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By: Dawn Berkelaar
Published: 2007/04/20


Introduction

A medicinal plant, Artemisia annua, drew a lot of interest at the ECHO Agriculture Conference in November. For several years, ECHO staff members have followed reports on the use of Artemisia annua to treat malaria. Though artemisia leaves have been used medicinally to reduce fever for 2000 years, we hesitated to write about it, because it is a temperate plant. We were not sure how widely suited it would be to the growing conditions where most members of ECHO’s network are located. For example, in the tropics it tends to flower when the plant is still very short and then dies. This is because the plant flowers when days have less than 13 hours of sunlight.  In the tropics there are many days with less than 13 hours of sunlight!

Figure 1: Seedbank Director Tim Motis stands beside a flourishing artemisia plant on ECHO’s demonstration farm.
Figure 1: Seedbank Director Tim Motis stands beside a flourishing artemisia plant on ECHO’s demonstration farm.

But there is now a variety of artemisia that grows in the tropics despite short days (Figure 1). It also contains higher levels of medicinal compounds like artemisinin. Dr. Hans-Martin Hirt, a keynote conference speaker, obtained permission to purchase patented seed of a special hybrid variety, now called Artemisia annua anamed, which was developed by a pharmaceutical company. Dr. Hirt packages the seed for distribution by community development workers. He has introduced artemisia in many African countries, making its benefits available without the need to purchase pills.

Dr. Hirt works with a unique organization in Germany called anamed (Action for Natural Medicine). He defines “natural medicine” as a philosophy that combines the best of modern medicine (i.e. reliable and accurate prescriptions, given on a scientific basis) and of traditional medicine (i.e. using locally available resources, fitting the local language and culture, and almost always available). Dr. Hirt, who has a Ph. D. in pharmacy, regularly gives seminars to groups in Africa, where he discusses natural medicine with both healers and doctors. These discussions have proved effective in promoting artemisia as a treatment for malaria. 

 

Artemisinin Pills for Malaria Treatment

Artemisinin, a compound found in the artemisia plant, is formulated into pills and sold for treatment of malaria.In the past few years, artemisinin has been recommended by leading donor agencies including UNICEF, the World Bank, and the World Health Organization (WHO). According to an article in the New York Times (May 10, 2004), artemisinin “has no significant side effects, quickly reduces fevers and rapidly lowers blood-parasite levels.”

Artemisinin is often given along with other drugs in an attempt to avoid the development of resistant strains of the malaria-causing plasmodium. For example, Coartem is the trade name for the formulation of artemisinin with another drug called lumefantrine. Coartem is sold by the Swiss drug company Novartis.

However, there are several problems related to the use of artemisinin pills. The pills are not always available, and when they are, they are expensive. Sometimes shopkeepers will sell one or two pills to patients who cannot afford a full course of 12 pills. Many leading malaria experts fear a shortage of artemisia plants from which to extract artemisinin. Also, despite recommendations to the contrary, drug companies often manufacture artemisinin pills as a monotherapy (i.e. as the only treatment), leading to worries that a resistant strain of the plasmodium will develop. And finally, counterfeiting is a problem. The New York Times article (referred to on page 1) mentioned that, in a study of artemisinin drugs in Asia, more than a third were fakes. Some of the pills contained talcum powder instead of artemisinin. More information on the widespread sale of fake artemisinin derivatives is found in a June 2006 article on www.plosmedicine.org.

Artemisia Leaf Tea for Malaria

Treatment Table 1 lists several herbal remedies for malaria. Artemisia is listed last on the table. Please read the footnotes, because some of these remedies should not be used by certain individuals. Also note that papaya leaf tea (of which we have written in the past) is listed on this table.

EDN 95 Table 1

To make artemisia tea, five grams (0.18 ounces) of dried artemisia leaves (about one 35 mm film canister full) are steeped for at least 15 minutes in one liter of boiling hot water (but do not boil the tea!). The patient should drink 250 ml (8.5 oz) of the tea, four times a day, for 7-10 days. Alternatively, 25 grams of fresh leaves can be used instead of the five grams of dried leaves. (Dr. Hirt also recommends drinking lemongrass tea whenever a fever is present.) Artemisia tea is taken for one day initially, and if the fever starts going down, the patient keeps using the tea. If the fever does not start going down, it is most probably not malaria that is causing the symptoms.

