Local researchers have presented new evidence showing that the malaria-causing mosquito is no longer sensitive to chemicals used in treating bednets or for indoor spraying.
Mosquitoes in Kenya have developed resistance to the most common chemicals derived from pyrethroids and also against DDT.
Presenting research findings at a national malaria forum in Nairobi on Monday, Dr Charles Mbogo of the Kenya Medical Research Institute (Kemri) said this could be a major blow to the country’s strategy to eradicate malaria by 2017.
“There is especially high DDT resistance in Teso and Busia areas which border Tororo in Uganda which use the chemical in cotton production,” Dr Mbogo told the Nation on the sidelines of the conference.
He said even mosquitoes in other parts of the country had built resistance to DDT, indicating that residues of the chemical, no longer in use in Kenya, were still in the soil.
This new development comes at a time most parts of the country, especially the coastal region, have been recording a significant drop in malaria deaths.
To determine how a chemical-tolerant mosquito will affect the nets as a control tool in the overall malaria reduction strategy, the World Health Organisation has commissioned a new study to be carried out in western Kenya, Benin and Cameroon.
Treated bednets have been one of the most popular and heavily funded malaria control methods in Kenya, consuming up to 60 per cent of funds from the US President’s Malaria Initiative and 40 per cent of the Global Fund malaria package.
Preliminary studies in Benin, Dr Mbogo said, had showed that insecticide resistant mosquitoes could reduce the effectiveness of nets.
“We must not underestimate the impact this new development could have on malaria control, but immediately adopt alternatives such as the use of combination of insecticides and using chemicals on rotational systems.”
It also emerged on Monday that the fight against malaria faced new and untested structures of devolved governments.
According to the World Health Organisation’s malaria adviser in Kenya, Dr Akpaka Kalu, they have been working with the government to develop a malaria control strategy which, if successful, could be exported to other African countries.
Dr Kalu said every county would have a malaria or disease control unit that would not only require autonomy from the central government, but also adequate financial resources.
But it was not all doom and gloom from the scientists with Kemri’s Dr Patricia Njuguna saying a malaria vaccine offering 50 per cent protection for at least one year could be available in four years.