Open the door to a vault-like room at the University of California, Davis, and the cool sterility of a laboratory gives way to the sticky heat of the tropics, with thousands of mosquitoes buzzing in cages and feasting on blood.
Here in the university’s medical-sciences complex, researchers are studying mosquitoes that they have genetically altered to resist the parasite that causes malaria.
In other words, malaria-proof mosquitoes.
Now the goal is to make the altered mosquitoes hardier than native varieties, which they could someday supplant in nature throughout the world.
“Our hope is to release them and drive the gene through the population,” said professor Shirley Luckhart, a leader in the joint effort between scientists at UC Davis and the University of Arizona.
Time magazine recently named their development of malaria-proof mosquitoes as one of the 50 best inventions of 2010 and gave it the No. 1 spot in the health-and-medicine category.
Why? Because malaria, a mosquito-borne disease, sickens an estimated quarter-billion people annually in the world’s tropical and subtropical regions and kills one million a year, mostly children in Africa.
The World Health Organization estimates that a child dies every 45 seconds from malaria in Africa, and the disease accounts for 20 per cent of all childhood deaths on the continent.
But malaria’s effects extend beyond human illness and death. The disease is the scourge of developing nations, bringing work and education to a standstill each rainy season.
Luckhart has travelled to Africa for research and witnessed malaria’s devastation.
When infected, she said, “You can’t work. You can’t go to school. You can’t take care of your family.”
That, in turn, has a big impact on national economies. “Malaria can decrease gross domestic product by as much as 1.3 percent in countries with high disease rates,” WHO says in its online fact sheet.
At UC Davis, the scientists’ work is driven by the idea that the health of millions and the economies of nations can be affected by the infinitesimally small workings of an insect’s innards.
The project, funded by the National Institutes of Health, began in 2008, with scientists at UC Davis and Arizona collaborating.
The Arizona team, led by professor Michael Riehle, genetically engineered the mosquitoes.
The scientists took an existing gene and amped it up to stimulate production of a key protein that disrupts development of malaria-causing Plasmodium parasites.
UC Davis researchers then conducted infection studies, feeding the altered insects malaria-tainted blood and measuring the results. They found either a vastly decreased number of parasites in the altered mosquitoes or none at all.
They’re still working to understand why the mosquitoes are so resistant to infection.
“What we don’t understand is why the parasite doesn’t survive,” Luckhart said. “Is it killed, or does it not survive because the conditions aren’t right for its development?”
She said the genetically engineered insects will not be released until much more is known.
“We’re not going to introduce something into natural conditions until we fully understand how it works,” she said. “We also want to increase the chances of success.”