Can Malaria be Defeated?
MALARIA IS A PARASITIC DISEASE THAT INVOLVES HIGH FEVERS, SHAKING CHILLS, FLU-LIKE SYMPTOMS, AND ANEMIA.
Malaria is caused by a parasite that is passed from one human to another by the bite of infected Anopheles mosquitoes. After infection, the parasites (called sporozoites) travel through the bloodstream to the liver, where they mature and release another form, the merozoites. The parasites enter the bloodstream and infect red blood cells.
World Health Organization says: "Malaria will strike more than 200 million people this year and will kill nearly half a million”. Although the disease can be treated, in some parts of the Africa the medicines needed are often unavailable. What is worse, the parasite that causes malaria is becoming more and more resistant to the drugs we have to fight it.
That’s why several research groups are working on genetic modifications to mosquitoes that would prevent them from spreading the parasite. The University of California, Irvine, has created a mosquito that not only doesn’t transmit malaria but also passes on this trait to 99.5 percent of its offspring
“That’s certainly an achievement” says Anthony James, whose team used a gene-editing technique called CRISPR to insert two genes into the insect’s genome to confer malarial resistance. “Given the high rate of inheritability, the resistance would theoretically spread quickly throughout a population once it has been introduced”, James says.
The UC Irvine team worked on the genome of Anopheles Stephensi Mosquitoes, which are a main vector of malaria in India, where there are more than 500 deaths yearly. This technique of introducing malaria resistance used by the UC Irvine team was first demonstrated in fruit flies, after the team successfully applied the same method to mosquitos. Older gene-editing techniques would have taken much longer to fine-tune for different animals.
The two genes James’s team has introduced are modified mouse immune genes, which bind to the malaria parasites and prevent them from recognizing their host and moving around in the mosquito’s body. “You can think of it as [being] blinded,” James says. As a result, the parasite cannot get into the animal’s salivary gland and, therefore, doesn’t make it into humans when the mosquitoes bite.
The innovation needs to be tweaked slightly before being applied in the field and introducing genetically modified organisms into the wild would require regulatory approval from foreign countries where malaria is endemic. But he’s hopeful it could be introduced sometime in the next several years.
James says more research needs to be done on likely long-term effects of the modification before using it in the real world.