The figures are stark. With nearly 36 million people worldwide suffering the mind-robbing disease Alzheimer’s, spending on their care accounts for one percent of global GDP. Health experts believe that number could double, triple or even quadruple in the next 40 years as the world’s population ages. It will likely become one of the biggest single public health issues worldwide.

That means we can expect more patients, and their families, who will fight for public resources to find a cure and help care for the ill. And the expectation that it will soon be possible to test people early for the disease, even before they show symptoms, will mean millions more citizens globally will become aware of how helpless we are right now in this fight.

This was one of the big themes during our discussion today at the Harvard School of Public Health, moderated by our own U.S. health correspondent Julie Steenhuysen. She spoke with Robert Blendon, health policy professor at HSPH, Adrian Ivinson, founding director of the Harvard Neurodiscovery Center, Matthew Baumgart, senior director of government affairs at the Alzheimer’s Association. See it here.

“There is going to be a sea change in public interest in investing in this,” Blendon said. “If you believe the darkness can be pushed away by medical research, you’re going to want your government do to something about this.”

Blendon presented a survey this week that showed Alzheimer’s is the disease people fear most, after cancer, and that a significant number would like to be tested early even if they don’t have symptoms. Many of those polled also believed that doctors had medicines at their disposal that could help treat the disease. Managing the disappointment when they realize the truth, as it affects them, will be a big part of how governments handle Alzheimer’s going forward.

We can expect even stickier issues when accurate diagnostics tests become available. When should insurance cover it? Should we know we have the disease at age 50, 40, 20? Our discussion partners today largely advocated early testing, particularly for people who are just starting to show symptoms or who are likely to be at risk, as that will help drug researchers in their search for a cure. But some, like Ivinson, saw little value for early testing of a broader population without good reason.

After the talk, Blendon and I discussed whether such testing could even become mandatory down the road for people in positions of high responsibility. It was possible, he said, if diagnostics became as simple as a blood test in the future. One that could be used to check military personnel. Or even candidates for U.S. president.

Below is an archive of our live coverage of today’s event: