Uganda: Mosquito-Killing Weed Discovered
31 July 2007
Posted to the web 1 August 2007
Aidah Nanyonjo
Kampala
AS the use of Dichloro-Diphenyl-Trichloroethane (DDT) still faces resistance from the environmentalists, researchers have discovered a weed called Polygonum Senegalese, commonly known as omufumbagyesi in Runyakitara, that can be used to spray and kill mosquitoes.
According to Prof Jacob Midiwo, the executive secretary of Natural Product Research Network for Eastern and Central Africa (Napreca), the weed can be used to spray the larvae in breeding places.
"Polygonum Senegalese can work as a substitute to DDT in the control of malaria, since it tackles the mosquito problem right from the first stages of the mosquito's lifecycle. Its toxicity has not been realised," Midiwo says.
Polygonum Senegalese is a weed that grows mostly in the highlands of the East African region. In Uganda, it can be found around the Rwenzori and Elgon mountains. The weed can be planted to enable it multiply and supply the required demand.
According to the research, the leaves of Polygonum Senegalese contain compounds that kill the larvae when they consume it.
"The leaves of the weed are crushed and mixed with water. The water is then poured in breeding places like ponds. When larvae consumes it, it dies," Midiwo said.
While presenting a paper during a symposium on drug discovery at Hotel Africana recently, Midiwo said research has been carried out on over 60 plant species to get an appropriate alternative to DDT, which is claimed to be toxic to the environment.
The symposium was intended to help generate knowledge and skills on various plants, which could be used in product development.
Although the weed can effectively kill the larvae, other experiments are being carried out to establish the side-effects of the weed on other aquatic animals.
However, Dr Christine Kabuye from the Department of Botany, Makerere University, doubted whether the weed could totally replace DDT. This is because each handles the mosquito problem at a different level.
"DDT targets living mosquitoes so Polygonum Senegalese cannot be a substitute. However, we all need something, which is degradable and non-toxic," Kabuye said in protest.
Meanwhile, other malaria control research measures are being carried out to eradicate the parasite. This follows the high resistance development to drugs and chemicals by the parasite and the vector. Erythrina abyssinica, known as ejirikiti in Luganda, ekiko in Runyankole-Rukiga, have shown potent anti-plasmodial activities.
"If you do not want to fall sick anymore, use the extracts of Erythrina abyssinica," said Dr Grace Nambatya, of the health ministry's chemotheraptic department.
Dr Stephen Mallinga, the health minister challenged scientists to take advantage of the region's biodiversity and actively engage in innovative research that can lead to drug development. "Since Uganda has vast resources for research activities, we want to hear news of drug discoveries emanating from our scientists here."
31 July 2007
Posted to the web 1 August 2007
Aidah Nanyonjo
Kampala
AS the use of Dichloro-Diphenyl-Trichloroethane (DDT) still faces resistance from the environmentalists, researchers have discovered a weed called Polygonum Senegalese, commonly known as omufumbagyesi in Runyakitara, that can be used to spray and kill mosquitoes.
According to Prof Jacob Midiwo, the executive secretary of Natural Product Research Network for Eastern and Central Africa (Napreca), the weed can be used to spray the larvae in breeding places.
"Polygonum Senegalese can work as a substitute to DDT in the control of malaria, since it tackles the mosquito problem right from the first stages of the mosquito's lifecycle. Its toxicity has not been realised," Midiwo says.
Polygonum Senegalese is a weed that grows mostly in the highlands of the East African region. In Uganda, it can be found around the Rwenzori and Elgon mountains. The weed can be planted to enable it multiply and supply the required demand.
According to the research, the leaves of Polygonum Senegalese contain compounds that kill the larvae when they consume it.
"The leaves of the weed are crushed and mixed with water. The water is then poured in breeding places like ponds. When larvae consumes it, it dies," Midiwo said.
While presenting a paper during a symposium on drug discovery at Hotel Africana recently, Midiwo said research has been carried out on over 60 plant species to get an appropriate alternative to DDT, which is claimed to be toxic to the environment.
The symposium was intended to help generate knowledge and skills on various plants, which could be used in product development.
Although the weed can effectively kill the larvae, other experiments are being carried out to establish the side-effects of the weed on other aquatic animals.
However, Dr Christine Kabuye from the Department of Botany, Makerere University, doubted whether the weed could totally replace DDT. This is because each handles the mosquito problem at a different level.
"DDT targets living mosquitoes so Polygonum Senegalese cannot be a substitute. However, we all need something, which is degradable and non-toxic," Kabuye said in protest.
Meanwhile, other malaria control research measures are being carried out to eradicate the parasite. This follows the high resistance development to drugs and chemicals by the parasite and the vector. Erythrina abyssinica, known as ejirikiti in Luganda, ekiko in Runyankole-Rukiga, have shown potent anti-plasmodial activities.
"If you do not want to fall sick anymore, use the extracts of Erythrina abyssinica," said Dr Grace Nambatya, of the health ministry's chemotheraptic department.
Dr Stephen Mallinga, the health minister challenged scientists to take advantage of the region's biodiversity and actively engage in innovative research that can lead to drug development. "Since Uganda has vast resources for research activities, we want to hear news of drug discoveries emanating from our scientists here."