Cuauhtemoc, Mexico —
It all started when a 9-year-old boy went with his parents to visit relatives in Seminole, Texas, early last year. After he returned home to Mexico, a red rash erupted on his skin. Within weeks, so many of his classmates fell ill that their school shut down.
Unbeknownst to the boy’s parents, measles had started to ricochet around Seminole during their visit.
The town would soon emerge as the epicenter of the biggest US outbreak in more than 30 years, one that would kill three Americans. But when the virus jumped the border to Mexico, a bigger tragedy was about to begin.
At least 40 Mexicans have died of…