Melinda and I devote a lot of money and time to finding new and innovative ways to combat deadly diseases. But during a recent visit to Indonesia, I was asked to give something more—my blood.

Given the cause, I happily complied.

I got the request during a stop at Gadjah Mada University in Yogyakarta to check in on an amazing project to control the spread of dengue. Watch this video about my visit:

A mosquito-borne virus that causes serious illness and sometimes death, especially among children, dengue has spread dramatically in recent decades because of population growth and rapid urbanization in tropical and subtropical countries. About half of the world is now at risk of the disease. Last year, dengue cases were even discovered in Florida.

Researchers at the university are part of a global effort exploring whether a bacterium called WolbachiaWolbachia can be used to control dengue. occurs naturally in 70 percent of all insects, and it is harmless to humans. But it can block the transmission of dengue by mosquitoes. Unfortunately, the type of mosquito that carries dengue, Aedes aegyptiWolbachiaWolbachia, doesn’t naturally get , but one group of scientists discovered a way to infect them with it. Now, in partnership with other researchers around the world, they’re raising a colony of mosquitoes to be released in hopes that they will breed with wild mosquitoes and curb the spread of dengue. (The work in Indonesia is being funded by the Tahija Foundation of Indonesia.)

Working with local communities, researchers first released Wolbachia Wolbachia mosquitoes in Australia in 2011. In January, with the support of the government and residents, the Indonesian team began releasing mosquitoes in neighborhoods around Yogyakarta. During my visit, I had a chance to release dozens of the Wolbachia mosquitoes into the wild.

I also had an opportunity to speak with members of one neighborhood where the mosquitoes are now breeding. Several people told me about family members who became severely ill from dengue in recent years. One man had lost two family members to the disease. Now, they are optimistic that these mosquitoes will bring relief to the dengue burden in their city.

Many more of these amazing mosquitoes will need to be released into the wild in the months ahead before we can assess the impact of this project. That means the university’s research team will be busy breeding and raising thousands of Wolbachia mosquitoes. I have a lot of admiration for the members of the research team. Every week they take turns having their arms feasted on by several hundred very hungry female mosquitoes who need human blood to develop their eggs. There’s no risk of getting dengue from these lab-reared mosquitoes, but the bites itch just the same.

I learned that first hand when I agreed to offer a cage of mosquitoes a taste of my own blood. Within just a few minutes my arm swelled up with dozen of bites. It was a small price to pay for an amazing project that has the potential to turn the tide against a terrible disease.

To learn more about the effort to eliminate dengue, click here.