Patrick Engeu Ogwang grew up in the small town of Soroti, in eastern Uganda, where malaria was (and still is) endemic. He, like most of the townspeople, was accustomed to malaria attacks, and to the skills of the local people in treating it at home.
"When one of us had malaria," he said, "people would go pick some leaves and roots. They'd dry the plants, pound them, boil them, cool them, dry them again. They'd mix up the powder with water in the bathtub and then filter it. They used many plants for malaria – not just artemesia. You'd drink this mix three times a day, and after two days the malaria would be gone. About 60% of Ugandans use these plants for many ailments."
Patrick's interest in plants stayed with him through secondary school and then he won a government scholarship to attend Makerere. He found a job at the Ministry of Health, where he was able to study natural products. He was not surprised when his office received a call for advice about a particular malaria remedy. The callers were concerned about any side effects, and whether the amount they were taking would really help. That much was not surprising; the lab had heard such requests before. But Patrick was surprised by the details.
"This was a group of about 1,000 workers at a flower farm in Entebbe," he recalled. "There was a lot of malaria around. The workers had heard about artemesia and decided to try it. The difference was, they didn't just take it when they got sick, which is how everyone uses it. They made it into a tea and drank it every day to prevent malaria, not to cure it. We'd never heard of anyone using artemesia as a preventative."
Patrick and his colleagues got started by dividing the workers into two study groups – 120 tea drinkers, and 120 controls who abstained. He documented cases of malaria in each group, and found encouraging results. According to preliminary findings, those drinking the tea gained a 35-60% protective effect over those not drinking it. The protective effect was higher when the malaria incidence was most severe, after heavy rains.
With the help of AFNNET, Patrick and co-workers will follow the flower workers for a year, trying to answer some of the many questions raised by this discovery: how long will the drug be stable; how long does protection last; can an additive such as avocado improve the bitter taste without altering its efficacy?
Most important, says Patrick, is to isolate the components chiefly responsible for the protective effect. An interesting aspect of the mystery is the artemesia itself. The familiar therapeutic fraction is called artemesinin, which is most active in the bloodstream for only about an hour, and remains in decreasing amounts for only about 6 hours. It is highly unlikely that artemesinin is responsible for prophylaxis. So much chemical detective work remains to be done. "We'll keep looking for the flavenoids responsible for this," he said. "We need to know that to bring quality control and to improve the activity."