I think I saw that story earlier. I believe the kid was unvaccinated (what a shock), traveled internationally, and brought measles back with them.
Why can't people be required to be vaccinated before traveling? I mean if vets can refuse to see a dog due to being behind on its shots, why can't brats and breeders be turned away at the airport for not having current vaccinations? In fairness, fake vaccine cards were a thing during the COVID-19 pandemic, so I'm sure it wouldn't be too hard to get a counterfeit vaccination card.
Measles was considered eradicated in the US years ago, but due to a combination of anti-vaccination and traveling abroad, it's been making a comeback. I'm sure if parents don't care enough about their kids' health to get them a shot, they don't care that measles can be fatal either. They might die from a preventable virus, but AT LEAST THEY WON'T HAVE AUTISM!!1

I'm sure the thought process was somewhere between "I don't care" and "if everyone else is vaccinated, why are they worried?" Same attitude during COVID. Vaccines help tremendously, but I think you do need boosters now and then. I'm not sure how often you need them for measles, but it might be good to find out if you need a measles booster considering the outbreaks that have been happening lately.