For smaller patients, a rule of thumb is to use one gram of artemisia leaf powder in 200 ml of water per 10 kg of body weight per day. So someone who weighs 20 kg would drink tea made from two grams of leaf powder in 400 ml of water. Someone weighing 40 kg would use four grams of leaf powder in 800 ml of water.

If a child is unconscious because of malaria, a double dose of leaf powder with half the volume of water is used as an enema. (i.e. for a 10 kg child, two grams of powder are mixed in 100 ml of water). This is administered in 10 ml increments with 10 ml given every two hours. Once the child becomes conscious, tea is administered orally as usual.

If artemisia tea alone is not effective against malaria (for example for AIDS or cancer patients whose immune systems are already compromised), it can be combined with such antimalarial drugs as fansidar, amodiaquine, etc.

More detailed instructions for the use of artemisia tea (for treatment of malaria and other diseases) are available on anamed’s website (www.anamed.net)..) Anamed has recommended and used the tea to treat malaria with an 80-95% success rate.

[Note: this paragraph is only for those who know a little about chemistry and would like to know how artemisinin works.] Artemisia tea contains at least 46 medicinally active substances that are helpful in fighting malaria. Artemisinin is a “sesquiterpene lactone peroxide.” Dr. Hirt describes its action this way: “Its lethal effect on the plasmodium is due to its two oxygen atoms in the peroxide bond. The plasmodia attack and digest the red blood cells, but because they cannot excrete the iron this accumulates within the plasmodium. When this iron comes into contact with the peroxide in the artemisinin, it breaks the peroxide bond; the oxygen atoms become charged and as such are called free radicals. These free radicals immediately attack the protein in the plasmodium, and the plasmodia are killed.”

Dr. Hirt has commented that the position of the WHO with regards to artemisia is unclear. “On one side, [WHO] gave by its ‘Roll back malaria initiative’ a ‘prize of excellency’ to the anamed group Bukavu for their huge artemisia field, and all the directors never cease to underline the importance of ‘traditional medicine’ for developing countries. On the other side, another representative of the WHO refused to recommend artemisia tea arguing this would be a ‘monotherapy’! In reality, WHO in the year 2004 recommended the ‘monotherapy’ with artemisinin, [but] now warns against it and recommends since 2006 the ‘duplotherapy’ with Coartem.” Dr. Hirt suggests that the tea is already multitherapy because of the other nine antiplasmodial substances that are found in the artemisia tea.

The following question arose at our conference. “Since the plasmodium that causes malaria has developed resistance to other antimalarial medications, might it also develop resistance to artemisia?” If so, that could be devastating, since artemisia may be the world’s last great defense against malaria.

Resistance is certainly a concern with artemisinin pills, since they are often used as a monotherapy. The tea does not seem to pose the same danger of resistance, for three reasons. First, the tea contains less artemisinin (10 mg, compared to 100 mg in an artemisinin pill). Second, the tea also contains other antimalarial compounds. Third, the artemisinin remains in the blood for only eight hours, but it takes 24 hours for the malaria plasmodium to multiply. Despite these facts, it is not recommended to drink artemisia tea continuously as a preventative, ‘just in case.’

After reading a draft of this article, Dr. Hirt commented, “Malaria, AIDS and tuberculosis are responsible for 50% of all deaths in developing countries, according to the WHO. But these three diseases are not isolated. If you suffer from one of them you may easily get infected by another of these three diseases [see the following article]. Artemisinin is not only patented for malaria, but also as a ‘natural antiretroviral’ for AIDS patients. According to anamed, the isolation of artemisinin out of the artemisia leaves is not a ‘purification’, but a ‘poorification’! Artemisia tea itself also improves often drastically the conditions of AIDS patients.” We hope to share more on this topic in an upcoming EDN issue.

Please note: for tourists with no immunity to malaria, anamed strongly recommends that you take a chemical prophylactic when visiting a tropical country, rather than relying only on artemisia tea.

Growing Artemisia

 

 

Artemisia annua seeds are very tiny. Each seed weighs only 0.07 mg. We know from personal experience that artemisia is challenging to grow from the tiny seed, but it can be done. ECHO now has many vigorous plants growing.

To start seeds, line a tray with a towel or cloth, then wet it. Cover with one or two millimeters of sand or soil that has been boiled or baked (to kill any weed seeds or organisms that might infect the tiny plantlets). Sow the seed on top of the sand. The sand helps prevent roots from growing into the cloth, so that tiny plants are easier to transplant later.

