NAIROBI, Kenya, Nov 2 – The World Health Organisation (WHO) has raised the alarm over a new trend of malaria vector resistance to Insecticide Treated Nets (ITN).
WHO Coordinator for Vector Control and Prevention- Global Malaria Programme, Dr Jonathan Lines said some vector resistance had been noted in Eastern Uganda on the Uganda-Kenya border, Benin and Cameroon.
“There are just signs that when you expose the mosquitoes, they are not dying as they should but we are not yet sure whether this means treated mosquito nets will not work in that area,” Dr Lines said.
He said although there was no clear case of control failure yet, scientists had been monitoring the bits of resistance.
“We have known one form of pyrathroid resistance for about nine years, one in Western Kenya (of a not very strong kind) and another in West Africa and we have been tracking that,” he said.
Addressing a press conference during the week-long Pan African Malaria Conference, Dr Lines said that form of resistance was known as KDR which was very easy to detect with simple DNA methods and it had reached high frequency in some places.
“We seem to be able to continue to do effective vector control. I think perhaps we have not been watching carefully enough and behind that there are new mechanisms of resistance, called metabolic mechanisms of resistance which means there are enzymes inside the tissue of the insect which break down the insecticide before it can get to its target inside the body of the insect,” he explained.
He said these mechanisms were much harder to study at the genetic levels and to track in individual insects and scientists were now developing simpler methods of tracking them on a larger scale.
He blamed the new resistance on lack of routine resistance monitoring as it should have been although it was known in principal that it was good practice to do through resistance testing before, during and after any insecticidal campaign.
Dr Line however said extensive coverage with long lasting Insecticide Treated Nets and indoor residual spraying had significantly reduced malaria morbidity and mortality in Africa.
At a separate press briefing at the same conference, the high cost of the internationally recommended anti-malarial drugs, Artemesinin Based Combination therapy, ACT’s was termed as the greatest barrier to access of the right treatment for patients in Sub-Saharan Africa.
Population Service International, Vice President Malaria Control and Child Survival, Dr Desmond Chavasse warned that this could threaten the fight against malaria which was still a leading killer disease especially for children under five years.
A 2008 World Malaria Report indicated that 97 percent of people in sub-saharan Africa didn’t access the right malaria treatment within the first 24 hours of illness because of the high cost and unavailability.
“What we have found is that mothers of children with fever primarily go to shops rather than government health facilities when they are seeking treatment and here they generally find that ACT’s are not available and if they are they simply cannot afford them anyway,” Dr Chavasse said.
“As a result of this, most of Africa’s children presenting with malaria symptoms are either not being treated at all or are being treated with ineffective drugs,” he added.
Clinton Foundation Director, Malaria Control Team, Oliver Sabot said this had made it necessary to subsidise the ACT’s to make them affordable and remove the status quo.
“If we are to break the barrier and dramatically scale up access to these drugs to the 80 percent global target that we have set, we need to find ways to get ACT’s out through the private channels and it is basically the global malaria community to apply subsidy for the price of ACT’s at the global level to drop the price by 95 percent,” he said.
A World Health Organisation Medical Officer, Global Malaria Programme, Dr Peter Olamese said the resistance of Insecticide treated mosquito nets and the recommended drugs could set back all the gains made on malaria control.
In February this year, Public Health Minister Beth Mugo said Kenya was among 11 other nations that had been selected to benefit from subsidised anti malarial medicine through development partners.
She said this would bring down the cost of ACT’s from the current Sh400 to Sh20.