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In last Friday’s newsletter, we told you about a foodborne parasitic outbreak that has sickened thousands of people across several states. Today we’re bringing you an update on a totally different ailment stalking Donald Trump’s America—one that was supposed to have been eliminated decades ago. Measles cases in the U.S. just set a depressing record, making 2026 the worst year for the disease since the Soviet Union collapsed. Here’s what’s behind the surge.

Wait, slow down. What does measles entail, again?

Measles is a highly contagious virus. Most cases are mild and amount to little more than a cough, fever, and runny nose. But severe illness can cause rashes, pneumonia, brain damage, or death, and younger children are at greater risk of hospitalization. Safe and effective vaccines have been widely available since the 1960s; by 2000, the U.S. declared measles eliminated here. But cases have skyrocketed in the past two years.

How bad is the current outbreak?

The Centers for Disease Control and Prevention counts 2,318 confirmed cases across the country so far this year, up from 2,289 in all of 2025—and we still have five months to go. That’s the highest number since 1991, and more cases in just the past two years than in every previous year since the........

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