The cloth will wick moisture to the seeds. The tray should bekept moist by gently pouring water along the edge(s) of the tray so that it touches the cloth. Do not pour water over the sand and seeds; one drop of water weighs 600 times more than a baby artemisia plant, so you are likely to kill plants if you water that way. Make sure the tray is in full sunlight or is five cm away from a 100-watt bulb. Seeds need the light to trigger germination. Young plants that do not get enough light become tall and thin and flower too early. For the first three to six weeks, you will need to care for the seeds as you would care for a baby—very carefully! (See Figure 2 for diagrams)

[insert figures above] Figure 2: Summary description of how to grow and _prepare artemisia plants to make leaf powder for treatment of malaria. Used with permission from anamed._

A Gardening Hint for planting tiny seeds.

Extremely tiny seeds are difficult to spread evenly on top of the soil. Place some sugar or clean sand in the palm of your hand and mix thoroughly into it the amount of seed you want to end up in the container. Take pinches of sand/sugar and seeds and sprinkle them over the entire surface. It is likely that each pinch will contain about the same number of seeds.

Once an artemisia plant is established, it needs daily access to water or else it will flower prematurely. Established artemisia plants also benefit from lots of nitrogen fertilizer and sunshine. After six to eight months, by which time artemisia plants are often three meters tall, they are ready to be harvested. Cut the stems, remove the leaves, and dry the leaves in full sun.

According to Dr. Hirt, the plant material should be dried until the leaves have a moisture content of 7.5% (i.e. 100 g of leaves do not contain more than 7.5 g of water). When a considerable quantity of leaves dried to this degree are placed in a closed container with a hygrometer (an instrument for measuring relative humidity, available from opticians, electronics stores, or anamed), the relative humidity should read no more than 40%. If you do not have a hygrometer, dry the leaves as you would normally dry herbs for cooking. As long as the leaves are then kept very dry (probably best done in an airtight container), they can be used for up to three years. Harvest the plant as soon as you discover the first flowers, because then the artemisinin content is highest. Once the plant fully flowers, it is already too late to harvest.

Although artemisia seed can be sown throughout the year, you can take advantage of the different seasons. If you live in a dry area, start the seeds in the middle of the dry season. In places with a monsoon climate like Florida, seed should be sown in the middle of the rainy season (but protect it from the rain— remember the small size of seeds). Young seedlings can then be planted out in the dry season when there are fewer plant diseases because it is cooler and less humid. By the start of the next rainy season (when the incidence of malaria rises in endemic areas), leaves will be ready to harvest.

 

Figure 3: An artemisia plant that has flowered and gone to seed. Inset at the right is a picture of seed heads. This plant probably did not receive enough water, so it flowered prematurely.
Figure 3: An artemisia plant that has flowered and gone to seed. Inset at the right is a picture of seed heads. This plant probably did not receive enough water, so it flowered prematurely.
 

Artemisia plants will eventually produce a lot of seed if they are not harvested first (Figure 3). However, since Artemisia annua anamed is a hybrid, planting seed from your own plants will probably result in inferior plants. Such plants will tend to move towards the native form, with shorter stature, fewer leaves, and less quantity of the medicinal compounds.

It is better to regularly take and root cuttings from an established plant. This will produce plants that are identical to the parent plant. It will also eliminate dependence on a continual source of imported seed. But ECHO recommends that if you grow new plants from cuttings, you take the cuttings from many plants. It might be that there is still a lot of variation between plants, even in a field grown from the hybrid seed.

Once an artemisia plant is well-established, it can also be propagated by a method called the “stone method”—place a stone on a branch to hold it to the ground and roots will form along it.

Dr. Hirt commented that artemisia is “easily offended,” especially as a plant gets older. For example, if the plant is about five months old and you forget to water it one day, it will flower and die. The hormone levels inside the plant have changed. Any cuttings planted after the hormone threshold changes will flower right away too. Try to take cuttings each month from a variety of plants (especially young plants). The first cutting can be taken when a plant is 10 cm tall. Using a razor blade to cut, make the cutting 5 cm long. Remove all leaves from the bottom half and plant it in a tray. It is helpful to use a mesh or something similar over the top of the tray, to hold the cuttings upright.

Dr. Hirt sent some artemisia seeds to ECHO in September, for us to propagate before the conference in November. Tim Motis, ECHO Seedbank Director, started the seed.

