern provinces bordering Mozambique and Swaziland, with seasonal transmission during October to April. Because of their nocturnal feeding habits, malaria transmission by the Anopheles
mosquito occurs primarily between dusk and dawn.
Local populations have traditionally utilised Lippia javanica as a mosquito repellent. Cut branches are wiped on the skin and at the entrances to dwellings, or burnt on an open fire at night. CSIR researchers worked with traditional healers to identify the chemo type of the plant species with superior mosquito repellency properties. Dr Vinesh Maharaj, CSIR natural product chemist, confirms the outcome of this collaboration, “A benefitsharing agreement between the CSIR and the owners of the traditional knowledge resulted in the first benefit payment to traditional healers during July 2012.”
Coming up tops in efficacy
The efficacy (or effectiveness at producing a result) of the essential oil was evaluated at the South African Bureau of Standards (SABS) using olfactometer tests. An olfactometer is a device used to study insect behaviour in the presence of an olfactory stimulus.
Using a standard protocol with the yellow fever mosquito (yellow fever is an acute viralhaemorrhagic disease), it was demonstrated that the CSIR-developed products are significantly more efficient at repelling and expelling mosquitoes when compared to the current products on the market.
Both repellency and expellency are important qualities. Repellency is the ability to prevent mosquitoes from entering an area; expellency is the ability to drive or force mosquitoes from an area.
Producing mosquito repellent candles
According to Dr Marthinus Horak, a key contributor to the CSIR’s enterprise creationfor development activities, the essential step to realising the economic benefit of this discovery was the establishment of a communitybased production process in Limpopo with funding fromthe Department of Science and Technology. This followed the success of the trial plantation of the indigenous plant and the efficacy testing.
The production process starts with cultivation of the plant species on a 20 hectare cultivation site where the mosquito repellent crop is grown. The crop is harvested and distilled in an essential oil distillation factory on the site.
Workers at the factory of 650 m2 in Giyani (Limpopo) have acquired the production technology and skills required to manufacture the mosquito repellent candles on-site. The factory contains equipment to formulate the active ingredients of the candles, and manufacture and package up to 400 000 candles per year. The project provides employment for more than 20 people in rural communities.
As its first step, the CSIR filed a South African patent on the use of extracts and chemical substances derived from the
plant as mosquito repellents. Brian Mphahlele, CSIR commercialisation manager, confirms that this gives the CSIR the right to stop anyone from making unauthorised use of the intellectual property.
He took the lead in negotiating commercial terms for a licence agreement with Zollhaus to formulate the patented extract into mosquito repellent/expellent products for distribution and sale to local and export markets. All royalties negotiated under the licence will be paid in full to the owners of traditional knowledge. Through this licence, the CSIR secured demand for the oil produced by the local community and in the process helped generate economic activity for the local
community. This falls squarely within the CSIR’s mandate – bettering the lives of ordinary South Africans through research and development. Mphahlele explains, “Zollhaus’s expertise lies in developing and positioning products in key
Based on its market findings, Zollhaus developed a range of fragranced candles that effectively repel mosquitoes. Additional SABS tests indicate that the improved product has fly-repellent properties.
Zollhaus has taken some additional steps to firm up marketing prospects. The registration of the mosquito repellent candle in terms of Act 36 of 1947 allows the sales of candles to the public. Zollhaus also successfully negotiated sales with South African chains stores and the product is currently available under the brand name ‘Fever-Tree’ in more than 200 South African stores.
What lies at the heart of the success of South Africa’s ‘homegrown’ mosquito repellent is a winning technology recipe in which several players at the CSIR fulfilled key roles: natural product chemists working with owners of traditional knowledge; enterprise creation experts giving guidance; and technology transfer experts who recognise the market potential of this product.
Facts about malaria
- Malaria transmission is caused by the bite of a female Anopheles mosquito carrying the Plasmodium falciparum parasite.
- Worldwide, mosquitoes transmit disease to more than 700 million people. Annually, it leads to more than 300 million acute illnesses and claims the lives of at least one million people.
- Ninety percent of deaths due to malaria occur in Africa, with the majority of its victims children under the age of five.