By Tsumbedzo Ramalevha, Intern & Dr Dave Thompson, Scientist, SAEON Ndlovu Node

Artemisia afra – known as lenganauMhlonyanewilde als and African wormwood in South Africa – has been used as a traditional cure for flu-related illnesses such as colds, fever, coughs and headaches by generations of South Africans. 

This species, and others in the genus, are some of the oldest and best-known medicinal plants globally and are still used in South Africa by people of all cultures. Dried material (Fig. 1) for making herbal infusions as well as ready-to-drink tonics can be purchased from street vendors, traditional healers and large online commercial retailers alike.

Figure 1. Artemisia afra leaf and flower material can be sold unprocessed, or simply dried and milled. However, a large range of teas, tonics, capsules and oils is readily available through traditional and commercial outlets (Photo: sellsa.co.za/african-wormwood-250g-artemesia-afra)
Figure 2A. Lengana is a shrub found in grasslands and forest margins through much of South Africa. (Photo credit: phytoalchemy.co.za)
Figure 2B. The species recovers rapidly from fire disturbance, producing new stems from underground woody rootstocks (right). However, monitoring suggests the species is drought-intolerant (Photo credit: Sylvie Kremer-Kӧhne)

International spotlight on lengana 

As the coronavirus pandemic gripped Africa earlier this year, lengana was thrust into the spotlight following claims by the Madagascan president that a herbal infusion based on a closely related species – Artemisia annua (mugwood, sweet wormwood), which has its origins in Asia – was a cure-all remedy and a preventative against Covid-19 infection.

Following these claims, many countries particularly in central and east Africa, imported the brew, marketed as Covid-Organics, for local and wide-scale distribution. However, at the same time the World Health Organization (WHO) and the African Centre for Disease Control (Africa CDC) cautioned that no clinical evidence existed in support of the herb as an effective cure or as a preventative against Covid-19…