“The way I propagated our first batch of seed was similar but not identical to Dr. Hirt’s method. I filled a shallow (6 cm/2.4 inch) tray with potting soil and sprinkled a few seeds on the surface of the soil in each of the 50 compartments. The seeds are TINY. Remembering Dr. Hirt’s admonition not to water overhead, I put the plug tray (described above) into a larger tray (a cement mixing tray) that did not have drainage holes. That way, I could fill the larger tray with half an inch of water, enough to allow for water to wick up into the soil in the plug tray. I placed one tray in the screened-in area of the seed bank that receives filtered light (in case the hot Florida sun was too intense). I placed the other tray on a bench outside the seed bank. Seeds germinated fine either way. In fact, I had to thin the seedlings. Before and after germination I made sure the tray of seeds sitting outside was put back indoors if it looked like it might rain. By germinating in a plug tray, I did not need to transplant from a towel into a plug tray, although I could have transplanted thinnings into additional plug trays. Once the seeds had germinated, trays that had been in filtered sunlight were moved to areas with full sun.”

Dr. Hirt planted some seeds at the conference, as a demonstration. Tim wrote, “Dr. Hirt planted seeds in soil on a towel like you mentioned. I kept that tray moist, and the seeds germinated well. I may have waited too long to transplant from the towel into plug trays. The roots had embedded themselves in the towel, and I invariably broke a lot of them as I pulled them out with tweezers. Most of the seedlings survived in the mist house, even with the loss of much of their root system.”

 

Figure 4: An artemisia plant at ECHO. This picture was taken in early February. Seeds were sown in midSeptember on the surface of soil placed in a shallow (6 cm or 2.4 in) tray. Resulting seedlings were transplanted to a four inch pot and then to a raised bed watered with drip irrigation. Photo by Tim Motis.
Figure 4: An artemisia plant at ECHO. This picture was taken in early February. Seeds were sown in midSeptember on the surface of soil placed in a shallow (6 cm or 2.4 in) tray. Resulting seedlings were transplanted to a four inch pot and then to a raised bed watered with drip irrigation. Photo by Tim Motis.

“The seedlings grew very slowly at first. I think I could have sped things up by applying soluble fertilizer sooner than I did. I ended up transplanting from plug trays into four-inch pots without waiting for the seedling roots to fill the cells in the plug trays. I mixed about a teaspoon of six-month slow release fertilizer into the nursery mix with which I filled the four-inch pots. After doing that, growth rate increased significantly. The seedlings shown at conference time in November had been seeded in mid-September. You can see a photo in Figure 4 of one of these plants taken three months later. It was transplanted from a four-inch pot to a raised bed and watered with drip irrigation.”

 

Figure 5: An artemisia cutting that is putting out leaves. Photo by Tim Motis.
Figure 5: An artemisia cutting that is putting out leaves. Photo by Tim Motis.

Dr. Hirt sent some artemisia seeds to ECHO in September, for us to propagate before the conference in November. Tim Motis, ECHO Seedbank Director, started the seed.

“The way I propagated our first batch of seed was similar but not identical to Dr. Hirt’s method. I filled a shallow (6 cm/2.4 inch) tray with potting soil and sprinkled a few seeds on the surface of the soil in each of the 50 compartments. The seeds are TINY. Remembering Dr. Hirt’s admonition not to water overhead, I put the plug tray (described above) into a larger tray (a cement mixing tray) that did not have drainage holes. That way, I could fill the larger tray with half an inch of water, enough to allow for water to wick up into the soil in the plug tray. I placed one tray in the screened-in area of the seed bank that receives filtered light (in case the hot Florida sun was too intense). I placed the other tray on a bench outside the seed bank. Seeds germinated fine either way. In fact, I had to thin the seedlings. Before and after germination I made sure the tray of seeds sitting outside was put back indoors if it looked like it might rain. By germinating in a plug tray, I did not need to transplant from a towel into a plug tray, although I could have transplanted thinnings into additional plug trays. Once the seeds had germinated, trays that had been in filtered sunlight were moved to areas with full sun.”

Dr. Hirt planted some seeds at the conference, as a demonstration. Tim wrote, “Dr. Hirt planted seeds in soil on a towel like you mentioned. I kept that tray moist, and the seeds germinated well. I may have waited too long to transplant from the towel into plug trays. The roots had embedded themselves in the towel, and I invariably broke a lot of them as I pulled them out with tweezers. Most of the seedlings survived in the mist house, even with the loss of much of their root system.”

