Posted 7:49 AM
by Mary
Breakthrough in fight against malaria
Steve Connor, Science Editor
The fight against malaria has entered a new phase with an insecticide specifically targeted at older mosquitoes, which scientists believe will be more effective than existing pesticides.
Most malaria infections, which kill about one million people a year, result from humans being bitten by older mosquitoes. Yet existing insecticides kill mosquitoes of all ages and, as a result, the chemicals soon become ineffective because the insects develop pesticide resistance. Killing the younger creatures encourages the development of that resistance.
Researchers have begun the development of slow-acting pesticides that kill mosquitoes only after they have reached a certain age in their lifecycle, when they are most likely to transmit the malaria parasite to human hosts.
"If we killed only older mosquitoes we could control malaria and solve the problem of resistant mosquitoes," said Andrew Read, professor of biology and entomology at Penn State University. "It is one of the great ironies of malaria. Most mosquitoes do not live long enough to transmit the disease. To stop malaria, we need to kill only the old mosquitoes."
Female mosquitoes transmit malaria when they feed on blood, which they need to make their eggs. After they pick up a malarial parasite, it takes between 10 and 14 days, or two to six cycles of egg production, for the parasite to migrate to the insect's salivary glands, from where the malarial parasite can be transmitted.
Labels: Malaria, MDGs
