From the article:

The answer to how I became sick may lie in what’s called secondary vaccine failure, which happens when a vaccinated person’s immunity decreases over time until they are no longer protected. This can take place when an immune system doesn’t receive the “boost” it needs from encountering the virus.

“There is evidence to suggest that in the absence of these boosts, the immune response that is induced by the vaccine isn’t lasting as long,” said Janna Shapiro, a postdoctoral fellow at the Centre for Vaccine Preventable Diseases in Toronto. That means even those who were fully vaccinated as kids can lose their immunity.

This was me. I was at the doctor and he was having me get some bloodwork done. I asked him to check my measles immunity status, too, because I’d previously seen online of the possibility mentinoed above. My parents did have me immunized when I was a child, but I thought why not check? The results: I had no immunity.

It was free (to me, the patient) to get the shots. My doctor had to order them in. It’s two shots a month apart, and then another blood draw another month later to check. I’ll be honest, it was the second most painful vaccination I’ve ever had (the first was shingles), but totally worth it. Ask your doctor to check the next time you’re getting bloodwork done.