The $10.2 million grant, awarded by Open Philanthropy, will go toward research aiming to find a way to eliminate malaria from Africa
By SONORA SLATER — science@theaggie.org
Malaria, a mosquito-borne infectious disease, was discovered in 1880, and has remained widespread in tropical regions around the equator including parts of Africa, Asia and Latin America, resulting in thousands of deaths and a significant blow to economic development in these regions.
Many of the attempted strategies to eliminate malaria in the past have planned to do so by eliminating mosquitoes entirely — but according to a recent press release, the Vector Genetics Laboratory (VGL) at UC Davis, in collaboration with a UC malaria initiative program that originally started at UC Irvine, and with the financial support of a $10.2 million grant from Open Philanthropy, is taking a different approach.
“Mosquitoes are a part of the ecosystem,” Greg Lanzaro, project principal investigator and director at VGL, said. “Our strategy does not eliminate mosquitoes. The mosquitoes will still be there, they’ll just be incapable of transmitting malaria. In every sense these mosquitoes are normal mosquitoes, except for the fact that they can’t transmit malaria.”
The idea is called a “population modification strategy,” Lanzaro said, explaining that groups at UC Irvine and Johns Hopkins University genetically engineered mosquitoes that are incapable of transmitting the malaria parasite.
“The way that malaria is transmitted is that the mosquito bites a person who has malaria and it picks up the parasite in the blood that it feeds on,” Lanzaro said. “Then the parasite develops in the mosquito so that when the mosquito bites the next person, they spread the parasite. Our mosquitoes have been engineered with a couple of genes that kill the parasite inside of the mosquito, so they’re not able to transmit.”
The plan is to eventually release these genetically modified mosquitoes into natural populations of mosquitoes, and allow the new genes to be passed down into the natural mosquito population. However, according to Lanzaro, having a malaria-proof mosquito isn’t enough to make this happen — they also need to develop a “gene drive.”
“The gene drive basically alters the way that our beneficial genes are inherited, so that they will very rapidly move through the natural population,” Lanzaro said.
According to Lanzaro, the necessary gene drive was developed at UC San Diego. Now that the science is ready, the UC Davis component of the project, which the grant was awarded for, has begun — to move the technology from the laboratory to the field.
“There’s basically two big components to that,” Lanzaro said. “There’s the biology, and there’s the social science aspect. For the biology, the idea is that we want to do trials, and see if this will work.”
Lanzaro said that the team spent a year looking at potential places to attempt a release before eventually selecting two small islands off the coast of Africa, São Tomé and Príncipe, for their initial trials. This decision was based partly on the convenience of the islands being “isolated contained systems.”
“Once we’ve selected the site, we have to study the ecology of the mosquitoes at the site, the genetics of the mosquitoes at that site, we have to look at the environment, we have to look at non-target organisms, all in preparation,” Lanzaro said. “All before we would ever think about doing a release.”
Ana Kormos, an engagement program manager at VGL, said that the decision to use these two islands as potential trial sites was made through direct involvement and discussion with the country’s government and communities.
“The model that we’re using puts our collaborators in the driver’s seat,” Kormos said. “That was really important to us […], that they are the ones who are actively participating in and making the decisions about what we’re doing, how we’re doing it, how we’re taking it to the next step. [We are] developing the strategy, developing the plan so we aren’t walking in with any preconceived ideas; we aren’t forcing an agenda. It’s really being directed by the end user.”
Kormos elaborated that apart from making the final decision about whether or not to release the transgenic mosquitoes, locals have also driven communication and informational efforts surrounding the project.
“We have hired local engagement professionals and community educators and local leaders to develop that strategy with their communities and then implement it,” Kormos said. “They are implementing a strategy that’s been designed and developed by them. They know their community, they understand what the education level looks like, how people prefer to receive information and how people feel the most comfortable sharing information back about what they think and feel about a particular subject.”
Lanzaro said that the team will spend the next three years assembling all the information they can on the genetics and biology of the mosquitoes, at which point they will present the data, potential benefits and potential risks to the authorities of São Tomé and Príncipe. The regulatory authorities will then make a decision about whether or not they’ll allow the release of the mosquitoes.
He explained another potential benefit of this project, aside from the hopeful elimination of malaria from Africa.
“In the old days people described malaria as a disease of poverty, but more contemporary analyses have shown that malaria actually creates poverty,” Lanzaro said. “And it does that by keeping such a high proportion of the population ill that they’re unable to show up for work, they’re unable to take care of their crops, they’re unable to attend schools. […] It also has an economic impact on tourism.”
Lanzaro concluded with another reason why this solution is structurally different from others proposed and implemented in the past.
“The thing that we really like about our program is that it’s sustainable and it’s cost-effective,” Lanzaro said. “Diseases that impose the heaviest burden on economically less developed countries is that you might get a country or an agency to put a bunch of money in to pay for nets, and insecticides, and it’s fine, it’s great, it works, but when the money dries up, malaria comes back. Our program is not only cost effective, they really only need to be released once and it’s done — the mosquitoes do the work themselves, really.”
Written by: Sonora Slater — science@theaggie.org
