New Delhi, June 12 -- ATLANTA - James Garrow has been planning for this moment for eighteen months. As Philadelphia's deputy health commissioner, he has run drills, built surveillance protocols, and spent hours on calls about what to do if measles shows up in a stadium packed with cheering fans from 48 countries. The tournament starts Thursday. He is still not sure he has everything he needs.

"Measles is probably our top worry," Garrow told the Center for Infectious Disease Research and Policy. "We've already put out communications to our regional healthcare providers about what to look for."

The 2026 FIFA World Cup opens Thursday across 16 cities in the United States, Canada, and Mexico, drawing an estimated 6.5 million fans into the k...