Bill Gates is promoting a plan to use wireless technology to register every newborn on the planet in a vaccine database.

In a keynote address to the mHealth Summit, which focuses on using mobile technology to improve health care, Gates said that improving survival rates among children under the age of 5 would benefit not just individual families, but societies and the planet as a whole. “The key thing, the most important fact that people should know and make sure other people know: As you save children under 5, that is the thing that reduces population growth,” he said. “That sounds paradoxical. The fact is that within a decade of improving health outcomes, parents decide to have less children.”

The number of children who die before their fifth birthday has already dropped from 20 million in 1960 to 8.5 million today, a statistic Gates attributes mostly to vaccination.

“About one-third [of that improvement] is by increasing income,” Gates said. “The majority has been through vaccines. Vaccines will be the key. If you could register every birth on a cell phone — get fingerprints, get a location — then you could [set up] systems to make sure the immunizations happen.”

Gates suggested using cell phones to record each birth and send the information, including biometric identifiers, to a central database. This database would then send reminders to parents’ phones when it was time to come in for vaccines or other treatments. He said a prime location to implement such programs would be northern Nigeria or northern India, where vaccination rates are less than 50 percent.

Acknowledging that registering every single birth has never been done before, Gates called for “1,000 new ideas” to “blossom” in order to make it happen.  Such ideas could conceivably involve using the GPS devices inside phones to physically track parents who do not bring their children in for vaccines.