“The seedlings grew very slowly at first. I think I could have sped things up by applying soluble fertilizer sooner than I did. I ended up transplanting from plug trays into four-inch pots without waiting for the seedling roots to fill the cells in the plug trays. I mixed about a teaspoon of six-month slow release fertilizer into the nursery mix with which I filled the four-inch pots. After doing that, growth rate increased significantly. The seedlings shown at conference time in November had been seeded in mid-September. You can see a photo in Figure 4 of one of these plants taken three months later. It was transplanted from a four-inch pot to a raised bed and watered with drip irrigation.”

Dr. Motis has also propagated artemisia from cuttings (Figure 5). “I have been taking cuttings at various times to make sure I get some that will produce more tall plants. I haven’t had enough cuttings at any particular time to do a whole tray full as Dr. Hirt mentioned. I’ve tried putting some in water in a jar and some in plug trays (with potting soil) in the mist house. Both methods work well. I’ve even tried just planting directly into a planting bed next to drip tape emitters. I’m still monitoring those—we had a frost/freeze, so they were set back, but the cuttings seem to have recovered.”

Dr. Motis added, “Dr. Hirt is right, artemisia likes to be wellsupplied with water and fertilizer. Some artemisia planted in a tire garden have started to flower prematurely. My guess is that the soil in the tire dried out too often. The seedlings established in full sun, with plenty of water and fertilizer, are continuing to grow vegetatively.”

He concluded, “I’ve enjoyed working with artemisia. Yes, it needs regular watering and sunlight, but it grows vigorously and is easy to propagate from cuttings. It has done very well in the cooler fall and spring months. We’ll see what it does in the hot summer.”

We have seen artemisia plants at ECHO set seed (Figure 3). We wonder about its potential for weediness, especially since it and other species in the same genus (Artemisia vulgaris (mugwort) and Artemisia absinthium (absinth wormwood)) are listed as potentially invasive weeds on the USDA Natural Resources Conservation Service Plants database (http://plants.usda.gov/index.html). Dr. Hirt says that anamed has initiated projects in more than 70 countries and has not heard of Artemisia annua anamed becoming a weed problem

Obtaining Artemisia Seeds

Anamed sells a starter kit that contains seeds and instructions on growing artemisia. The seeds have a germination rate of 90%, which drops by approximately 10% per year. To keep the seeds dry, anamed uses a plastic container with seeds kept inside in a separate little bag. In the container, anamed puts rice that has been heated for one hour until it is almost yellow (so that it is extremely dry). The dry rice will absorb moisture within the container. Though the volume of seed inside the starter kit looks small, each kit contains 5000 seeds. Don’t plant all of them at once!

A starter kit costs €110 (110 Euros) plus postage. With it, you can start growing artemisia in many different locations at once. However, only the purchaser of the kit should contact Dr. Hirt with questions. If you need an import permit and phytosanitary certificate to import the seeds, you will need to get the permit from your government and ask Dr. Hirt to enclose the certificate with the package. In addition to seeds, the starter kit contains a packet of artemisia leaves; peat discs for seed sowing; material to help in taking cuttings; several helpful anamed documents; a poster of medicinal plants; and a request for feedback. Ordering information for the starter kit is available from anamed’s website. If you do not have access to the web, contact us and ask for a copy of anamed’s ordering information.

Those that order a starter kit are encouraged to form a network of other individuals/groups who are interested. If you order a kit, you will receive the addresses of other starter kit members in your country.

For More Information

anamed homepage: http://www.anamed.net/ anamed Coordination: Dr Hans-Martin Hirt and Dr Keith Lindsey

Address: Schafweide 77, 71364 Winnenden, Germany

Telephone: +49 7195 910225

Enquiries in English: Keith Lindsey, anamed@t-online.de Enquiries in German or French: Hans-Martin Hirt, anamedhmh@yahoo.de

Follow this link to an article about the World Agroforestry Centre’s work with Artemisia annua anamed in Mozambique: Transformations Quarterly

A short article in Spore 122 [page 9] can be found at: http://spore.cta.int/images/stories/pdf/old/spore122.pdf

Cite as:

Berkelaar, D. 2007. Hope against Malaria. ECHO Development Notes no. 95